National Library of Energy BETA

Sample records for thin silicon solar

  1. Enabling Thin Silicon Solar Cell Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Enabling Thin Silicon Solar Cell Technology Enabling Thin Silicon Solar Cell Technology Print Friday, 21 June 2013 10:49 Generic silicon solar cells showing +45°, -45°, and dendritic crack patterns. The effort to shift U.S. energy reliance from fossil fuels to renewable sources has spurred companies to reduce the cost and increase the reliability of their solar photovoltaics (SPVs). The use of thinner silicon in SPV technologies is being widely adopted because it significantly reduces costs;

  2. Flexible Thin-Film Silicon Solar Cells

    SciTech Connect (OSTI)

    Vijh, Aarohi; Cao, Simon; Mohring, Brad

    2014-01-11

    High fuel costs, environmental concerns and issues of national energy security have brought increasing attention to a distributed generation program for electricity based on solar technology. Rooftop photovoltaic (PV) systems provide distributed generation since the power is consumed at the point of production, thus eliminating the need for costly additional transmission lines. However, most current photovoltaic modules are heavy and require a significant amount of labor and accessory hardware such as mounting frames for installation on rooftops. This makes rooftop systems impractical or cost prohibitive in many instances. Under this project, Xunlight has advanced its manufacturing process for the production of lightweight, flexible thin-film silicon based photovoltaic modules, and has enhanced the reliability and performance of Xunlights products. These modules are easily unrolled and adhered directly to standard commercial roofs without mounting structures or integrated directly into roofing membrane materials for the lowest possible installation costs on the market. Importantly, Xunlight has now established strategic alliances with roofing material manufacturers and other OEMs for the development of building integrated photovoltaic roofing and other PV-enabled products, and has deployed its products in a number of commercial installations with these business partners.

  3. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, T.F.

    1995-03-28

    A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1{times}10{sup {minus}3} ohm-cm. 4 figures.

  4. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, Theodore F. (Evergreen, CO)

    1995-01-01

    A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1.times.10.sup.-3 ohm-cm.

  5. Enabling Thin Silicon Solar Cell Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    joined what he calls "the race of the SPV panel." He hopes to help create an SVP panel (a connected assembly of solar cells that turns sunlight into usable energy) that...

  6. High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers

    SciTech Connect (OSTI)

    Antoniadis, H.

    2011-03-01

    Reported are the development and demonstration of a 17% efficient 25mm x 25mm crystalline Silicon solar cell and a 16% efficient 125mm x 125mm crystalline Silicon solar cell, both produced by Ink-jet printing Silicon Ink on a thin crystalline Silicon wafer. To achieve these objectives, processing approaches were developed to print the Silicon Ink in a predetermined pattern to form a high efficiency selective emitter, remove the solvents in the Silicon Ink and fuse the deposited particle Silicon films. Additionally, standard solar cell manufacturing equipment with slightly modified processes were used to complete the fabrication of the Silicon Ink high efficiency solar cells. Also reported are the development and demonstration of a 18.5% efficient 125mm x 125mm monocrystalline Silicon cell, and a 17% efficient 125mm x 125mm multicrystalline Silicon cell, by utilizing high throughput Ink-jet and screen printing technologies. To achieve these objectives, Innovalight developed new high throughput processing tools to print and fuse both p and n type particle Silicon Inks in a predetermined pat-tern applied either on the front or the back of the cell. Additionally, a customized Ink-jet and screen printing systems, coupled with customized substrate handling solution, customized printing algorithms, and a customized ink drying process, in combination with a purchased turn-key line, were used to complete the high efficiency solar cells. This development work delivered a process capable of high volume producing 18.5% efficient crystalline Silicon solar cells and enabled the Innovalight to commercialize its technology by the summer of 2010.

  7. Thin silicon foils produced by epoxy-induced spalling of silicon for high efficiency solar cells

    SciTech Connect (OSTI)

    Martini, R., E-mail: roberto.martini@imec.be [Department of Electrical Engineering, KU Leuven, Kasteelpark 10, 3001 Leuven (Belgium); imec, Kapeldreef 75, 3001 Leuven (Belgium); Kepa, J.; Stesmans, A. [Department of Physics, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven (Belgium); Debucquoy, M.; Depauw, V.; Gonzalez, M.; Gordon, I. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Poortmans, J. [Department of Electrical Engineering, KU Leuven, Kasteelpark 10, 3001 Leuven (Belgium); imec, Kapeldreef 75, 3001 Leuven (Belgium); Universiteit Hasselt, Martelarenlaan 42, B-3500 Hasselt (Belgium)

    2014-10-27

    We report on the drastic improvement of the quality of thin silicon foils produced by epoxy-induced spalling. In the past, researchers have proposed to fabricate silicon foils by spalling silicon substrates with different stress-inducing materials to manufacture thin silicon solar cells. However, the reported values of effective minority carrier lifetime of the fabricated foils remained always limited to ?100??s or below. In this work, we investigate epoxy-induced exfoliated foils by electron spin resonance to analyze the limiting factors of the minority carrier lifetime. These measurements highlight the presence of disordered dangling bonds and dislocation-like defects generated by the exfoliation process. A solution to remove these defects compatible with the process flow to fabricate solar cells is proposed. After etching off less than 1??m of material, the lifetime of the foil increases by more than a factor of 4.5, reaching a value of 461??s. This corresponds to a lower limit of the diffusion length of more than 7 times the foil thickness. Regions with different lifetime correlate well with the roughness of the crack surface which suggests that the lifetime is now limited by the quality of the passivation of rough surfaces. The reported values of the minority carrier lifetime show a potential for high efficiency (>22%) thin silicon solar cells.

  8. Record Makes Thin-Film Solar Cell Competitive with Silicon Efficiency -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    News Releases | NREL Record Makes Thin-Film Solar Cell Competitive with Silicon Efficiency March 24, 2008 Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory have moved closer to creating a thin-film solar cell that can compete with the efficiency of the more common silicon-based solar cell. The copper indium gallium diselenide (CIGS) thin-film solar cell recently reached 19.9 percent efficiency, setting a new world record for this type of cell.

  9. Thin Single Crystal Silicon Solar Cells on Ceramic Substrates: November 2009 - November 2010

    SciTech Connect (OSTI)

    Kumar, A.; Ravi, K. V.

    2011-06-01

    In this program we have been developing a technology for fabricating thin (< 50 micrometres) single crystal silicon wafers on foreign substrates. We reverse the conventional approach of depositing or forming silicon on foreign substrates by depositing or forming thick (200 to 400 micrometres) ceramic materials on high quality single crystal silicon films ~ 50 micrometres thick. Our key innovation is the fabrication of thin, refractory, and self-adhering 'handling layers or substrates' on thin epitaxial silicon films in-situ, from powder precursors obtained from low cost raw materials. This 'handling layer' has sufficient strength for device and module processing and fabrication. Successful production of full sized (125 mm X 125 mm) silicon on ceramic wafers with 50 micrometre thick single crystal silicon has been achieved and device process flow developed for solar cell fabrication. Impurity transfer from the ceramic to the silicon during the elevated temperature consolidation process has resulted in very low minority carrier lifetimes and resulting low cell efficiencies. Detailed analysis of minority carrier lifetime, metals analysis and device characterization have been done. A full sized solar cell efficiency of 8% has been demonstrated.

  10. Light Trapping for Thin Silicon Solar Cells by Femtosecond Laser Texturing: Preprint

    SciTech Connect (OSTI)

    Lee, B. G.; Lin, Y. T.; Sher, M. J.; Mazur, E.; Branz, H. M.

    2012-06-01

    Femtosecond laser texturing is used to create nano- to micron-scale surface roughness that strongly enhances light-trapping in thin crystalline silicon solar cells. Light trapping is crucial for thin solar cells where a single light-pass through the absorber is insufficient to capture the weakly absorbed red and near-infrared photons, especially with an indirect-gap semiconductor absorber layer such as crystalline Si which is less than 20 um thick. We achieve enhancement of the optical absorption from light-trapping that approaches the Yablonovitch limit.

  11. Optimization of the antireflection coating of thin epitaxial crystalline silicon solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Selj, Josefine K.; Young, David; Grover, Sachit

    2015-08-28

    In this study we use an effective weighting function to include the internal quantum efficiency (IQE) and the effective thickness, Te, of the active cell layer in the optical modeling of the antireflection coating (ARC) of very thin crystalline silicon solar cells. The spectrum transmitted through the ARC is hence optimized for efficient use in the given cell structure and the solar cell performance can be improved. For a 2-μm thick crystalline silicon heterojunction solar cell the optimal thickness of the Indium Tin Oxide (ITO) ARC is reduced by ~8 nm when IQE data and effective thickness are taken intomore » account compared to the standard ARC optimization, using the AM1.5 spectrum only. The reduced ARC thickness will shift the reflectance minima towards shorter wavelengths and hence better match the absorption of very thin cells, where the short wavelength range of the spectrum is relatively more important than the long, weakly absorbed wavelengths. For this cell, we find that the optimal thickness of the ITO starts at 63 nm for very thin (1 μm) active Si layer and then increase with increasing Te until it saturates at 71 nm for Te > 30 μm.« less

  12. Optimization of the antireflection coating of thin epitaxial crystalline silicon solar cells

    SciTech Connect (OSTI)

    Selj, Josefine K.; Young, David; Grover, Sachit

    2015-08-28

    In this study we use an effective weighting function to include the internal quantum efficiency (IQE) and the effective thickness, Te, of the active cell layer in the optical modeling of the antireflection coating (ARC) of very thin crystalline silicon solar cells. The spectrum transmitted through the ARC is hence optimized for efficient use in the given cell structure and the solar cell performance can be improved. For a 2-μm thick crystalline silicon heterojunction solar cell the optimal thickness of the Indium Tin Oxide (ITO) ARC is reduced by ~8 nm when IQE data and effective thickness are taken into account compared to the standard ARC optimization, using the AM1.5 spectrum only. The reduced ARC thickness will shift the reflectance minima towards shorter wavelengths and hence better match the absorption of very thin cells, where the short wavelength range of the spectrum is relatively more important than the long, weakly absorbed wavelengths. For this cell, we find that the optimal thickness of the ITO starts at 63 nm for very thin (1 μm) active Si layer and then increase with increasing Te until it saturates at 71 nm for Te > 30 μm.

  13. Thin film polycrystalline silicon: Promise and problems in displays and solar cells

    SciTech Connect (OSTI)

    Fonash, S.J.

    1995-08-01

    Thin film polycrystalline Si (poly-Si) with its carrier mobilities, potentially good stability, low intragrain defect density, compatibility with silicon processing, and ease of doping activation is an interesting material for {open_quotes}macroelectronics{close_quotes} applications such as TFTs for displays and solar cells. The poly-Si films needed for these applications can be ultra-thin-in the 500{Angstrom} to 1000{Angstrom} thickness range for flat panel display TFTs and in the 4{mu}m to 10{mu}m thickness range for solar cells. Because the films needed for these microelectronics applications can be so thin, an effective approach to producing the films is that of crystallizing a-Si precursor material. Unlike cast materials, poly-Si films made this way can be produced using low temperature processing. Unlike deposited poly-Si films, these crystallized poly-Si films can have grain widths that are much larger than the film thickness and almost atomically smooth surfaces. This thin film poly-Si crystallized from a-Si precursor films, and its promise and problems for TFTs and solar cells, is the focus of this discussion.

  14. Development of Commercial Technology for Thin Film Silicon Solar Cells on Glass: Cooperative Research and Development Final Report, CRADA Number CRD-07-209

    SciTech Connect (OSTI)

    Sopori, B.

    2013-03-01

    NREL has conducted basic research relating to high efficiency, low cost, thin film silicon solar cell design and the method of making solar cells. Two patents have been issued to NREL in the above field. In addition, specific process and metrology tools have been developed by NREL. Applied Optical Sciences Corp. (AOS) has expertise in the manufacture of solar cells and has developed its own unique concentrator technology. AOS wants to complement its solar cell expertise and its concentrator technology by manufacturing flat panel thin film silicon solar cell panels. AOS wants to take NREL's research to the next level, using it to develop commercially viable flat pane, thin film silicon solar cell panels. Such a development in equipment, process, and metrology will likely produce the lowest cost solar cell technology for both commercial and residential use. NREL's fundamental research capability and AOS's technology and industrial background are complementary to achieve this product development.

  15. Thinner Film Silicon Solar Cells - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    thin film silicon solar cells with a potential increase in photon energy conversion of up to 20%, a significant improvement over conventional thin film photovoltaic technologies. ...

  16. Electrochemical thinning of silicon

    DOE Patents [OSTI]

    Medernach, J.W.

    1994-01-11

    Porous semiconducting material, e.g. silicon, is formed by electrochemical treatment of a specimen in hydrofluoric acid, using the specimen as anode. Before the treatment, the specimen can be masked. The porous material is then etched with a caustic solution or is oxidized, depending of the kind of structure desired, e.g. a thinned specimen, a specimen, a patterned thinned specimen, a specimen with insulated electrical conduits, and so on. Thinned silicon specimen can be subjected to tests, such as measurement of interstitial oxygen by Fourier transform infra-red spectroscopy (FTIR). 14 figures.

  17. Electrochemical thinning of silicon

    DOE Patents [OSTI]

    Medernach, John W.

    1994-01-01

    Porous semiconducting material, e.g. silicon, is formed by electrochemical treatment of a specimen in hydrofluoric acid, using the specimen as anode. Before the treatment, the specimen can be masked. The porous material is then etched with a caustic solution or is oxidized, depending of the kind of structure desired, e.g. a thinned specimen, a specimen, a patterned thinned specimen, a specimen with insulated electrical conduits, and so on. Thinned silicon specimen can be subjected to tests, such as measurement of interstitial oxygen by Fourier transform infra-red spectroscopy (FTIR).

  18. Technology Development for High-Efficiency Solar Cells and Modules Using Thin (<80 um) Single-Crystal Silicon Wafers Produced by Epitaxy: June 11, 2011 - April 30, 2013

    SciTech Connect (OSTI)

    Ravi, T. S.

    2013-05-01

    Final technical progress report of Crystal Solar subcontract NEU-31-40054-01. The objective of this 18-month program was to demonstrate the viability of high-efficiency thin (less than 80 um) monocrystalline silicon (Si) solar cells and modules with a low-cost epitaxial growth process.

  19. Towards high efficiency thin-film crystalline silicon solar cells: The roles of light trapping and non-radiative recombinations

    SciTech Connect (OSTI)

    Bozzola, A. Kowalczewski, P.; Andreani, L. C.

    2014-03-07

    Thin-film solar cells based on silicon have emerged as an alternative to standard thick wafers technology, but they are less efficient, because of incomplete absorption of sunlight, and non-radiative recombinations. In this paper, we focus on the case of crystalline silicon (c-Si) devices, and we present a full analytic electro-optical model for p-n junction solar cells with Lambertian light trapping. This model is validated against numerical solutions of the drift-diffusion equations. We use this model to investigate the interplay between light trapping, and bulk and surface recombination. Special attention is paid to surface recombination processes, which become more important in thinner devices. These effects are further amplified due to the textures required for light trapping, which lead to increased surface area. We show that c-Si solar cells with thickness of a few microns can overcome 20% efficiency and outperform bulk ones when light trapping is implemented. The optimal device thickness in presence of light trapping, bulk and surface recombination, is quantified to be in the range of 1080??m, depending on the bulk quality. These results hold, provided the effective surface recombination is kept below a critical level of the order of 100?cm/s. We discuss the possibility of meeting this requirement, in the context of state-of-the-art techniques for light trapping and surface passivation. We show that our predictions are within the capability of present day silicon technologies.

  20. PEDOT:PSS emitters on multicrystalline silicon thin-film absorbers for hybrid solar cells

    SciTech Connect (OSTI)

    Junghanns, Marcus; Plentz, Jonathan Andr, Gudrun; Gawlik, Annett; Hger, Ingmar; Falk, Fritz

    2015-02-23

    We fabricated an efficient hybrid solar cell by spin coating poly(3,4-ethylene-dioxythiophene):polystyrenesulfonate (PEDOT:PSS) on planar multicrystalline Si (mc-Si) thin films. The only 5??m thin Si absorber layers were prepared by diode laser crystallization of amorphous Si deposited by electron beam evaporation on glass. On these absorber layers, we studied the effect of SiO{sub x} and Al{sub 2}O{sub 3} terminated Si surfaces. The short circuit density and power conversion efficiency (PCE) of the mc-Si/Al{sub 2}O{sub 3}/PEDOT:PSS solar cell increase from 20.6 to 25.4?mA/cm{sup 2} and from 7.3% to 10.3%, respectively, as compared to the mc-Si/SiO{sub x}/PEDOT:PSS cell. Al{sub 2}O{sub 3} lowers the interface recombination and improves the adhesion of the polymer film on the hydrophobic mc-Si thin film. Open circuit voltages up to 604?mV were reached. This study demonstrates the highest PCE so far of a hybrid solar cell with a planar thin film Si absorber.

  1. Development of Thin Film Silicon Solar Cell Using Inkjet Printed Silicon and Other Inkjet Processes: Cooperative Research and Development Final Report, CRADA Number CRD-07-260

    SciTech Connect (OSTI)

    Sopori, B.

    2012-04-01

    The cost of silicon photovoltaics (Si-PV) can be greatly lowered by developing thin-film crystalline Si solar cells on glass or an equally lower cost substrate. Typically, Si film is deposited by thermal evaporation, plasma enhanced chemical vapor deposition, and sputtering. NREL and Silexos have worked under a CRADA to develop technology to make very low cost solar cells using liquid organic precursors. Typically, cyclopentasilane (CPS) is deposited on a glass substrate and then converted into an a-Si film by UV polymerization followed by low-temperature optical process that crystallizes the amorphous layer. This technique promises to be a very low cost approach for making a Si film.

  2. Picosecond and nanosecond laser annealing and simulation of amorphous silicon thin films for solar cell applications

    SciTech Connect (OSTI)

    Theodorakos, I.; Zergioti, I.; Tsoukalas, D.; Raptis, Y. S.; Vamvakas, V.

    2014-01-28

    In this work, a picosecond diode pumped solid state laser and a nanosecond Nd:YAG laser have been used for the annealing and the partial nano-crystallization of an amorphous silicon layer. These experiments were conducted as an alternative/complementary to plasma-enhanced chemical vapor deposition method for fabrication of micromorph tandem solar cell. The laser experimental work was combined with simulations of the annealing process, in terms of temperature distribution evolution, in order to predetermine the optimum annealing conditions. The annealed material was studied, as a function of several annealing parameters (wavelength, pulse duration, fluence), as far as it concerns its structural properties, by X-ray diffraction, SEM, and micro-Raman techniques.

  3. Large-Scale PV Module Manufacturing Using Ultra-Thin Polycrystalline Silicon Solar Cells: Final Subcontract Report, 1 April 2002--28 February 2006

    SciTech Connect (OSTI)

    Wohlgemuth, J.; Narayanan, M.

    2006-07-01

    The major objectives of this program were to continue advances of BP Solar polycrystalline silicon manufacturing technology. The Program included work in the following areas. (1) Efforts in the casting area to increase ingot size, improve ingot material quality, and improve handling of silicon feedstock as it is loaded into the casting stations. (2) Developing wire saws to slice 100-..mu..m-thick silicon wafers on 290-..mu..m-centers. (3) Developing equipment for demounting and subsequent handling of very thin silicon wafers. (4) Developing cell processes using 100-..mu..m-thick silicon wafers that produce encapsulated cells with efficiencies of at least 15.4% at an overall yield exceeding 95%. (5) Expanding existing in-line manufacturing data reporting systems to provide active process control. (6) Establishing a 50-MW (annual nominal capacity) green-field Mega-plant factory model template based on this new thin polycrystalline silicon technology. (7) Facilitating an increase in the silicon feedstock industry's production capacity for lower-cost solar-grade silicon feedstock..

  4. Optimal design of one-dimensional photonic crystal back reflectors for thin-film silicon solar cells

    SciTech Connect (OSTI)

    Chen, Peizhuan; Hou, Guofu Zhang, Jianjun Zhang, Xiaodan; Zhao, Ying

    2014-08-14

    For thin-film silicon solar cells (TFSC), a one-dimensional photonic crystal (1D PC) is a good back reflector (BR) because it increases the total internal reflection at the back surface. We used the plane-wave expansion method and the finite difference time domain (FDTD) algorithm to simulate and analyze the photonic bandgap (PBG), the reflection and the absorption properties of a 1D PC and to further explore the optimal 1D PC design for use in hydrogenated amorphous silicon (a-Si:H) solar cells. With identified refractive index contrast and period thickness, we found that the PBG and the reflection of a 1D PC are strongly influenced by the contrast in bilayer thickness. Additionally, light coupled to the top three periods of the 1D PC and was absorbed if one of the bilayers was absorptive. By decreasing the thickness contrast of the absorptive layer relative to the non-absorptive layer, an average reflectivity of 96.7% was achieved for a 1D PC alternatively stacked with a-Si:H and SiO{sub 2} in five periods. This reflectivity was superior to a distributed Bragg reflector (DBR) structure with 93.5% and an Ag film with 93.4%. n-i-p a-Si:H solar cells with an optimal 1D PC-based BR offer a higher short-circuit current density than those with a DBR-based BR or an AZO/Ag-based BR. These results provide new design rules for photonic structures in TFSC.

  5. Electrical properties and surface morphology of electron beam evaporated p-type silicon thin films on polyethylene terephthalate for solar cells applications

    SciTech Connect (OSTI)

    Ang, P. C.; Ibrahim, K.; Pakhuruddin, M. Z.

    2015-04-24

    One way to realize low-cost thin film silicon (Si) solar cells fabrication is by depositing the films with high-deposition rate and manufacturing-compatible electron beam (e-beam) evaporation onto inexpensive foreign substrates such as glass or plastic. Most of the ongoing research is reported on e-beam evaporation of Si films on glass substrates to make polycrystalline solar cells but works combining both e-beam evaporation and plastic substrates are still scarce in the literature. This paper studies electrical properties and surface morphology of 1 m electron beam evaporated Al-doped p-type silicon thin films on textured polyethylene terephthalate (PET) substrate for application as an absorber layer in solar cells. In this work, Si thin films with different doping concentrations (including an undoped reference) are prepared by e-beam evaporation. Energy dispersion X-ray (EDX) showed that the Si films are uniformly doped by Al dopant atoms. With increased Al/Si ratio, doping concentration increased while both resistivity and carrier mobility of the films showed opposite relationships. Root mean square (RMS) surface roughness increased. Overall, the Al-doped Si film with Al/Si ratio of 2% (doping concentration = 1.5710{sup 16} atoms/cm{sup 3}) has been found to provide the optimum properties of a p-type absorber layer for fabrication of thin film Si solar cells on PET substrate.

  6. Thin Silicon Solar Cells: A Path to 35% Shockley-Queisser Limits

    SciTech Connect (OSTI)

    Ding, Laura; Boccard, Mathieu; Williams, Joshua; Jeffries, April; Gangam, Srikanth; Ghosh, Kunal; Honsberg, Christiana; Bowden, Stuart; Holman, Zachary; Atwater, Harry; Buonassisi, Tonio; Bremner, Stephen; Green, Martin; Balif, Christoph; Bertoni, Mariana

    2014-06-08

    Crystalline silicon technology is expected to remain the leading photovoltaic industry workhorse for decades. We present here the objectives and workplan of a recently launched project funded by the U.S. Department of Energy through the Foundational Program to Advance Cell Efficiency II (FPACE II), which aims at leading crystalline silicon to an efficiency breakthrough. The project will tackle fundamental approach of materials design, defect engineering, device simulations and materials growth and characterization. Among the main novelties, the implementation of carrier selective contacts made of wide bandgap material or stack of materials is investigated for improved passivation, carrier extraction and carrier transport. Based on an initial selection of candidate materials, preliminary experiments are conducted to verify the suitability of their critical parameters as well as preservation of the silicon substrate surface and bulk properties. The target materials include III-V and metal-oxide materials.

  7. Value Proposition for High Lifetime (p-type) and Thin Silicon Materials in Solar PV Applications: Preprint

    SciTech Connect (OSTI)

    Goodrich, A.; Woodhouse, M.; Hacke, P.

    2012-06-01

    Most silicon PV road maps forecast a continued reduction in wafer thickness, despite rapid declines in the primary incentive for doing so -- polysilicon feedstock price. Another common feature of most silicon-technology forecasts is the quest for ever-higher device performance at the lowest possible costs. The authors present data from device-performance and manufacturing- and system-installation cost models to quantitatively establish the incentives for manufacturers to pursue advanced (thin) wafer and (high efficiency) cell technologies, in an age of reduced feedstock prices. This analysis exhaustively considers the value proposition for high lifetime (p-type) silicon materials across the entire c-Si PV supply chain.

  8. Performance enhancement of thin film silicon solar cells based on distributed Bragg reflector and diffraction grating

    SciTech Connect (OSTI)

    Dubey, R. S.; Saravanan, S.; Kalainathan, S.

    2014-12-15

    The influence of various designing parameters were investigated and explored for high performance solar cells. Single layer grating based solar cell of 50 ?m thickness gives maximum efficiency up to 24 % whereas same efficiency is achieved with the use of three bilayers grating based solar cell of 30 ?m thickness. Remarkably, bilayer grating based solar cell design not only gives broadband absorption but also enhancement in efficiency with reduced cell thickness requirement. This absorption enhancement is attributed to the high reflection and diffraction from DBR and grating respectively. The obtained short-circuit current were 29.6, 32.9, 34.6 and 36.05 mA/cm{sup 2} of 5, 10, 20 and 30 ?m cell thicknesses respectively. These presented designing efforts would be helpful to design and realize new generation of solar cells.

  9. ThinSilicon | Open Energy Information

    Open Energy Info (EERE)

    ThinSilicon Place: California Product: US-based developer of thin-film PV module manufacturing technology. References: ThinSilicon1 This article is a stub. You can help OpenEI...

  10. High efficiency, low cost, thin film silicon solar cell design and method for making

    DOE Patents [OSTI]

    Sopori, Bhushan L.

    2001-01-01

    A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.

  11. High efficiency low cost thin film silicon solar cell design and method for making

    DOE Patents [OSTI]

    Sopori, Bhushan L.

    1999-01-01

    A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.

  12. High efficiency low cost thin film silicon solar cell design and method for making

    DOE Patents [OSTI]

    Sopori, B.L.

    1999-04-27

    A semiconductor device is described having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer. 9 figs.

  13. Research on high-efficiency, multiple-gap, multijunction, amorphous-silicon-based alloy thin-film solar cells

    SciTech Connect (OSTI)

    Guha, S. )

    1989-06-01

    This report presents results of research on advancing our understanding of amorphous-silicon-based alloys and their use in small-area multijunction solar cells. The principal objectives of the program are to develop a broad scientific base for the chemical, structural, optical, and electronic properties of amorphous-silicon-based alloys; to determine the optimum properties of these alloy materials as they relate to high-efficiency cells; to determine the optimum device configuration for multijunction cells; and to demonstrate proof-of-concept, multijunction, a-Si-alloy-based solar cells with 18% efficiency under standard AM1.5 global insolation conditions and with an area of at least 1 cm{sup 2}. A major focus of the work done during this reporting period was the optimization of a novel, multiple-graded structure that enhances cell efficiency through band-gap profiling. The principles of the operation of devices incorporating such a structure, computer simulations of those, and experimental results for both single- and multijunction cells prepared by using the novel structure are discussed in detail. 14 refs., 35 figs., 7 tabs.

  14. Silicon-film{trademark} on ceramic solar cells. Final report

    SciTech Connect (OSTI)

    Hall, R.B.; Bacon, C.; DiReda, V.; Ford, D.H.; Ingram, A.E.; Lampo, S.M.; Rand, J.A.; Ruffins, T.R.; Barnett, A.M.

    1993-02-01

    The Silicon-Film{trademark} design achieves high performance through the use of a thin silicon layer. Optimally designed thin crystalline solar cells (<50 microns thick) have performance advantages over conventional thick devices. The enhancement in performance requires the incorporation of back-surface passivation and light trapping. The high-performance Silicon-Film{trademark} design employs a metallurgical barrier between the low-cost substrate and the thin silicon layer. The properties of the metallurgical barrier must be engineered to implement specific device requirements, such as high back-surface reflectivity. Recent advances in process development are described here.

  15. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA)

    1980-01-01

    An amorphous silicon solar cell incorporates a region of intrinsic hydrogenated amorphous silicon fabricated by a glow discharge wherein said intrinsic region is compensated by P-type dopants in an amount sufficient to reduce the space charge density of said region under illumination to about zero.

  16. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Devaud, Genevieve (629 S. Humphrey Ave., Oak Park, IL 60304)

    1983-01-01

    An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon over said substrate and having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the electrically conductive substrate and an electrode for electrically contacting the second major surface. The intrinsic hydrogenated amorphous silicon region is deposited in a glow discharge with an atmosphere which includes not less than about 0.02 atom percent mono-atomic boron. An improved N.I.P. solar cell is disclosed using a BF.sub.3 doped intrinsic layer.

  17. Effect of Dual-Function Nano-Structured Silicon Oxide Thin Film on Multi-Junction Solar Cells

    SciTech Connect (OSTI)

    Yan, B.; Sivec, L.; Yue, G.; Jiang, C. S.; Yang, J.; Guha, S.

    2011-01-01

    We present our recent study of using nano-structured hydrogenated silicon oxide films (nc-SiO{sub x}:H) as a dual-function layer in multi-junction solar cells. The nc-SiO{sub x}:H films were deposited using very high frequency glow discharge of a SiH{sub 4} (or Si{sub 2}H{sub 6}), CO{sub 2}, PH{sub 3}, and H{sub 2} gas mixture. By optimizing deposition parameters, we obtained 'dual function' nc-SiO{sub x}:H material characterized by a conductivity suitable for use as an n layer and optical properties suitable for use as an inter-reflection layer. We tested the nc-SiO{sub x}:H by replacing the normal n-type material in the tunnel junction of a multi-junction structure. The advantage of the dual-function nc-SiO{sub x}:H layer is twofold; one is to simplify the cell structure, and the other is to reduce any optical loss associated with the inter-reflection layer. Quantum efficiency measurements show the gain in top cell current is equal to or greater than the loss in bottom cell current for a-Si:H/nc-Si:H structures. In addition, a thinner a-Si:H top cell with the nc-SiO{sub x}:H n layer improves the top-cell stability, thereby providing higher stabilized solar cell efficiency. We also used the dual-function layer between the middle and the bottom cells in a-Si:H/a-SiGe:H/nc-Si:H triple-junction structures. The gain in the middle cell current is {approx}1.0 mA/cm{sup 2}, leading to an initial active-area efficiency of 14.8%.

  18. Silicon Valley Solar Inc SV Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc SV Solar Jump to: navigation, search Name: Silicon Valley Solar Inc (SV Solar) Place: Santa Clara, California Zip: 95051 Sector: Solar Product: A US-based manufacturer of...

  19. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y. Simon (Golden, CO); Landry, Marc D. (Lafayette, CO); Pitts, John R. (Lakewood, CO)

    1997-01-01

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystallline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation.

  20. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y.S.; Landry, M.D.; Pitts, J.R.

    1997-05-06

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystalline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation. 2 figs.

  1. Thin Film Solar Technologies | Open Energy Information

    Open Energy Info (EERE)

    help OpenEI by expanding it. Thin Film Solar Technologies is a company located in South Africa . References "Thin Film Solar Technologies" Retrieved from "http:...

  2. Solar Thin Power | Open Energy Information

    Open Energy Info (EERE)

    Power Jump to: navigation, search Name: Solar Thin Power Place: New York Sector: Solar Product: Solar Thin Power was formed to seek out solar projects in North America, Asia and...

  3. Amorphous silicon passivated contacts for diffused junction silicon solar cells

    SciTech Connect (OSTI)

    Bullock, J. Yan, D.; Wan, Y.; Cuevas, A.; Demaurex, B.; Hessler-Wyser, A.; De Wolf, S.

    2014-04-28

    Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue, we insert thin intrinsic hydrogenated amorphous silicon [a-Si:H(i)] passivating films between the dopant-diffused silicon surface and aluminum contacts. We find that with increasing a-Si:H(i) interlayer thickness (from 0 to 16?nm) the recombination loss at metal-contacted phosphorus (n{sup +}) and boron (p{sup +}) diffused surfaces decreases by factors of ?25 and ?10, respectively. Conversely, the contact resistivity increases in both cases before saturating to still acceptable values of ? 50 m? cm{sup 2} for n{sup +} and ?100 m? cm{sup 2} for p{sup +} surfaces. Carrier transport towards the contacts likely occurs by a combination of carrier tunneling and aluminum spiking through the a-Si:H(i) layer, as supported by scanning transmission electron microscopyenergy dispersive x-ray maps. We explain the superior contact selectivity obtained on n{sup +} surfaces by more favorable band offsets and capture cross section ratios of recombination centers at the c-Si/a-Si:H(i) interface.

  4. Engineering Metal Impurities in Multicrystalline Silicon Solar...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of multicrystalline silicon solar cells led to the concept of defect engineering by ... systems decreased from the current price of approximately 16,000-25,000. One way ...

  5. The silicon/zinc oxide interface in amorphous silicon-based thin-film solar cells: Understanding an empirically optimized contact

    SciTech Connect (OSTI)

    Gerlach, D.; Wilks, R. G.; Wimmer, M.; Felix, R.; Gorgoi, M.; Lips, K.; Rech, B.; Wippler, D.; Mueck, A.; Meier, M.; Huepkes, J.; Lozac'h, M.; Ueda, S.; Sumiya, M.; Yoshikawa, H.; Kobayashi, K.; Baer, M.

    2013-07-08

    The electronic structure of the interface between the boron-doped oxygenated amorphous silicon 'window layer' (a-SiO{sub x}:H(B)) and aluminum-doped zinc oxide (ZnO:Al) was investigated using hard x-ray photoelectron spectroscopy and compared to that of the boron-doped microcrystalline silicon ({mu}c-Si:H(B))/ZnO:Al interface. The corresponding valence band offsets have been determined to be (-2.87 {+-} 0.27) eV and (-3.37 {+-} 0.27) eV, respectively. A lower tunnel junction barrier height at the {mu}c-Si:H(B)/ZnO:Al interface compared to that at the a-SiO{sub x}:H(B)/ZnO:Al interface is found and linked to the higher device performances in cells where a {mu}c-Si:H(B) buffer between the a-Si:H p-i-n absorber stack and the ZnO:Al contact is employed.

  6. Overview and Challenges of Thin Film Solar Electric Technologies

    SciTech Connect (OSTI)

    Ullal, H. S.

    2008-12-01

    In this paper, we report on the significant progress made worldwide by thin-film solar cells, namely, amorphous silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium diselenide (CIGS). Thin-film photovoltaic (PV) technology status is also discussed in detail. In addition, R&D and technology challenges in all three areas are elucidated. The worldwide estimated projection for thin-film PV technology production capacity announcements are estimated at more than 5000 MW by 2010.

  7. Spectroscopic ellipsometry characterization of thin-film silicon nitride

    SciTech Connect (OSTI)

    Jellison, G.E. Jr.; Modine, F.A.; Doshi, P.; Rohatgi, A.

    1997-05-01

    We have measured and analyzed the optical characteristics of a series of silicon nitride thin films prepared by plasma-enhanced chemical vapor deposition on silicon substrates for photovoltaic applications. Spectroscopic ellipsometry measurements were made by using a two-channel spectroscopic polarization modulator ellipsometer that measures N, S, and C data simultaneously. The data were fit to a model consisting of air / roughness / SiN / crystalline silicon. The roughness was modeled using the Bruggeman effective medium approximation, assuming 50% SiN, 50% voids. The optical functions of the SiN film were parameterized using a model by Jellison and Modine. All the {Chi}{sup 2} are near 1, demonstrating that this model works extremely well for all SiN films. The measured dielectric functions were used to make optimized SiN antireflection coatings for crystalline silicon solar cells.

  8. Tandem junction amorphous silicon solar cells

    DOE Patents [OSTI]

    Hanak, Joseph J. (Lawrenceville, NJ)

    1981-01-01

    An amorphous silicon solar cell has an active body with two or a series of layers of hydrogenated amorphous silicon arranged in a tandem stacked configuration with one optical path and electrically interconnected by a tunnel junction. The layers of hydrogenated amorphous silicon arranged in tandem configuration can have the same bandgap or differing bandgaps.

  9. Solar cell with silicon oxynitride dielectric layer

    DOE Patents [OSTI]

    Shepherd, Michael; Smith, David D

    2015-04-28

    Solar cells with silicon oxynitride dielectric layers and methods of forming silicon oxynitride dielectric layers for solar cell fabrication are described. For example, an emitter region of a solar cell includes a portion of a substrate having a back surface opposite a light receiving surface. A silicon oxynitride (SiO.sub.xN.sub.y, 0silicon oxynitride dielectric layer.

  10. Impact of solid-phase crystallization of amorphous silicon on the chemical structure of the buried Si/ZnO thin film solar cell interface

    SciTech Connect (OSTI)

    Bar, M.; Wimmer, M.; Wilks, R. G.; Roczen, M.; Gerlach, D.; Ruske, F.; Lips, K.; Rech, B.; Weinhardt, L.; Blum, M.; Pookpanratana, S.; Krause, S.; Zhang, Y.; Heske, C.; Yang, W.; Denlinger, J. D.

    2010-04-30

    The chemical interface structure between phosphorus-doped hydrogenated amorphous silicon and aluminum-doped zinc oxide thin films is investigated with soft x-ray emission spectroscopy (XES) before and after solid-phase crystallization (SPC) at 600C. In addition to the expected SPC-induced phase transition from amorphous to polycrystalline silicon, our XES data indicates a pronounced chemical interaction at the buried Si/ZnO interface. In particular, we find an SPC-enhanced formation of Si-O bonds and the accumulation of Zn in close proximity to the interface. For an assumed closed and homogeneous SiO2 interlayer, an effective thickness of (5+2)nm after SPC could be estimated.

  11. Thin film solar energy collector

    DOE Patents [OSTI]

    Aykan, Kamran (Monmouth Beach, NJ); Farrauto, Robert J. (Westfield, NJ); Jefferson, Clinton F. (Millburn, NJ); Lanam, Richard D. (Westfield, NJ)

    1983-11-22

    A multi-layer solar energy collector of improved stability comprising: (1) a substrate of quartz, silicate glass, stainless steel or aluminum-containing ferritic alloy; (2) a solar absorptive layer comprising silver, copper oxide, rhodium/rhodium oxide and 0-15% by weight of platinum; (3) an interlayer comprising silver or silver/platinum; and (4) an optional external anti-reflective coating, plus a method for preparing a thermally stable multi-layered solar collector, in which the absorptive layer is undercoated with a thin film of silver or silver/platinum to obtain an improved conductor-dielectric tandem.

  12. Fabricating solar cells with silicon nanoparticles

    DOE Patents [OSTI]

    Loscutoff, Paul; Molesa, Steve; Kim, Taeseok

    2014-09-02

    A laser contact process is employed to form contact holes to emitters of a solar cell. Doped silicon nanoparticles are formed over a substrate of the solar cell. The surface of individual or clusters of silicon nanoparticles is coated with a nanoparticle passivation film. Contact holes to emitters of the solar cell are formed by impinging a laser beam on the passivated silicon nanoparticles. For example, the laser contact process may be a laser ablation process. In that case, the emitters may be formed by diffusing dopants from the silicon nanoparticles prior to forming the contact holes to the emitters. As another example, the laser contact process may be a laser melting process whereby portions of the silicon nanoparticles are melted to form the emitters and contact holes to the emitters.

  13. Japan Solar Silicon Co Ltd JSS | Open Energy Information

    Open Energy Info (EERE)

    Solar Silicon Co Ltd JSS Jump to: navigation, search Name: Japan Solar Silicon Co Ltd (JSS) Place: Tokyo, Japan Sector: Solar Product: A JV company between Chisso, Nippon Mining...

  14. APIVT-Grown Silicon Thin Layers and PV Devices: Preprint

    SciTech Connect (OSTI)

    Wang, T. H.; Ciszek, T. F.; Page, M. R.; Bauer, R. E.; Wang, Q.; Landry, M. D.

    2002-05-01

    Large-grained (5-20 ..mu..m) polycrystalline silicon layers have been grown at intermediate temperatures of 750-950C directly on foreign substrates without a seeding layer by iodine vapor transport at atmospheric pressure with rates as high as 3 mm/min. A model is constructed to explain the atypical temperature dependence of growth rate. We have also used this technique to grow high-quality epitaxial layers on heavily doped CZ-Si and on upgraded MG-Si substrates. Possible solar cell structures of thin-layer polycrystalline silicon on foreign substrates with light trapping have been examined, compared, and optimized by two-dimensional device simulations. The effects of grain boundary re-combination on device performance are presented for two grain sizes of 2 and 20 mm. We found that 104 cm/s recombination velocity is adequate for 20-m m grain-sized thin silicon, whereas a very low recombination velocity of 103 cm/s must be accomplished in order to achieve reasonable performance for a 2- mm grain-sized polycrystalline silicon device.

  15. Arrays of ultrathin silicon solar microcells

    DOE Patents [OSTI]

    Rogers, John A; Rockett, Angus A; Nuzzo, Ralph; Yoon, Jongseung; Baca, Alfred

    2014-03-25

    Provided are solar cells, photovoltaics and related methods for making solar cells, wherein the solar cell is made of ultrathin solar grade or low quality silicon. In an aspect, the invention is a method of making a solar cell by providing a solar cell substrate having a receiving surface and assembling a printable semiconductor element on the receiving surface of the substrate via contact printing. The semiconductor element has a thickness that is less than or equal to 100 .mu.m and, for example, is made from low grade Si.

  16. Arrays of ultrathin silicon solar microcells

    SciTech Connect (OSTI)

    Rogers, John A.; Rockett, Angus A.; Nuzzo, Ralph; Yoon, Jongseung; Baca, Alfred

    2015-08-11

    Provided are solar cells, photovoltaics and related methods for making solar cells, wherein the solar cell is made of ultrathin solar grade or low quality silicon. In an aspect, the invention is a method of making a solar cell by providing a solar cell substrate having a receiving surface and assembling a printable semiconductor element on the receiving surface of the substrate via contact printing. The semiconductor element has a thickness that is less than or equal to 100 .mu.m and, for example, is made from low grade Si.

  17. Manufacture of silicon carbide using solar energy

    DOE Patents [OSTI]

    Glatzmaier, Gregory C. (Boulder, CO)

    1992-01-01

    A method is described for producing silicon carbide particles using solar energy. The method is efficient and avoids the need for use of electrical energy to heat the reactants. Finely divided silica and carbon are admixed and placed in a solar-heated reaction chamber for a time sufficient to cause a reaction between the ingredients to form silicon carbide of very small particle size. No grinding of silicon carbide is required to obtain small particles. The method may be carried out as a batch process or as a continuous process.

  18. Compensated amorphous-silicon solar cell

    DOE Patents [OSTI]

    Devaud, G.

    1982-06-21

    An amorphous silicon solar cell including an electrically conductive substrate, a layer of glow discharge deposited hydrogenated amorphous silicon having regions of differing conductivity with at least one region of intrinsic hydrogenated amorphous silicon. The layer of hydrogenated amorphous silicon has opposed first and second major surfaces where the first major surface contacts the elecrically conductive substrate and an electrode for electrically contacting the second major surface. The intrinsic hydrogenated amorphous silicon region is deposited in a glow discharge with an atmosphere which includes not less than about 0.02 atom percent mono-atomic boron. An improved N.I.P. solar cell is disclosed using a BF/sub 3/ doped intrinsic layer.

  19. Three dimensional amorphous silicon/microcrystalline silicon solar cells

    DOE Patents [OSTI]

    Kaschmitter, James L.

    1996-01-01

    Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/.mu.c-Si) solar cells which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell.

  20. Three dimensional amorphous silicon/microcrystalline silicon solar cells

    DOE Patents [OSTI]

    Kaschmitter, J.L.

    1996-07-23

    Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/{micro}c-Si) solar cells are disclosed which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell. 4 figs.

  1. GCL Solar Energy Technology Holdings formerly GCL Silicon aka...

    Open Energy Info (EERE)

    GCL Silicon aka Jiangsu Zhongneng Polysilicon Jump to: navigation, search Name: GCL Solar Energy Technology Holdings (formerly GCL Silicon, aka Jiangsu Zhongneng Polysilicon)...

  2. Low Cost, High Efficiency Tandem Silicon Solar Cells and LEDs...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    higher than those of simple multi or single crystalline silicon cells. While three junction non-silicon tandem solar cells have achieved unconcentrated efficiencies of up to...

  3. Thin Silicon MEMS Contact-Stress Sensor Kotovksy, J; Tooker,...

    Office of Scientific and Technical Information (OSTI)

    A; Horsley, D 42 ENGINEERING; 42 ENGINEERING; ACCURACY; ACTUATORS; SILICON This thin, MEMS contact-stress sensor continuously and accurately measures time-varying, solid...

  4. Thin Silicon MEMS Contact-Stress Sensor Kotovsky, J; Tooker,...

    Office of Scientific and Technical Information (OSTI)

    ACCURACY; ACTUATORS; CALIBRATION; DIAPHRAGM; SILICON; STABILITY; THICKNESS This thin, MEMS contact-stress (CS) sensor continuously and accurately measures time-varying, solid...

  5. Thin Silicon MEMS Contact-Stress Sensor Kotovsky, J; Tooker,...

    Office of Scientific and Technical Information (OSTI)

    LIFETIME; PACKAGING; PERFORMANCE; SILICON; THICKNESS This work offers the first, thin, MEMS contact-stress (CS) sensor capable of accurate in situ measruement of time-varying,...

  6. Method of casting silicon into thin sheets

    DOE Patents [OSTI]

    Sanjurjo, Angel; Rowcliffe, David J.; Bartlett, Robert W.

    1982-10-26

    Silicon (Si) is cast into thin shapes within a flat-bottomed graphite crucible by providing a melt of molten Si along with a relatively small amount of a molten salt, preferably NaF. The Si in the resulting melt forms a spherical pool which sinks into and is wetted by the molten salt. Under these conditions the Si will not react with any graphite to form SiC. The melt in the crucible is pressed to the desired thinness with a graphite tool at which point the tool is held until the mass in the crucible has been cooled to temperatures below the Si melting point, at which point the Si shape can be removed.

  7. Harmful Shunting Mechanisms Found in Silicon Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    Scientists developed near-field optical microscopy for imaging electrical breakdown in solar cells and identified critical electrical breakdown mechanisms operating in industrial silicon and epitaxial silicon solar cells.

  8. Metal electrode for amorphous silicon solar cells

    DOE Patents [OSTI]

    Williams, Richard (Princeton, NJ)

    1983-01-01

    An amorphous silicon solar cell having an N-type region wherein the contact to the N-type region is composed of a material having a work function of about 3.7 electron volts or less. Suitable materials include strontium, barium and magnesium and rare earth metals such as gadolinium and yttrium.

  9. Indium oxide/n-silicon heterojunction solar cells

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1982-12-28

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  10. Atomic-Layer-Deposited Transparent Electrodes for Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Demaurex, Benedicte; Seif, Johannes P.; Smit, Sjoerd; Macco, Bart; Kessels, W. M.; Geissbuhler, Jonas; De Wolf, Stefaan; Ballif, Christophe

    2014-11-01

    We examine damage-free transparent-electrode deposition to fabricate high-efficiency amorphous silicon/crystalline silicon heterojunction solar cells. Such solar cells usually feature sputtered transparent electrodes, the deposition of which may damage the layers underneath. Using atomic layer deposition, we insert thin protective films between the amorphous silicon layers and sputtered contacts and investigate their effect on device operation. We find that a 20-nm-thick protective layer suffices to preserve, unchanged, the amorphous silicon layers beneath. Insertion of such protective atomic-layer-deposited layers yields slightly higher internal voltages at low carrier injection levels. However, we identify the presence of a silicon oxide layer, formed during processing, between the amorphous silicon and the atomic-layer-deposited transparent electrode that acts as a barrier, impeding hole and electron collection.

  11. Atomic-Layer-Deposited Transparent Electrodes for Silicon Heterojunction Solar Cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Demaurex, Benedicte; Seif, Johannes P.; Smit, Sjoerd; Macco, Bart; Kessels, W. M.; Geissbuhler, Jonas; De Wolf, Stefaan; Ballif, Christophe

    2014-11-01

    We examine damage-free transparent-electrode deposition to fabricate high-efficiency amorphous silicon/crystalline silicon heterojunction solar cells. Such solar cells usually feature sputtered transparent electrodes, the deposition of which may damage the layers underneath. Using atomic layer deposition, we insert thin protective films between the amorphous silicon layers and sputtered contacts and investigate their effect on device operation. We find that a 20-nm-thick protective layer suffices to preserve, unchanged, the amorphous silicon layers beneath. Insertion of such protective atomic-layer-deposited layers yields slightly higher internal voltages at low carrier injection levels. However, we identify the presence of a silicon oxide layer, formed during processing,more » between the amorphous silicon and the atomic-layer-deposited transparent electrode that acts as a barrier, impeding hole and electron collection.« less

  12. Efficiency of silicon solar cells containing chromium

    DOE Patents [OSTI]

    Frosch, Robert A. Administrator of the National Aeronautics and Space; Salama, Amal M.

    1982-01-01

    Efficiency of silicon solar cells containing about 10.sup.15 atoms/cm.sup.3 of chromium is improved about 26% by thermal annealing of the silicon wafer at a temperature of 200.degree. C. to form chromium precipitates having a diameter of less than 1 Angstrom. Further improvement in efficiency is achieved by scribing laser lines onto the back surface of the wafer at a spacing of at least 0.5 mm and at a depth of less than 13 micrometers to preferentially precipitate chromium near the back surface and away from the junction region of the device. This provides an economical way to improve the deleterious effects of chromium, one of the impurities present in metallurgical grade silicon material.

  13. Origami-enabled deformable silicon solar cells

    SciTech Connect (OSTI)

    Tang, Rui; Huang, Hai; Liang, Hanshuang; Liang, Mengbing; Tu, Hongen; Xu, Yong; Song, Zeming; Jiang, Hanqing; Yu, Hongyu

    2014-02-24

    Deformable electronics have found various applications and elastomeric materials have been widely used to reach flexibility and stretchability. In this Letter, we report an alternative approach to enable deformability through origami. In this approach, the deformability is achieved through folding and unfolding at the creases while the functional devices do not experience strain. We have demonstrated an example of origami-enabled silicon solar cells and showed that this solar cell can reach up to 644% areal compactness while maintaining reasonable good performance upon cyclic folding/unfolding. This approach opens an alternative direction of producing flexible, stretchable, and deformable electronics.

  14. Synthesis and tribological behavior of silicon oxycarbonitride thin films

    Office of Scientific and Technical Information (OSTI)

    derived from poly(urea)methyl vinyl silazane. (Journal Article) | SciTech Connect Journal Article: Synthesis and tribological behavior of silicon oxycarbonitride thin films derived from poly(urea)methyl vinyl silazane. Citation Details In-Document Search Title: Synthesis and tribological behavior of silicon oxycarbonitride thin films derived from poly(urea)methyl vinyl silazane. No abstract prepared. Authors: Prasad, Somuri V. ; Tallant, David Robert ; Raj, Rishi [1] ; Cross, Tsali + Show

  15. Project Profile: Development and Productization of High-Efficiency, Low-Cost Building-Integrated PV Shingles Using Monocrystalline Silicon Thin-Film Solar Cells

    Broader source: Energy.gov [DOE]

    The Solexel-OC team is developing a BIPV roofing shingle product that includes low-profile solar modules and a unique attachment system that will be fastened directly to the roof and incorporates...

  16. And the Award Goes to... Silicon Ink Solar Technology Supported...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    When paired with Innovalight's industrial screen printing process, this silicon ink technology offers a novel path to producing solar cells with higher conversion efficiencies at ...

  17. Solar Fabrik Silicon Services Ltd formerly OJAS Energy | Open...

    Open Energy Info (EERE)

    Energy Jump to: navigation, search Name: Solar-Fabrik Silicon Services Ltd (formerly OJAS Energy) Place: Chennai, India Product: PV wafer manufacturer, legally based in the British...

  18. Thin film solar energy collector

    SciTech Connect (OSTI)

    Farrauto, R.J.; Myers, H.; Williams, J.C.

    1982-03-23

    A solar energy collector has improved absorptance and emissivity levels comprising: (1) a silver-copper oxide-rhodium oxide solar absorption film, (2) a cerium oxide interlayer and a substrate of quartz, silica glass or metal. The cerium oxide interlayer minimizes agglomeration of the metal particles, maintains a relatively low thermal emittance and improves overall stability.

  19. Joint Solar Silicon GmbH Co KG JSSI | Open Energy Information

    Open Energy Info (EERE)

    Name: Joint Solar Silicon GmbH & Co KG (JSSI) Place: Germany Sector: Solar Product: Joint venture between Degussa and SolarWorld for the production of solar-grade silicon on...

  20. Metal catalyst technique for texturing silicon solar cells

    DOE Patents [OSTI]

    Ruby, Douglas S. (Albuquerque, NM); Zaidi, Saleem H. (Albuquerque, NM)

    2001-01-01

    Textured silicon solar cells and techniques for their manufacture utilizing metal sources to catalyze formation of randomly distributed surface features such as nanoscale pyramidal and columnar structures. These structures include dimensions smaller than the wavelength of incident light, thereby resulting in a highly effective anti-reflective surface. According to the invention, metal sources present in a reactive ion etching chamber permit impurities (e.g. metal particles) to be introduced into a reactive ion etch plasma resulting in deposition of micro-masks on the surface of a substrate to be etched. Separate embodiments are disclosed including one in which the metal source includes one or more metal-coated substrates strategically positioned relative to the surface to be textured, and another in which the walls of the reaction chamber are pre-conditioned with a thin coating of metal catalyst material.

  1. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Wednesday, 26 October 2005 00:00 Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a

  2. Thin film absorber for a solar collector

    DOE Patents [OSTI]

    Wilhelm, William G. (Cutchogue, NY)

    1985-01-01

    This invention pertains to energy absorbers for solar collectors, and more particularly to high performance thin film absorbers. The solar collectors comprising the absorber of this invention overcome several problems seen in current systems, such as excessive hardware, high cost and unreliability. In the preferred form, the apparatus features a substantially rigid planar frame with a thin film window bonded to one planar side of the frame. An absorber in accordance with the present invention is comprised of two thin film layers that are sealed perimetrically. In a preferred embodiment, thin film layers are formed from a metal/plastic laminate. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. The absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

  3. Solar cell structure incorporating a novel single crystal silicon material

    DOE Patents [OSTI]

    Pankove, Jacques I. (Princeton, NJ); Wu, Chung P. (Trenton, NJ)

    1983-01-01

    A novel hydrogen rich single crystal silicon material having a band gap energy greater than 1.1 eV can be fabricated by forming an amorphous region of graded crystallinity in a body of single crystalline silicon and thereafter contacting the region with atomic hydrogen followed by pulsed laser annealing at a sufficient power and for a sufficient duration to recrystallize the region into single crystal silicon without out-gassing the hydrogen. The new material can be used to fabricate semiconductor devices such as single crystal silicon solar cells with surface window regions having a greater band gap energy than that of single crystal silicon without hydrogen.

  4. Defect behavior of polycrystalline solar cell silicon

    SciTech Connect (OSTI)

    Schroder, D.K.; Park, S.H.; Hwang, I.G.; Mohr, J.B.; Hanly, M.P.

    1993-05-01

    The major objective of this study, conducted from October 1988 to September 1991, was to gain an understanding of the behavior of impurities in polycrystalline silicon and the influence of these impurities on solar cell efficiency. The authors studied edge-defined film-fed growth (EFG) and cast poly-Si materials and solar cells. With EFG Si they concentrated on chromium-doped materials and cells to determine the role of Cr on solar cell performance. Cast poly-Si samples were not deliberately contaminated. Samples were characterized by cell efficiency, current-voltage, deep-level transient spectroscopy (DLTS), surface photovoltage (SPV), open-circuit voltage decay, secondary ion mass spectrometry, and Fourier transform infrared spectroscopy measurements. They find that Cr forms Cr-B pairs with boron at room temperature and these pairs dissociate into Cr{sub i}{sup +} and B{sup {minus}} during anneals at 210{degrees}C for 10 min. Following the anneal, Cr-B pairs reform at room temperature with a time constant of 230 h. Chromium forms CrSi{sub 2} precipitates in heavily contaminated regions and they find evidence of CrSi{sub 2} gettering, but a lack of chromium segregation or precipitation to grain boundaries and dislocations. Cr-B pairs have well defined DLTS peaks. However, DLTS spectra of other defects are not well defined, giving broad peaks indicative of defects with a range of energy levels in the band gap. In some high-stress, low-efficiency cast poly-Si they detect SiC precipitates, but not in low-stress, high-efficiency samples. SPV measurements result in nonlinear SPV curves in some materials that are likely due to varying optical absorption coefficients due to locally varying stress in the material.

  5. Fabricating amorphous silicon solar cells by varying the temperature _of the substrate during deposition of the amorphous silicon layer

    DOE Patents [OSTI]

    Carlson, David E. (Yardley, PA)

    1982-01-01

    An improved process for fabricating amorphous silicon solar cells in which the temperature of the substrate is varied during the deposition of the amorphous silicon layer is described. Solar cells manufactured in accordance with this process are shown to have increased efficiencies and fill factors when compared to solar cells manufactured with a constant substrate temperature during deposition of the amorphous silicon layer.

  6. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, T.F.

    1998-07-28

    A substrate is described for a photovoltaic device wherein the substrate is the base upon which photosensitive material is to be grown and the substrate comprises an alloy having boron in a range from 0.1 atomic % of the alloy to 1.3 atomic % of the alloy and the substrate has a resistivity less than 3{times}10{sup {minus}3} ohm-cm. 4 figs.

  7. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, Theodore F. (Evergreen, CO)

    1998-01-01

    A substrate for a photovoltaic device wherein the substrate is the base upon which photosensitive material is to be grown and the substrate comprises an alloy having boron in a range from 0.1 atomic % of the alloy to 1.3 atomic % of the alloy and the substrate has a resistivity less than 3.times.10.sup.-3 ohm-cm.

  8. Investigation of the texture surface silicon solar cell

    SciTech Connect (OSTI)

    Rongqiang, C.; Huilan, Q.

    1983-10-01

    The optical and electrical properties of the texture surface silicon solar cell are analyzed and discussed. A new method of etching a texture surface by LiOH is presented and the mechanism of etching a texture surface is investigated.

  9. Silicon Valley Power- Solar Electric Buy Down Program

    Broader source: Energy.gov [DOE]

    Silicon Valley Power (SVP) offers incentives for the installation of new grid-connected solar electric (photovoltaic, or PV) systems. Incentive levels will step down over the life of the program...

  10. GaP/Silicon Tandem Solar Cell with Extended Temperature Range...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    crystalline silicon (Si) substrate, offering lower weight and lower cost. GRC's multi-junction solar cell has bottom solar cell junctions of silicon and a top solar cell junction...

  11. Cost-Effective Silicon Wafers for Solar Cells: Direct Wafer Enabling Terawatt Photovoltaics

    SciTech Connect (OSTI)

    2010-01-15

    Broad Funding Opportunity Announcement Project: 1366 is developing a process to reduce the cost of solar electricity by up to 50% by 2020from $0.15 per kilowatt hour to less than $0.07. 1366s process avoids the costly step of slicing a large block of silicon crystal into wafers, which turns half the silicon to dust. Instead, the company is producing thin wafers directly from molten silicon at industry-standard sizes, and with efficiencies that compare favorably with todays state-of-the-art technologies. 1366s wafers could directly replace wafers currently on the market, so there would be no interruptions to the delivery of these products to market. As a result of 1366s technology, the cost of silicon wafers could be reduced by 80%.

  12. Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Boccard, Mathieu; Holman, Zachary C.

    2015-08-14

    With this study, amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphousmore » silicon carbide being shown to surpass amorphous silicon for temperatures above 300°C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.« less

  13. Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells

    SciTech Connect (OSTI)

    Boccard, Mathieu; Holman, Zachary C.

    2015-08-14

    With this study, amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphous silicon carbide being shown to surpass amorphous silicon for temperatures above 300C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.

  14. Laterally inherently thin amorphous-crystalline silicon heterojunction photovoltaic cell

    SciTech Connect (OSTI)

    Chowdhury, Zahidur R. Kherani, Nazir P.

    2014-12-29

    This article reports on an amorphous-crystalline silicon heterojunction photovoltaic cell concept wherein the heterojunction regions are laterally narrow and distributed amidst a backdrop of well-passivated crystalline silicon surface. The localized amorphous-crystalline silicon heterojunctions consisting of the laterally thin emitter and back-surface field regions are precisely aligned under the metal grid-lines and bus-bars while the remaining crystalline silicon surface is passivated using the recently proposed facile grown native oxideplasma enhanced chemical vapour deposited silicon nitride passivation scheme. The proposed cell concept mitigates parasitic optical absorption losses by relegating amorphous silicon to beneath the shadowed metallized regions and by using optically transparent passivation layer. A photovoltaic conversion efficiency of 13.6% is obtained for an untextured proof-of-concept cell illuminated under AM 1.5 global spectrum; the specific cell performance parameters are V{sub OC} of 666?mV, J{sub SC} of 29.5?mA-cm{sup ?2}, and fill-factor of 69.3%. Reduced parasitic absorption, predominantly in the shorter wavelength range, is confirmed with external quantum efficiency measurement.

  15. Copper doped polycrystalline silicon solar cell

    DOE Patents [OSTI]

    Lovelace, Alan M. Administrator of the National Aeronautics and Space (La Canada, CA); Koliwad, Krishna M. (La Canada, CA); Daud, Taher (La Crescenta, CA)

    1981-01-01

    Photovoltaic cells having improved performance are fabricated from polycrystalline silicon containing copper segregated at the grain boundaries.

  16. Formation of thin-film resistors on silicon substrates

    DOE Patents [OSTI]

    Schnable, George L. (Montgomery County, PA); Wu, Chung P. (Hamilton Township, Mercer County, NJ)

    1988-11-01

    The formation of thin-film resistors by the ion implantation of a metallic conductive layer in the surface of a layer of phosphosilicate glass or borophosphosilicate glass which is deposited on a silicon substrate. The metallic conductive layer materials comprise one of the group consisting of tantalum, ruthenium, rhodium, platinum and chromium silicide. The resistor is formed and annealed prior to deposition of metal, e.g. aluminum, on the substrate.

  17. NREL Develops ZnSiP2 for Silicon-Based Tandem Solar Cells (Fact...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    an Earth-abundant chalcopyrite with a silicon layer could significantly boost conversion efficiency above that of single-junction silicon solar cells. A current technological...

  18. NREL Develops ZnSiP2 for Silicon-Based Tandem Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-08-01

    Combining an Earth-abundant chalcopyrite with a silicon layer could significantly boost conversion efficiency above that of single-junction silicon solar cells.

  19. Solar Thin Films Inc formerly American United Global Inc | Open...

    Open Energy Info (EERE)

    Films Inc formerly American United Global Inc Jump to: navigation, search Name: Solar Thin Films Inc (formerly American United Global Inc) Place: New York, New York Zip: 10038...

  20. Tax Credits Give Thin-Film Solar a Big Boost

    Broader source: Energy.gov [DOE]

    California company will expand its capacity to make its thin-film solar panels by more than ten times, thanks to two Recovery Act tax credits.

  1. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  2. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  3. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  4. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  5. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  6. Engineering Metal Impurities in Multicrystalline Silicon Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Engineering Metal Impurities in Multicrystalline Silicon Solar Cells Print Transition metals are one of the main culprits in degrading the efficiency of multicrystalline solar cells. With a suite of x-ray microprobe techniques, a multi-institutional collaboration led by researchers from the University of California, Berkeley, and Berkeley Lab studied the distribution of metal clusters in a variety of multicrystalline solar cells before and after processing. Their discovery that the size, spatial

  7. Transmissive metallic contact for amorphous silicon solar cells

    DOE Patents [OSTI]

    Madan, A.

    1984-11-29

    A transmissive metallic contact for amorphous silicon semiconductors includes a thin layer of metal, such as aluminum or other low work function metal, coated on the amorphous silicon with an antireflective layer coated on the metal. A transparent substrate, such as glass, is positioned on the light reflective layer. The metallic layer is preferably thin enough to transmit at least 50% of light incident thereon, yet thick enough to conduct electricity. The antireflection layer is preferably a transparent material that has a refractive index in the range of 1.8 to 2.2 and is approximately 550A to 600A thick.

  8. Solar EnerTech PAIS Jin Yu Silicon Wuhai Municipal Gvrnt JV ...

    Open Energy Info (EERE)

    Solar EnerTech PAIS Jin Yu Silicon Wuhai Municipal Gvrnt JV Jump to: navigation, search Name: Solar EnerTech, PAIS, Jin Yu Silicon, & Wuhai Municipal Gvrnt JV Place: Inner Mongolia...

  9. PV Crystalox Solar AG formerly PV Silicon AG | Open Energy Information

    Open Energy Info (EERE)

    PV Crystalox Solar AG formerly PV Silicon AG Jump to: navigation, search Name: PV Crystalox Solar AG (formerly PV Silicon AG) Place: Abingdon, England, United Kingdom Zip: OX14 4SE...

  10. Polycrystalline GaAs solar cells on low-cost Silicon-Film{trademark} substrates

    SciTech Connect (OSTI)

    Mauk, M.G.; Feyock, B.W.; Hall, R.B.; Cavanaugh, K.D.; Cotter, J.E.

    1997-12-31

    The authors assess the potential of a low-cost, large-area Silicon-Film{trademark} sheet as a substrate for thin-film polycrystalline GaAs solar cells. Silicon-Film is a relatively inexpensive material on which large-grain (>2 mm) polycrystalline GaAs films can be formed. The GaAs epitaxial layers are grown by a simple close-spaced vapor transport (CSVT) technique using water vapor as a transport agent. A recrystallized Ge{sub 1{minus}x}Si{sub x} buffer layer between the GaAs epilayer and Silicon-Film substrate can facilitate growth of the GaAs. Selective epitaxy on patterned, oxide-masked substrates is effective in reducing thermal stress effects.

  11. The electron beam hole drilling of silicon nitride thin films

    SciTech Connect (OSTI)

    Howitt, D. G.; Chen, S. J.; Gierhart, B. C.; Smith, R. L.; Collins, S. D.

    2008-01-15

    The mechanism by which an intense electron beam can produce holes in thin films of silicon nitride has been investigated using a combination of in situ electron energy loss spectrometry and electron microscopy imaging. A brief review of electron beam interactions that lead to material loss in different materials is also presented. The loss of nitrogen and silicon decreases with decreasing beam energy and although still observable at a beam energy of 150 keV ceases completely at 120 keV. The linear behavior of the loss rate coupled with the energy dependency indicates that the process is primarily one of direct displacement, involving the sputtering of atoms from the back surface of the specimen with the rate controlling mechanism being the loss of nitrogen.

  12. A 2-terminal perovskite/silicon multijunction solar cell enabled by a silicon tunnel junction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mailoa, Jonathan P.; Bailie, Colin D.; Johlin, Eric C.; Hoke, Eric T.; Akey, Austin J.; Nguyen, William H.; McGehee, Michael D.; Buonassisi, Tonio

    2015-03-24

    With the advent of efficient high-bandgap metal-halide perovskite photovoltaics, an opportunity exists to make perovskite/silicon tandem solar cells. We fabricate a monolithic tandem by developing a silicon-based interband tunnel junction that facilitates majority-carrier charge recombination between the perovskite and silicon sub-cells. We demonstrate a 1 cm2 2-terminal monolithic perovskite/silicon multijunction solar cell with a VOC as high as 1.65 V. As a result, we achieve a stable 13.7% power conversion efficiency with the perovskite as the current-limiting sub-cell, and identify key challenges for this device architecture to reach efficiencies over 25%.

  13. A 2-terminal perovskite/silicon multijunction solar cell enabled by a silicon tunnel junction

    SciTech Connect (OSTI)

    Mailoa, Jonathan P.; Bailie, Colin D.; Johlin, Eric C.; Hoke, Eric T.; Akey, Austin J.; Nguyen, William H.; McGehee, Michael D.; Buonassisi, Tonio

    2015-03-24

    With the advent of efficient high-bandgap metal-halide perovskite photovoltaics, an opportunity exists to make perovskite/silicon tandem solar cells. We fabricate a monolithic tandem by developing a silicon-based interband tunnel junction that facilitates majority-carrier charge recombination between the perovskite and silicon sub-cells. We demonstrate a 1 cm2 2-terminal monolithic perovskite/silicon multijunction solar cell with a VOC as high as 1.65 V. As a result, we achieve a stable 13.7% power conversion efficiency with the perovskite as the current-limiting sub-cell, and identify key challenges for this device architecture to reach efficiencies over 25%.

  14. The Silicon Solar Cell Turns 50

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Daryl Chapin, Calvin Fuller, and Gerald Pearson likely never imagined inventing a solar cell that would revolutionize the photovoltaics industry. There wasn't even a photovoltaics...

  15. NREL Success Stories - Quest for Inexpensive Silicon Solar Cells

    ScienceCinema (OSTI)

    Branz, Howard

    2013-05-29

    Scientists at the National Renewable Energy Laboratory (NREL) share their story about a successful partnership with Oak Ridge National Laboratory and the Ampulse Corporation and how support from the US Department of Energy's Technology Commercialization & Deployment Fund has helped it and their silicon solar cell research thrive.

  16. Modelling and fabrication of high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Rohatgi, A.; Smith, A.W.; Salami, J.

    1991-10-01

    This report covers the research conducted on modelling and development of high-efficiency silicon solar cells during the period May 1989 to August 1990. First, considerable effort was devoted toward developing a ray-tracing program for the photovoltaic community to quantify and optimize surface texturing for solar cells. Second, attempts were made to develop a hydrodynamic model for device simulation. Such a model is somewhat slower than drift-diffusion type models like PC-1D, but it can account for more physical phenomena in the device, such as hot carrier effects, temperature gradients, thermal diffusion, and lattice heat flow. In addition, Fermi-Dirac statistics have been incorporated into the model to deal with heavy doping effects more accurately. Third and final component of the research includes development of silicon cell fabrication capabilities and fabrication of high-efficiency silicon cells. 84 refs., 46 figs., 10 tabs.

  17. Silicon Oxynitride Thin Film Barriers for PV Packaging (Poster)

    SciTech Connect (OSTI)

    del Cueto, J. A.; Glick, S. H.; Terwilliger, K. M.; Jorgensen, G. J.; Pankow, J. W.; Keyes, B. M.; Gedvilas, L. M.; Pern, F. J.

    2006-10-03

    Dielectric, adhesion-promoting, moisture barriers comprised of silicon oxynitride thin film materials (SiOxNy with various material stoichiometric compositions x,y) were applied to: 1) bare and pre-coated soda-lime silicate glass (coated with transparent conductive oxide SnO2:F and/or aluminum), and polymer substrates (polyethylene terephthalate, PET, or polyethylene napthalate, PEN); plus 2) pre- deposited photovoltaic (PV) cells and mini-modules consisting of amorphous silicon (a-Si) and copper indium gallium diselenide (CIGS) thin-film PV technologies. We used plasma enhanced chemical vapor deposition (PECVD) process with dilute silane, nitrogen, and nitrous oxide/oxygen gas mixtures in a low-power (< or = 10 milliW per cm2) RF discharge at ~ 0.2 Torr pressure, and low substrate temperatures < or = 100(degrees)C, over deposition areas ~ 1000 cm2. Barrier properties of the resulting PV cells and coated-glass packaging structures were studied with subsequent stressing in damp-heat exposure at 85(degrees)C/85% RH. Preliminary results on PV cells and coated glass indicate the palpable benefits of the barriers in mitigating moisture intrusion and degradation of the underlying structures using SiOxNy coatings with thicknesses in the range of 100-200 nm.

  18. Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Lower Cost | Department of Energy Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost April 18, 2013 - 12:00am Addthis Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost Partnering with Sunnyvale-based Innovalight, which was acquired by DuPont in July 2011, EERE supported the development of the first commercially available liquid silicon offering a

  19. Method for forming indium oxide/n-silicon heterojunction solar cells

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1984-03-13

    A high photo-conversion efficiency indium oxide/n-silicon heterojunction solar cell is spray deposited from a solution containing indium trichloride. The solar cell exhibits an Air Mass One solar conversion efficiency in excess of about 10%.

  20. Overview and Challenges of Thin Film Solar Electric Technologies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Thin Film Solar Electric Technologies H.S. Ullal Presented at the World Renewable Energy Congress X and Exhibition 2008 Glasgow, Scotland, United Kingdom July 19-25, 2008...

  1. Beyond Silicon: Cutting the Costs of Solar Power | U.S. DOE Office of Science (SC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beyond Silicon: Cutting the Costs of Solar Power Stories of Discovery & Innovation Beyond Silicon: Cutting the Costs of Solar Power Enlarge Photo Courtesy of University of Illinois Mechanically flexible, high efficiency solar module that uses an interconnected array of microscale GaAs photovoltaic cells, grown in a multilayer stack on a wafer and then printed onto a sheet of plastic. Enlarge Photo 04.15.11 Beyond Silicon: Cutting the Costs of Solar Power New method of fabricating

  2. Optical limiting effects in nanostructured silicon carbide thin films

    SciTech Connect (OSTI)

    Borshch, A A; Starkov, V N; Volkov, V I; Rudenko, V I; Boyarchuk, A Yu; Semenov, A V

    2013-12-31

    We present the results of experiments on the interaction of nanosecond laser radiation at 532 and 1064 nm with nanostructured silicon carbide thin films of different polytypes. We have found the effect of optical intensity limiting at both wavelengths. The intensity of optical limiting at ? = 532 nm (I{sub cl} ? 10{sup 6} W cm{sup -2}) is shown to be an order of magnitude less than that at ? = 1064 nm (I{sub cl} ? 10{sup 7} W cm{sup -2}). We discuss the nature of the nonlinearity, leading to the optical limiting effect. We have proposed a method for determining the amount of linear and two-photon absorption in material media. (nonlinear optical phenomena)

  3. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Chen, Zhizhang; Doshi, Parag

    1996-01-01

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.

  4. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-01-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n{sup ++} Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  5. Junction Transport in Epitaxial Film Silicon Heterojunction Solar Cells: Preprint

    SciTech Connect (OSTI)

    Young, D. L.; Li, J. V.; Teplin, C. W.; Stradins, P.; Branz, H. M.

    2011-07-01

    We report our progress toward low-temperature HWCVD epitaxial film silicon solar cells on inexpensive seed layers, with a focus on the junction transport physics exhibited by our devices. Heterojunctions of i/p hydrogenated amorphous Si (a-Si) on our n-type epitaxial crystal Si on n++ Si wafers show space-charge-region recombination, tunneling or diffusive transport depending on both epitaxial Si quality and the applied forward voltage.

  6. Method for producing silicon thin-film transistors with enhanced forward current drive

    DOE Patents [OSTI]

    Weiner, Kurt H. (San Jose, CA)

    1998-01-01

    A method for fabricating amorphous silicon thin film transistors (TFTs) with a polycrystalline silicon surface channel region for enhanced forward current drive. The method is particularly adapted for producing top-gate silicon TFTs which have the advantages of both amorphous and polycrystalline silicon TFTs, but without problem of leakage current of polycrystalline silicon TFTs. This is accomplished by selectively crystallizing a selected region of the amorphous silicon, using a pulsed excimer laser, to create a thin polycrystalline silicon layer at the silicon/gate-insulator surface. The thus created polysilicon layer has an increased mobility compared to the amorphous silicon during forward device operation so that increased drive currents are achieved. In reverse operation the polysilicon layer is relatively thin compared to the amorphous silicon, so that the transistor exhibits the low leakage currents inherent to amorphous silicon. A device made by this method can be used, for example, as a pixel switch in an active-matrix liquid crystal display to improve display refresh rates.

  7. Method for producing silicon thin-film transistors with enhanced forward current drive

    DOE Patents [OSTI]

    Weiner, K.H.

    1998-06-30

    A method is disclosed for fabricating amorphous silicon thin film transistors (TFTs) with a polycrystalline silicon surface channel region for enhanced forward current drive. The method is particularly adapted for producing top-gate silicon TFTs which have the advantages of both amorphous and polycrystalline silicon TFTs, but without problem of leakage current of polycrystalline silicon TFTs. This is accomplished by selectively crystallizing a selected region of the amorphous silicon, using a pulsed excimer laser, to create a thin polycrystalline silicon layer at the silicon/gate-insulator surface. The thus created polysilicon layer has an increased mobility compared to the amorphous silicon during forward device operation so that increased drive currents are achieved. In reverse operation the polysilicon layer is relatively thin compared to the amorphous silicon, so that the transistor exhibits the low leakage currents inherent to amorphous silicon. A device made by this method can be used, for example, as a pixel switch in an active-matrix liquid crystal display to improve display refresh rates. 1 fig.

  8. Silicon Ink for High-Efficiency Solar Cells Captures a Share of the Market (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-08-01

    Fact sheet on 2011 R&D 100 Award winner Silicon Ink. Liquid silicon has arrived, and with it comes a power boost for solar cells and dramatic cost savings for cell manufacturers.

  9. Ninth workshop on crystalline silicon solar cell materials and processes: Summary discussion sessions

    SciTech Connect (OSTI)

    Sopori, B.; Tan, T.; Swanson, D.; Rosenblum, M.; Sinton, R.

    1999-11-23

    This report is a summary of the panel discussions included with the Ninth Workshop on Crystalline Silicon Solar Cell Materials and Processes. The theme for the workshop was ``R and D Challenges and Opportunities in Si Photovoltaics.'' This theme was chosen because it appropriately reflects a host of challenges that the growing production of Si photovoltaics will be facing in the new millennium. The anticipated challenges will arise in developing strategies for cost reduction, increased production, higher throughput per manufacturing line, new sources of low-cost Si, and the introduction of new manufacturing processes for cell production. At the same time, technologies based on CdTe and CIS will come on line posing new competition. With these challenges come new opportunities for Si PV to wean itself from the microelectronics industry, to embark on a more aggressive program in thin-film Si solar cells, and to try new approaches to process monitoring.

  10. High-performance porous silicon solar cell development. Final report, October 1, 1993--September 30, 1995

    SciTech Connect (OSTI)

    Maruska, P.

    1996-09-01

    The goal of the program was to demonstrate use of porous silicon in new solar cell structures. Porous silicon technology has been developed at Spire for producing visible light-emitting diodes (LEDs). The major aspects that they have demonstrated are the following: porous silicon active layers have been made to show photovoltaic action; porous silicon surface layers can act as antireflection coatings to improve the performance of single-crystal silicon solar cells; and porous silicon surface layers can act as antireflection coatings on polycrystalline silicon solar cells. One problem with the use of porous silicon is to achieve good lateral conduction of electrons and holes through the material. This shows up in terms of poor blue response and photocurrents which increase with increasing reverse bias applied to the diode.

  11. Ambipolar charge transport in microcrystalline silicon thin-film transistors

    SciTech Connect (OSTI)

    Knipp, Dietmar; Marinkovic, M.; Chan, Kah-Yoong; Gordijn, Aad; Stiebig, Helmut

    2011-01-15

    Hydrogenated microcrystalline silicon ({mu}c-Si:H) is a promising candidate for thin-film transistors (TFTs) in large-area electronics due to high electron and hole charge carrier mobilities. We report on ambipolar TFTs based on {mu}c-Si:H prepared by plasma-enhanced chemical vapor deposition at temperatures compatible with flexible substrates. Electrons and holes are directly injected into the {mu}c-Si:H channel via chromium drain and source contacts. The TFTs exhibit electron and hole charge carrier mobilities of 30-50 cm{sup 2}/V s and 10-15 cm{sup 2}/V s, respectively. In this work, the electrical characteristics of the ambipolar {mu}c-Si:H TFTs are described by a simple analytical model that takes the ambipolar charge transport into account. The analytical expressions are used to model the transfer curves, the potential and the net surface charge along the channel of the TFTs. The electrical model provides insights into the electronic transport of ambipolar {mu}c-Si:H TFTs.

  12. Polycrystalline Thin-Film Multijunction Solar Cells

    SciTech Connect (OSTI)

    Noufi, R.; Wu, X.; Abu-Shama, J.; Ramanathan, K; Dhere, R.; Zhou, J.; Coutts, T.; Contreras, M.; Gessert, T.; Ward, J. S.

    2005-11-01

    We present a digest of our research on the thin-film material components that comprise the top and bottom cells of three different material systems and the tandem devices constructed from them.

  13. AOS Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    AOS Solar Inc Jump to: navigation, search Name: AOS Solar Inc Product: Manufacturer of thin-film silicon-on-glass. References: AOS Solar Inc1 This article is a stub. You can help...

  14. Bangkok Solar Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Bangkok Solar Co Ltd Place: Chachoengsao, Thailand Zip: 24140 Product: Manufacturer of thin-film amorphous silicon modules, distributes in Europe through Reinecke + Pohl....

  15. Silicon-integrated thin-film structure for electro-optic applications

    DOE Patents [OSTI]

    McKee, Rodney A. (Kingston, TN); Walker, Frederick Joseph (Oak Ridge, TN)

    2000-01-01

    A crystalline thin-film structure suited for use in any of an number of electro-optic applications, such as a phase modulator or a component of an interferometer, includes a semiconductor substrate of silicon and a ferroelectric, optically-clear thin film of the perovskite BaTiO.sub.3 overlying the surface of the silicon substrate. The BaTiO.sub.3 thin film is characterized in that substantially all of the dipole moments associated with the ferroelectric film are arranged substantially parallel to the surface of the substrate to enhance the electro-optic qualities of the film.

  16. California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Award | Department of Energy TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award August 16, 2013 - 10:41am Addthis California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon photovoltaic (PV) cell architecture and manufacturing process that achieves

  17. EERE Success Story-California: TetraCell Silicon Solar Cell Improves

    Office of Environmental Management (EM)

    Efficiency, Wins R&D 100 Award | Department of Energy TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award EERE Success Story-California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award August 16, 2013 - 10:41am Addthis EERE Success Story—California: TetraCell Silicon Solar Cell Improves Efficiency, Wins R&D 100 Award TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon

  18. Amorphous silicon solar cells techniques for reactive conditions

    SciTech Connect (OSTI)

    Shimizu, Satoshi; Okawa, Kojiro; Kamiya, Toshio; Fortmann, C.M.; Shimizu, Isamu

    1999-07-01

    The preparation of amorphous silicon films and solar cells using SiH{sub 2}Cl{sub 2} source gas and electron cyclotron resonance assisted chemical vapor deposition (ECR-CVD) was investigated. By using buffer layers to protect previously deposited layers improved a-Si:H(Cl) solar cells were prepared and studied. The high quality a-Si:H(Cl) films used in this study exhibited low defect densities ({approximately}10{sup 15} cm{sup {minus}3}) and high stability under illumination even when the deposition rate was increased to {approximately} 15A/s. The solar cells were deposited in the n-i-p sequence. These solar cells achieved V{sub oc} values of {approximately}0.89V and {approximately}3.9% efficiency on Ga doped ZnO (GZO) coated specular substrate. The a-Si:H(Cl) electron and hole {mu}{tau} products were {approximately}10{sup {minus}8} cm{sup 2}/V.

  19. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, A.; Doshi, P.; Tate, J.K.; Mejia, J.; Chen, Z.

    1998-06-16

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime {tau} and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime {tau} and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO{sub x}. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure. 28 figs.

  20. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Doshi, Parag; Tate, John Keith; Mejia, Jose; Chen, Zhizhang

    1998-06-16

    Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure.

  1. PROJECT PROFILE: Silicon-Based Tandem Solar Cells | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    PROJECT PROFILE: Silicon-Based Tandem Solar Cells PROJECT PROFILE: Silicon-Based Tandem Solar Cells Funding Opportunity: SuNLaMP SunShot Subprogram: Photovoltaics Location: National Renewable Energy Laboratory, Golden, CO Amount Awarded: $1,500,000 The project will demonstrate bonded gallium indium phosphide (GaInP) on silicon tandem cells, evaluate the advantages and disadvantages of this method of forming higher-efficiency tandem cells, and compare two- and three-terminal device

  2. Thin, High Lifetime Silicon Wafers with No Sawing; Re-crystallization in a Thin Film Capsule

    SciTech Connect (OSTI)

    Emanuel Sachs Tonio Buonassisi

    2013-01-16

    The project fits within the area of renewable energy called photovoltaics (PV), or the generation of electricity directly from sunlight using semiconductor devices. PV has the greatest potential of any renewable energy technology. The vast majority of photovoltaic modules are made on crystalline silicon wafers and these wafers accounts for the largest fraction of the cost of a photovoltaic module. Thus, a method of making high quality, low cost wafers would be extremely beneficial to the PV industry The industry standard technology creates wafers by casting an ingot and then sawing wafers from the ingot. Sawing rendered half of the highly refined silicon feedstock as un-reclaimable dust. Being a brittle material, the sawing is actually a type of grinding operation which is costly both in terms of capital equipment and in terms of consumables costs. The consumables costs associated with the wire sawing technology are particularly burdensome and include the cost of the wire itself (continuously fed, one time use), the abrasive particles, and, waste disposal. The goal of this project was to make wafers directly from molten silicon with no sawing required. The fundamental concept was to create a very low cost (but low quality) wafer of the desired shape and size and then to improve the quality of the wafer by a specialized thermal treatment (called re-crystallization). Others have attempted to create silicon sheet by recrystallization with varying degrees of success. Key among the difficulties encountered by others were: a) difficulty in maintaining the physical shape of the sheet during the recrystallization process and b) difficulty in maintaining the cleanliness of the sheet during recrystallization. Our method solved both of these challenges by encapsulating the preform wafer in a protective capsule prior to recrystallization (see below). The recrystallization method developed in this work was extremely effective at maintaining the shape and the cleanliness of the wafer. In addition, it was found to be suitable for growing very large crystals. The equipment used was simple and inexpensive to operate. Reasonable solar cells were fabricated on re-crystallized material.

  3. Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation

    SciTech Connect (OSTI)

    Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter; Fanni, Lorenzo; de Nicolas Agut, Silvia Martin; Geissbuhler, Jonas; Paviet-Salomon, Bertrand; Nicolay, Sylvain; Barraud, Loris; Niesen, Bjoern; De Wolf, Stefaan; Ballif, Christophe

    2015-10-26

    Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solar cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.

  4. Thin-film absorber for a solar collector

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1982-02-09

    This invention pertains to energy absorbers for solar collectors, and more particularly to high performance thin film absorbers. The solar collectors comprising the absorber of this invention overcome several problems seen in current systems, such as excessive hardware, high cost and unreliability. In the preferred form, the apparatus features a substantially rigid planar frame with a thin film window bonded to one planar side of the frame. An absorber in accordance with the present invention is comprised of two thin film layers that are sealed perimetrically. In a preferred embodiment, thin film layers are formed from a metal/plastic laminate. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. The absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

  5. Role of point defects/defect complexes in silicon device processing. Book of abstracts, fourth workshop

    SciTech Connect (OSTI)

    Not Available

    1994-06-01

    The 41 abstracts are arranged into 6 sessions: impurities and defects in commercial substrates: their sources, effects on material yield, and material quality; impurity gettering in silicon: limits and manufacturability of impurity gettering and in silicon solar cells; impurity/defect passivation; new concepts in silicon growth: improved initial quality and thin films; and silicon solar cell design opportunities.

  6. 15th Workshop on Crystalline Silicon Solar Cells and Modules: Materials and Processes; Extended Abstracts and Papers

    SciTech Connect (OSTI)

    Sopori, B. L.

    2005-11-01

    The National Center for Photovoltaics sponsored the 15th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes, held in Vail, CO, August 7-10, 2005. This meeting provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. The workshop addressed the fundamental properties of PV silicon, new solar cell designs, and advanced solar cell processing techniques. A combination of oral presentations by invited speakers, poster sessions, and discussion sessions reviewed recent advances in crystal growth, new cell designs, new processes and process characterization techniques, and cell fabrication approaches suitable for future manufacturing demands. The theme of this year's meeting was 'Providing the Scientific Basis for Industrial Success.' Specific sessions during the workshop included: Advances in crystal growth and material issues; Impurities and defects in Si; Advanced processing; High-efficiency Si solar cells; Thin Si solar cells; and Cell design for efficiency and reliability module operation. The topic for the Rump Session was ''Si Feedstock: The Show Stopper'' and featured a panel discussion by representatives from various PV companies.

  7. 16th Workshop on Crystalline Silicon Solar Cells and Modules: Materials and Processes; Program, Extended Abstracts, and Papers

    SciTech Connect (OSTI)

    Sopori, B. L.

    2006-08-01

    The National Center for Photovoltaics sponsored the 16th Workshop on Crystalline Silicon Solar Cells and Modules: Materials and Processes held August 6-9, 2006 in Denver, Colorado. The workshop addressed the fundamental properties of PV-Si, new solar cell designs, and advanced solar cell processing techniques. It provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. The Workshop Theme was: "Getting more (Watts) for Less ($i)". A combination of oral presentations by invited speakers, poster sessions, and discussion sessions reviewed recent advances in crystal growth, new cell structures, new processes and process characterization techniques, and cell fabrication approaches suitable for future manufacturing demands. The special sessions included: Feedstock Issues: Si Refining and Purification; Metal-impurity Engineering; Thin Film Si; and Diagnostic Techniques.

  8. And the Award Goes to... Silicon Ink Solar Technology Supported by

    Energy Savers [EERE]

    SunShot's PV Incubator | Department of Energy And the Award Goes to... Silicon Ink Solar Technology Supported by SunShot's PV Incubator And the Award Goes to... Silicon Ink Solar Technology Supported by SunShot's PV Incubator July 19, 2011 - 5:00pm Addthis Innovalight’s silicon ink technology | Photo courtesy of Innovalight Innovalight's silicon ink technology | Photo courtesy of Innovalight What does this mean for me? Pioneering startup Innovalight partnered with NREL to invent the

  9. 10th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers from the Workshop, Copper Mountain Resort; August 14-16, 2000

    SciTech Connect (OSTI)

    Sopori, B.L.; Gee, J.; Kalejs, J.; Saitoh, R.; Stavola, M.; Swanson, D.; Tan, T.; Weber, E.; Werner, J.

    2000-08-11

    The 10th Workshop provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and non-photovoltaic fields. Discussions included the various aspects of impurities and defects in silicon-their properties, the dynamics during device processing, and their application for developing low-cost processes for manufacturing high-efficiency silicon solar cells. Sessions and panel discussions also reviewed thin-film crystalline-silicon PV, advanced cell structures, new processes and process characterization techniques, and future manufacturing requirements to meet the ambitious expansion goals described in the recently released US PV Industry Roadmap. The Workshop also provided an excellent opportunity for researchers in private industry and at universities to recognize a mutual need for future collaborative research. The three-day workshop consisted of presentations by invited speakers, followed by discussion sessions. In addition, there was two poster sessions presenting the latest research and development results. The subjects discussed included: solar cell processing, light-induced degradation, gettering and passivation, crystalline silicon growth, thin-film silicon solar cells, and impurities and defects. Two special sessions featured at this workshop: advanced metallization and interconnections, and characterization methods.

  10. Thin film solar cell including a spatially modulated intrinsic layer

    DOE Patents [OSTI]

    Guha, Subhendu (Troy, MI); Yang, Chi-Chung (Troy, MI); Ovshinsky, Stanford R. (Bloomfield Hills, MI)

    1989-03-28

    One or more thin film solar cells in which the intrinsic layer of substantially amorphous semiconductor alloy material thereof includes at least a first band gap portion and a narrower band gap portion. The band gap of the intrinsic layer is spatially graded through a portion of the bulk thickness, said graded portion including a region removed from the intrinsic layer-dopant layer interfaces. The band gap of the intrinsic layer is always less than the band gap of the doped layers. The gradation of the intrinsic layer is effected such that the open circuit voltage and/or the fill factor of the one or plural solar cell structure is enhanced.

  11. Solar Grade Silicon from Agricultural By-products

    SciTech Connect (OSTI)

    Richard M. Laine

    2012-08-20

    In this project, Mayaterials developed a low cost, low energy and low temperature method of purifying rice hull ash to high purity (5-6Ns) and converting it by carbothermal reduction to solar grade quality silicon (Sipv) using a self-designed and built electric arc furnace (EAF). Outside evaluation of our process by an independent engineering firm confirms that our technology greatly lowers estimated operating expenses (OPEX) to $5/kg and capital expenses (CAPEX) to $24/kg for Sipv production, which is well below best-in-class plants using a Siemens process approach (OPEX of 14/kg and CAPEX of $87/kg, respectively). The primary limiting factor in the widespread use of photovoltaic (PV) cells is the high cost of manufacturing, compared to more traditional sources to reach 6 g Sipv/watt (with averages closer to 8+g/watt). In 2008, the spot price of Sipv rose to $450/kg. While prices have since dropped to a more reasonable $25/kg; this low price level is not sustainable, meaning the longer-term price will likely return to $35/kg. The 6-8 g Si/watt implies that the Sipv used in a module will cost $0.21-0.28/watt for the best producers (45% of the cost of a traditional solar panel), a major improvement from the cost/wafer driven by the $50/kg Si costs of early 2011, but still a major hindrance in fulfilling DOE goal of lowering the cost of solar energy below $1/watt. The solar cell industry has grown by 40% yearly for the past eight years, increasing the demand for Sipv. As such, future solar silicon price spikes are expected in the next few years. Although industry has invested billions of dollars to meet this ever-increasing demand, the technology to produce Sipv remains largely unchanged requiring the energy intensive, and chlorine dependent Siemens process or variations thereof. While huge improvements have been made, current state-of-the-art industrial plant still use 65 kWh/kg of silicon purified. Our technology offers a key distinction to other technologies as it starts one step upstream from all other Sipv production efforts. Our process starts by producing high purity SiO2/C feedstocks from which Sipv can be produced in a single, chlorine free, final EAF step. Specifically, our unique technology, and the resultant SiO2/C product can serve as high purity feedstocks to existing metallurgical silicon (Simet) producers, allowing them to generate Sipv with existing US manufacturing infrastructure, reducing the overall capital and commissioning schedule. Our low energy, low CAPEX and OPEX process purifies the silica and carbon present in rice hull ash (RHA) at low temperatures (< 200C) to produce high purity (5-6 Ns) feedstock for production of Sipv using furnaces similar to those used to produce Simet. During the course of this project we partnered with Wadham Energy LP (Wadham), who burns 220k ton of rice hulls (RH)/yr generating 200 GWh of electricity/yr and >30k ton/yr RHA. The power generation step produces much more energy (42 kWh/kg of final silicon produced) than required to purify the RHA (5 kWh/kg of Sipv, compared to 65 kWh/kg noted above. Biogenic silica offers three very important foundations for producing high purity silicon. First, wastes from silica accumulating plants, such as rice, corn, many grasses, algae and grains, contain very reactive, amorphous silica from which impurities are easily removed. Second, plants take up only a limited set of, and minimal quantities of the heavy metals present in nature, meaning fewer minerals must be removed. Third, biomass combustion generates a product with intrinsic residual carbon, mixed at nanometer length scales with the SiO2. RHA is 80-90 wt% high surface area (20 m2/g), amorphous SiO2 with some simple mineral content mixed intimately with 5-15 wt% carbon. The mineral content is easily removed by low cost, acid washes using Mayaterials IP, leading to purified rice hull ash (RHAclean) at up to 6N purity. This highly reactive silica is partially extracted from RHAclean at 200 C in an environmentally benign process to adjust SiO2:C ratios to those needed in EA

  12. PowerFilm Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc Place: Boone, Iowa Zip: 50036 7538 Product: Developer of a method for manufacturing thin-film amorphous silicon modules, from silane gas and plastic substrate, using...

  13. Genesis Solar Singapore formerly STP Production | Open Energy...

    Open Energy Info (EERE)

    search Name: Genesis Solar Singapore (formerly STP Production) Place: Singapore Product: Thin-film silicon PV company in Singapore, in which a 75% stake was bought by Genesis...

  14. Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter; Fanni, Lorenzo; de Nicolas Agut, Silvia Martin; Geissbuhler, Jonas; Paviet-Salomon, Bertrand; Nicolay, Sylvain; Barraud, Loris; Niesen, Bjoern; et al

    2015-10-26

    Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solarmore » cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.« less

  15. Silicon Solar Cells with Front Hetero-Contact and Aluminum Alloy Back Junction: Preprint

    SciTech Connect (OSTI)

    Yuan, H.-C.; Page, M. R.; Iwaniczko, E.; Xu, Y.; Roybal, L.; Wang, Q.; Branz, H. M.; Meier, D. L.

    2008-05-01

    We prototype an alternative n-type monocrystalline silicon (c-Si) solar cell structure that utilizes an n/i-type hydrogenated amorphous silicon (a-Si:H) front hetero-contact and a back p-n junction formed by alloying aluminum (Al) with the n-type Si wafer.

  16. Amorphous silicon enhanced metal-insulator-semiconductor contacts for silicon solar cells

    SciTech Connect (OSTI)

    Bullock, J. Cuevas, A.; Yan, D.; Demaurex, B.; Hessler-Wyser, A.; De Wolf, S.

    2014-10-28

    Carrier recombination at the metal-semiconductor contacts has become a significant obstacle to the further advancement of high-efficiency diffused-junction silicon solar cells. This paper provides the proof-of-concept of a procedure to reduce contact recombination by means of enhanced metal-insulator-semiconductor (MIS) structures. Lightly diffused n{sup +} and p{sup +} surfaces are passivated with SiO{sub 2}/a-Si:H and Al{sub 2}O{sub 3}/a-Si:H stacks, respectively, before the MIS contacts are formed by a thermally activated alloying process between the a-Si:H layer and an overlying aluminum film. Transmission/scanning transmission electron microscopy (TEM/STEM) and energy dispersive x-ray spectroscopy are used to ascertain the nature of the alloy. Idealized solar cell simulations reveal that MIS(n{sup +}) contacts, with SiO{sub 2} thicknesses of ?1.55?nm, achieve the best carrier-selectivity producing a contact resistivity ?{sub c} of ?3 m? cm{sup 2} and a recombination current density J{sub 0c} of ?40 fA/cm{sup 2}. These characteristics are shown to be stable at temperatures up to 350?C. The MIS(p{sup +}) contacts fail to achieve equivalent results both in terms of thermal stability and contact characteristics but may still offer advantages over directly metallized contacts in terms of manufacturing simplicity.

  17. Microstructure of amorphous-silicon-based solar cell materials by small-angle x-ray scattering. Annual subcontract report, 6 April 1994--5 April 1995

    SciTech Connect (OSTI)

    Williamson, D.L.

    1995-08-01

    The general objective of this research is to provide detailed microstructural information on the amorphous-silicon-based, thin-film materials under development for improved multijunction solar cells. The experimental technique used is small-angle x-ray scattering (SAXS) providing microstructural data on microvoid fractions, sizes, shapes, and their preferred orientations. Other microstructural features such as alloy segregation, hydrogen-rich clusters and alloy short-range order are probed.

  18. Methods for fabricating thin film III-V compound solar cell

    DOE Patents [OSTI]

    Pan, Noren; Hillier, Glen; Vu, Duy Phach; Tatavarti, Rao; Youtsey, Christopher; McCallum, David; Martin, Genevieve

    2011-08-09

    The present invention utilizes epitaxial lift-off in which a sacrificial layer is included in the epitaxial growth between the substrate and a thin film III-V compound solar cell. To provide support for the thin film III-V compound solar cell in absence of the substrate, a backing layer is applied to a surface of the thin film III-V compound solar cell before it is separated from the substrate. To separate the thin film III-V compound solar cell from the substrate, the sacrificial layer is removed as part of the epitaxial lift-off. Once the substrate is separated from the thin film III-V compound solar cell, the substrate may then be reused in the formation of another thin film III-V compound solar cell.

  19. Thin film cadmium telluride and zinc phosphide solar cells

    SciTech Connect (OSTI)

    Chu, T.

    1984-10-01

    This report describes research performed from June 1982 to October 1983 on the deposition of cadmium telluride films by direct combination of the cadmium and tellurium vapor on foreign substrates. Nearly stoichiometric p-type cadmium telluride films and arsenic-doped p-type films have been prepared reproducibly. Major efforts were directed to the deposition and characterization of heterojunction window materials, indium tin oxide, fluorine-doped tin oxide, cadmium oxide, and zinc oxide. A number of heterojunction solar cells were prepared, and the best thin-film ITO/CdTe solar cells had an AMl efficiency of about 7.2%. Zinc phosphide films were deposited on W/steel substrates by the reaction of zinc and phosphine in a hydrogen flow. Films without intentional doping had an electrical resistivity on the order of 10/sup 6/ ohm-cm, and this resistivity may be reduced to about 5 x 10/sup 4/ ohm-cm by adding hydrogen chloride or hydrogen bromide to the reaction mixture. Lower resistivity films were deposited by adding a controlled amount of silver nitrate solution on to the substrate surface. Major efforts were directed to the deposition of low-resistivity zinc selenide in order to prepare ZnSe/An/sub 3/P/sub 2/ heterojunction thin-film solar cells. However, zinc selenide films deposited by vacuum evaporation and chemical vapor deposition techniques were all of high resistivity.

  20. Solar Plus SA | Open Energy Information

    Open Energy Info (EERE)

    Plus SA Jump to: navigation, search Name: Solar Plus SA Place: Lisbon, Portugal Sector: Solar Product: Plans to set up a 5.5MWyear thin-film silicon module factory in Aveiro,...

  1. T Solar Global SA | Open Energy Information

    Open Energy Info (EERE)

    Solar Global SA Jump to: navigation, search Name: T-Solar Global SA Place: Madrid, Spain Zip: 28042 Product: Spain-based thin-film silicon PV cell and module maker, using Applied...

  2. Kaneka Solar Tech Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Tech Inc Jump to: navigation, search Name: Kaneka Solar-Tech Inc Place: Osaka, Japan Zip: 530-8288 Product: Manufactures thin-film amorphous silicon PV cells and modules....

  3. Amorphous silicon cell array powered solar tracking apparatus

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1985-01-01

    An array of an even number of amorphous silicon solar cells are serially connected between first and second terminals of opposite polarity. The terminals are connected to one input terminal of a DC motor whose other input terminal is connected to the mid-cell of the serial array. Vane elements are adjacent the end cells to selectively shadow one or the other of the end cells when the array is oriented from a desired attitude relative to the sun. The shadowing of one cell of a group of cells on one side of the mid-cell reduces the power of that group substantially so that full power from the group of cells on the other side of the mid-cell drives the motor to reorient the array to the desired attitude. The cell groups each have a full power output at the power rating of the motor. When the array is at the desired attitude the power output of the two groups of cells balances due to their opposite polarity so that the motor remains unpowered.

  4. See-through amorphous silicon solar cells with selectively transparent and conducting photonic crystal back reflectors for building integrated photovoltaics

    SciTech Connect (OSTI)

    Yang, Yang; OBrien, Paul G.; Materials Chemistry Research Group, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6 ; Ozin, Geoffrey A. E-mail: kherani@ecf.utoronto.ca; Kherani, Nazir P. E-mail: kherani@ecf.utoronto.ca

    2013-11-25

    Thin semi-transparent hydrogenated amorphous silicon (a-Si:H) solar cells with selectively transparent and conducting photonic crystal (STCPC) back-reflectors are demonstrated. Short circuit current density of a 135?nm thick a-Si:H cell with a given STCPC back-reflector is enhanced by as much as 23% in comparison to a reference cell with an ITO film functioning as its rear contact. Concurrently, solar irradiance of 295?W/m{sup 2} and illuminance of 3480 lux are transmitted through the cell with a given STCPC back reflector under AM1.5 Global tilt illumination, indicating its utility as a source of space heating and lighting, respectively, in building integrated photovoltaic applications.

  5. High Efficiency CdTe and CIGS Thin Film Solar Cells: Highlights...

    Office of Scientific and Technical Information (OSTI)

    High Efficiency CdTe and CIGS Thin Film Solar Cells: Highlights of the Technologies Challenges Acknowledgement: Work performed at NREL for US DOE under contract No....

  6. New Selection Metric for Design of Thin-Film Solar Cell Absorber...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    guidance for the experimental synthesis. New Selection Metric for Design of Thin-Film Solar Cell Absorber Materials Research Details * SLME account s for the physics of...

  7. High efficiency solar cells combining a perovskite and a silicon heterojunction solar cells via an optical splitting system

    SciTech Connect (OSTI)

    Uzu, Hisashi E-mail: npark@skku.edu; Ichikawa, Mitsuru; Hino, Masashi; Nakano, Kunihiro; Meguro, Tomomi; Yamamoto, Kenji; Hernndez, Jos Luis; Kim, Hui-Seon; Park, Nam-Gyu E-mail: npark@skku.edu

    2015-01-05

    We have applied an optical splitting system in order to achieve very high conversion efficiency for a full spectrum multi-junction solar cell. This system consists of multiple solar cells with different band gap optically coupled via an optical splitter. An optical splitter is a multi-layered beam splitter with very high reflection in the shorter-wave-length range and very high transmission in the longer-wave-length range. By splitting the incident solar spectrum and distributing it to each solar cell, the solar energy can be managed more efficiently. We have fabricated optical splitters and used them with a wide-gap amorphous silicon (a-Si) solar cell or a CH{sub 3}NH{sub 3}PbI{sub 3} perovskite solar cell as top cells, combined with mono-crystalline silicon heterojunction (HJ) solar cells as bottom cells. We have achieved with a 550?nm cutoff splitter an active area conversion efficiency of over 25% using a-Si and HJ solar cells and 28% using perovskite and HJ solar cells.

  8. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    work offers the first, thin, MEMS contact-stress (CS) sensor capable of accurate in situ measruement of time-varying, contact-stress between two solid interfaces (e.g. in vivo cartilage contact-stress and body armor dynamic loading). This CS sensor is a silicon-based device with a load sensitive diaphragm. The diaphragm is doped to create piezoresistors arranged in a full Wheatstone bridge. The sensor is similar in performance to established silicon pressure sensors, but it is reliably produced

  9. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    work offers the first, thin, MEMS contact-stress (CS) sensor capable of accurate in situ measruement of time-varying, contact-stress between two solid interfaces (e.g. in vivo cartilage contact-stress and body armor dynamic loading). This CS sensor is a silicon-based device with a load sensitive diaphragm. The diaphragm is doped to create piezoresistors arranged in a full Wheatstone bridge. The sensor is similar in performance to established silicon pressure sensors, but it is reliably produced

  10. Stable, high-efficiency amorphous silicon solar cells with low hydrogen content

    SciTech Connect (OSTI)

    Fortmann, C.M.; Hegedus, S.S. )

    1992-12-01

    Results and conclusions obtained during a research program of the investigation of amorphous silicon and amorphous silicon based alloy materials and solar cells fabricated by photo-chemical vapor and glow discharge depositions are reported. Investigation of the effects of the hydrogen content in a-si:H i-layers in amorphous silicon solar cells show that cells with lowered hydrogen content i-layers are more stable. A classical thermodynamic formulation of the Staebler-Wronski effect has been developed for standard solar cell operating temperatures and illuminations. Methods have been developed to extract a lumped equivalent circuit from the current voltage characteristic of a single junction solar cell in order to predict its behavior in a multijunction device.

  11. Junction Evolution During Fabrication of CdS/CdTe Thin-film PV Solar Cells (Presentation)

    SciTech Connect (OSTI)

    Gessert, T. A.

    2010-09-01

    Discussion of the formation of CdTe thin-film PV junctions and optimization of CdTe thin-film PV solar cells.

  12. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    thin, MEMS contact-stress (CS) sensor continuously and accurately measures time-varying, solid interface loads in embedded systems over tens of thousands of load cycles. Unlike all other interface load sensors, the CS sensor is extremely thin (< 150 {micro}m), provides accurate, high-speed measurements, and exhibits good stability over time with no loss of calibration with load cycling. The silicon CS sensor, 5 mm{sup 2} and 65 {micro}m thick, has piezoresistive traces doped within a

  13. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    thin, MEMS contact-stress (CS) sensor continuously and accurately measures time-varying, solid interface loads in embedded systems over tens of thousands of load cycles. Unlike all other interface load sensors, the CS sensor is extremely thin (< 150 {micro}m), provides accurate, high-speed measurements, and exhibits good stability over time with no loss of calibration with load cycling. The silicon CS sensor, 5 mm{sup 2} and 65 {micro}m thick, has piezoresistive traces doped within a

  14. California: TetraCell Silicon Solar Cell Improves Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    TetraSun, in partnership with the National Renewable Energy Laboratory, developed a novel crystalline silicon photovoltaic (PV) cell architecture and manufacturing process that ...

  15. Strongly enhanced tunable photoluminescence in polymorphous silicon carbon thin films via excitation-transfer mechanism

    SciTech Connect (OSTI)

    Wang Junzhuan; Suendo, V.; Abramov, A.; Yu Linwei; Roca i Cabarrocas, Pere

    2010-11-29

    Here, we investigate the enhanced tunable photoluminescence (PL) of hydrogenated polymorphous silicon carbon (pm-Si{sub 1-x}C{sub x}:H) thin films fabricated in a plasma enhanced chemical vapor deposition system. The silicon nanocrystal (nc-Si) inclusions are formed during gas-phase nucleation and incorporated in the hydrogenated amorphous silicon carbon (a-SiC:H) matrix. The nc-Si provides high-quality recombination centers for the photogenerated carriers in the pm-Si{sub 1-x}C{sub x}:H material, while the a-SiC:H matrix plays a role of sensitizer. We elucidate and provide experimental evidence for this excitation-transfer mechanism. Strongly enhanced PL performance can be achieved by effective matrix passivation that favors a diffusion-driven carrier recombination in the nc-Si centers.

  16. Method of fabrication of display pixels driven by silicon thin film transistors

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA)

    1999-01-01

    Display pixels driven by silicon thin film transistors are fabricated on plastic substrates for use in active matrix displays, such as flat panel displays. The process for forming the pixels involves a prior method for forming individual silicon thin film transistors on low-temperature plastic substrates. Low-temperature substrates are generally considered as being incapable of withstanding sustained processing temperatures greater than about 200.degree. C. The pixel formation process results in a complete pixel and active matrix pixel array. A pixel (or picture element) in an active matrix display consists of a silicon thin film transistor (TFT) and a large electrode, which may control a liquid crystal light valve, an emissive material (such as a light emitting diode or LED), or some other light emitting or attenuating material. The pixels can be connected in arrays wherein rows of pixels contain common gate electrodes and columns of pixels contain common drain electrodes. The source electrode of each pixel TFT is connected to its pixel electrode, and is electrically isolated from every other circuit element in the pixel array.

  17. Method for fabricating pixelated silicon device cells

    DOE Patents [OSTI]

    Nielson, Gregory N.; Okandan, Murat; Cruz-Campa, Jose Luis; Nelson, Jeffrey S.; Anderson, Benjamin John

    2015-08-18

    A method, apparatus and system for flexible, ultra-thin, and high efficiency pixelated silicon or other semiconductor photovoltaic solar cell array fabrication is disclosed. A structure and method of creation for a pixelated silicon or other semiconductor photovoltaic solar cell array with interconnects is described using a manufacturing method that is simplified compared to previous versions of pixelated silicon photovoltaic cells that require more microfabrication steps.

  18. Microstructure factor and mechanical and electronic properties of hydrogenated amorphous and nanocrystalline silicon thin-films for microelectromechanical systems applications

    SciTech Connect (OSTI)

    Mouro, J.; Gualdino, A.; Chu, V. [Instituto de Engenharia de Sistemas e Computadores Microsistemas e Nanotecnologias (INESC-MN) and IN Institute of Nanoscience and Nanotechnology, 1000-029 Lisbon (Portugal); Conde, J. P. [Instituto de Engenharia de Sistemas e Computadores Microsistemas e Nanotecnologias (INESC-MN) and IN Institute of Nanoscience and Nanotechnology, 1000-029 Lisbon (Portugal); Department of Bioengineering, Instituto Superior Tcnico (IST), 1049-001 Lisbon (Portugal)

    2013-11-14

    Thin-film silicon allows the fabrication of MEMS devices at low processing temperatures, compatible with monolithic integration in advanced electronic circuits, on large-area, low-cost, and flexible substrates. The most relevant thin-film properties for applications as MEMS structural layers are the deposition rate, electrical conductivity, and mechanical stress. In this work, n{sup +}-type doped hydrogenated amorphous and nanocrystalline silicon thin-films were deposited by RF-PECVD, and the influence of the hydrogen dilution in the reactive mixture, the RF-power coupled to the plasma, the substrate temperature, and the deposition pressure on the structural, electrical, and mechanical properties of the films was studied. Three different types of silicon films were identified, corresponding to three internal structures: (i) porous amorphous silicon, deposited at high rates and presenting tensile mechanical stress and low electrical conductivity, (ii) dense amorphous silicon, deposited at intermediate rates and presenting compressive mechanical stress and higher values of electrical conductivity, and (iii) nanocrystalline silicon, deposited at very low rates and presenting the highest compressive mechanical stress and electrical conductivity. These results show the combinations of electromechanical material properties available in silicon thin-films and thus allow the optimized selection of a thin silicon film for a given MEMS application. Four representative silicon thin-films were chosen to be used as structural material of electrostatically actuated MEMS microresonators fabricated by surface micromachining. The effect of the mechanical stress of the structural layer was observed to have a great impact on the device resonance frequency, quality factor, and actuation force.

  19. NREL and Company Researchers Team Up on Thin-Film Solar Cells - News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Releases | NREL NREL and Company Researchers Team Up on Thin-Film Solar Cells November 12, 2003 Golden, Colo. - An Austin, Tex.-based company is moving toward commercial production of advanced solar cells by using unique facilities and capabilities of the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL). HelioVolt Corp. is attempting to prove the viability of patented technology it has developed for making thin-film Copper Indium Gallium Diselenide (CIGS) solar

  20. Fundamental understanding and development of low-cost, high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    ROHATGI,A.; NARASIMHA,S.; MOSCHER,J.; EBONG,A.; KAMRA,S.; KRYGOWSKI,T.; DOSHI,P.; RISTOW,A.; YELUNDUR,V.; RUBY,DOUGLAS S.

    2000-05-01

    The overall objectives of this program are (1) to develop rapid and low-cost processes for manufacturing that can improve yield, throughput, and performance of silicon photovoltaic devices, (2) to design and fabricate high-efficiency solar cells on promising low-cost materials, and (3) to improve the fundamental understanding of advanced photovoltaic devices. Several rapid and potentially low-cost technologies are described in this report that were developed and applied toward the fabrication of high-efficiency silicon solar cells.

  1. Foaming of aluminium-silicon alloy using concentrated solar energy

    SciTech Connect (OSTI)

    Cambronero, L.E.G.; Ruiz-Roman, J.M.; Canadas, I.; Martinez, D.

    2010-06-15

    Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close to 300 W/cm{sup 2} on the mould is high enough to achieve complete foaming after heating for only 200 s. Under these conditions, the density and pore distribution in the foam change depending on the solar heating parameters and mould design. (author)

  2. Rapid Deposition Technology Holds the Key for the World's Largest Manufacturer of Thin-Film Solar Modules (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-08-01

    First Solar, Inc. has been collaborating with NREL since 1991, advancing its thin-film cadmium telluride solar technology to grow from a startup company to become one of the world's largest manufacturers of solar modules, and the world's largest manufacturer of thin-film solar modules.

  3. Sequential lateral solidification of silicon thin films on low-k dielectrics for low temperature integration

    SciTech Connect (OSTI)

    Carta, Fabio Hlaing, Htay; Kymissis, Ioannis; Gates, Stephen M.; Edelstein, Daniel C.; Limanov, Alexander B.; Im, James S.

    2014-12-15

    We present the excimer laser crystallization of amorphous silicon on a low dielectric constant (low-k) insulator for very large scale integration monolithic 3D integration and demonstrate that low dielectric constant materials are suitable substrates for 3D integration through laser crystallization of silicon thin films. We crystallized 100?nm amorphous silicon on top of SiO{sub 2} and SiCOH (low-k) dielectrics, at different material thicknesses (1??m, 0.75??m, and 0.5??m). The amorphous silicon crystallization on low-k dielectric requires 35% less laser energy than on an SiO{sub 2} dielectric. This difference is related to the thermal conductivity of the two materials, in agreement with one dimensional simulations of the crystallization process. We analyzed the morphology of the material through defect-enhanced microscopy, Raman spectroscopy, and X-ray diffraction analysis. SEM micrographs show that polycrystalline silicon is characterized by micron-long grains with an average width of 543?nm for the SiO{sub 2} sample and 570?nm for the low-k samples. Comparison of the Raman spectra does not show any major difference in film quality for the two different dielectrics, and polycrystalline silicon peaks are closely placed around 517?cm{sup ?1}. From X-ray diffraction analysis, the material crystallized on SiO{sub 2} shows a preferential (111) crystal orientation. In the SiCOH case, the 111 peak strength decreases dramatically and samples do not show preferential crystal orientation. A 1D finite element method simulation of the crystallization process on a back end of line structure shows that copper (Cu) damascene interconnects reach a temperature of 70?C or lower with a 0.5??m dielectric layer between the Cu and the molten Si layer, a favorable condition for monolithic 3D integration.

  4. Gadir Solar | Open Energy Information

    Open Energy Info (EERE)

    Name: Gadir Solar Place: Madrid, Spain Zip: 28001 Product: Madrid-based manufacturer of thin-film silicon PV modules. Coordinates: 40.4203, -3.705774 Show Map Loading map......

  5. Development of Novel Front Contract Pastes for Crystalline Silicon Solar Cells

    SciTech Connect (OSTI)

    Duty, C.; Jellison, D. G.E. P.; Joshi, P.

    2012-04-05

    In order to improve the efficiencies of silicon solar cells, paste to silicon contact formation mechanisms must be more thoroughly understood as a function of paste chemistry, wafer properties and firing conditions. Ferro Corporation has been involved in paste development for over 30 years and has extensive expertise in glass and paste formulations. This project has focused on the characterization of the interface between the top contact material (silver paste) and the underlying silicon wafer. It is believed that the interface between the front contact silver and the silicon wafer plays a dominant role in the electrical performance of the solar cell. Development of an improved front contact microstructure depends on the paste chemistry, paste interaction with the SiNx, and silicon (Si) substrate, silicon sheet resistivity, and the firing profile. Typical front contact ink contains silver metal powders and flakes, glass powder and other inorganic additives suspended in an organic medium of resin and solvent. During fast firing cycles glass melts, wets, corrodes the SiNx layer, and then interacts with underlying Si. Glass chemistry is also a critical factor in the development of an optimum front contact microstructure. Over the course of this project, several fundamental characteristics of the Ag/Si interface were documented, including a higher-than-expected distribution of voids along the interface, which could significantly impact electrical conductivity. Several techniques were also investigated for the interfacial analysis, including STEM, EDS, FIB, EBSD, and ellipsometry.

  6. Fabrication of back-contacted silicon solar cells using thermomigration to create conductive vias

    DOE Patents [OSTI]

    Gee, James M; Schmit, Russell R.

    2007-01-30

    Methods of manufacturing back-contacted silicon solar cells fabricated using a gradient-driven solute transport process, such as thermomigration or electromigration, to create n-type conductive vias connecting the n-type emitter layer on the front side to n-type ohmic contacts located on the back side.

  7. Liquid-phase-deposited siloxane-based capping layers for silicon solar cells

    SciTech Connect (OSTI)

    Veith-Wolf, Boris; Wang, Jianhui; Hannu-Kuure, Milja; Chen, Ning; Hadzic, Admir; Williams, Paul; Leivo, Jarkko; Karkkainen, Ari; Schmidt, Jan

    2015-02-02

    We apply non-vacuum processing to deposit dielectric capping layers on top of ultrathin atomic-layer-deposited aluminum oxide (AlO{sub x}) films, used for the rear surface passivation of high-efficiency crystalline silicon solar cells. We examine various siloxane-based liquid-phase-deposited (LPD) materials. Our optimized AlO{sub x}/LPD stacks show an excellent thermal and chemical stability against aluminum metal paste, as demonstrated by measured surface recombination velocities below 10 cm/s on 1.3 Ωcm p-type silicon wafers after firing in a belt-line furnace with screen-printed aluminum paste on top. Implementation of the optimized LPD layers into an industrial-type screen-printing solar cell process results in energy conversion efficiencies of up to 19.8% on p-type Czochralski silicon.

  8. Amorphous/crystalline silicon interface passivation: Ambient-temperature dependence and implications for solar cell performance

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Seif, Johannes P.; Krishnamani, Gopal; Demaurex, Benedicte; Ballif, Christophe; Wolf, Stefaan De

    2015-03-02

    Silicon heterojunction (SHJ) solar cells feature amorphous silicon passivation films, which enable very high voltages. We report how such passivation increases with operating temperature for amorphous silicon stacks involving doped layers and decreases for intrinsic-layer-only passivation. We discuss the implications of this phenomenon on the solar cell's temperature coefficient, which represents an important figure-of-merit for the energy yield of devices deployed in the field. We show evidence that both open-circuit voltage (Voc) and fill factor (FF) are affected by these variations in passivation and quantify these temperature-mediated effects, compared with those expected from standard diode equations. We confirm that devicesmore » with high Voc values at 25°C show better high-temperature performance. Thus, we also argue that the precise device architecture, such as the presence of charge-transport barriers, may affect the temperature-dependent device performance as well.« less

  9. Amorphous/crystalline silicon interface passivation: Ambient-temperature dependence and implications for solar cell performance

    SciTech Connect (OSTI)

    Seif, Johannes P.; Krishnamani, Gopal; Demaurex, Benedicte; Ballif, Christophe; Wolf, Stefaan De

    2015-03-02

    Silicon heterojunction (SHJ) solar cells feature amorphous silicon passivation films, which enable very high voltages. We report how such passivation increases with operating temperature for amorphous silicon stacks involving doped layers and decreases for intrinsic-layer-only passivation. We discuss the implications of this phenomenon on the solar cell's temperature coefficient, which represents an important figure-of-merit for the energy yield of devices deployed in the field. We show evidence that both open-circuit voltage (Voc) and fill factor (FF) are affected by these variations in passivation and quantify these temperature-mediated effects, compared with those expected from standard diode equations. We confirm that devices with high Voc values at 25C show better high-temperature performance. Thus, we also argue that the precise device architecture, such as the presence of charge-transport barriers, may affect the temperature-dependent device performance as well.

  10. Molecular dynamics simulations of grain boundaries in thin nanocrystalline silicon films

    SciTech Connect (OSTI)

    Berman, G.P.; Doolen, G.D.; Mainieri, R.; Campbell, D.K.; Luchnikov, V.A. |

    1997-10-01

    Using molecular dynamics simulations, the grain boundaries in thin polycrystalline silicon films (considered as promising material for future nanoelectronic devices) are investigated. It is shown that in polysilicon film with randomly oriented grains the majority of grain boundaries are disordered. However, some grains with small mutual orientation differences can form extended crystalline patterns. The structure of the grain boundaries satisfies the thermodynamical criterion. The majority of atoms in the grain boundaries are tetrahedrally coordinated with the nearest neighbors, even though the grain boundaries are disordered. The grain boundary matter is characterized as an amorphous phase with a characteristic tetragonality value.

  11. New GE Plant to Produce Thin Film PV Solar Panels Based on NREL Technology

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy GE Plant to Produce Thin Film PV Solar Panels Based on NREL Technology New GE Plant to Produce Thin Film PV Solar Panels Based on NREL Technology April 22, 2011 - 10:17am Addthis Photo courtesy of General Electric Photo courtesy of General Electric Minh Le Minh Le Director, Solar Energy Technologies Office Earlier this month, General Electric announced plans to enter the global marketplace for solar photovoltaic (PV) panels in a big way - and to do it, they will be

  12. Near-field radiative heat transfer between metamaterials coated with silicon carbide thin films

    SciTech Connect (OSTI)

    Basu, Soumyadipta Yang, Yue; Wang, Liping

    2015-01-19

    In this letter, we study the near-field radiative heat transfer between two metamaterial substrates coated with silicon carbide (SiC) thin films. It is known that metamaterials can enhance the near-field heat transfer over ordinary materials due to excitation of magnetic plasmons associated with s polarization, while strong surface phonon polariton exists for SiC. By careful tuning of the optical properties of metamaterial, it is possible to excite electrical and magnetic resonances for the metamaterial and surface phonon polaritons for SiC at different spectral regions, resulting in the enhanced heat transfer. The effect of the SiC film thickness at different vacuum gaps is investigated. Results obtained from this study will be beneficial for application of thin film coatings for energy harvesting.

  13. Efficiency calculations of thin-film GaAs solar cells on Si substrates

    SciTech Connect (OSTI)

    Yamaguchi, M.; Amano, C.

    1985-11-01

    Dislocation effect upon the efficiency of single-crystal thin-film AlGaAs-GaAs heteroface solar cells on Si substrates is analyzed. Solar-cell properties are calculated based on a simple model; in the model, dislocations act as recombination centers to reduce the minority-carrier diffusion length in each layer and increase the space-charge layer recombination current. Numerical analysis is also carried out to optimize thin-film AlGaAs-GaAs heteroface solar-cell structures. The fabrication of thin-film AlGaAs-GaAs heteroface solar cells with a practical efficiency larger than 18% on Si substrates appears possible if the dislocation density in the thin-film GaAs layer is less than 10/sup 6/ cm/sup -2/.

  14. Thin film GaAs solar cells on glass substrates by epitaxial liftoff

    SciTech Connect (OSTI)

    Lee, X.Y.; Goertemiller, M.; Boroditsky, M.; Ragan, R.; Yablonovitch, E.

    1997-02-01

    In this work, we describe the fabrication and operating characteristics of GaAs/AlGaAs thin film solar cells processed by the epitaxial liftoff (ELO) technique. This technique allows the transfer of these cells onto glass substrates. The performance of the lifted-off solar cell is demonstrated by means of electrical measurements under both dark and illuminated conditions. We have also optimized the light trapping conditions in this direct-gap material. The results show that good solar absorption is possible in active layers as thin as 0.32 {mu}m. In such a thin solar cell, the open circuit voltage would be enhanced. We believe that the combination of an epitaxial liftoff thin GaAs film, and nano-texturing can lead to record breaking performance. {copyright} {ital 1997 American Institute of Physics.}

  15. Thin polymer film collectors as a contribution to the solar industry

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1984-06-01

    Achievements made in research on thin polymer film solar flat-plate collectors using monocoque construction techniques are briefly discussed. The significance of these achievements for cost reduction of flat-plate collectors without compromising performance is briefly discussed.

  16. Optically activated sub-millimeter dielectric relaxation in amorphous thin film silicon at room temperature

    SciTech Connect (OSTI)

    Rahman, Rezwanur; Ohno, Tim R.; Taylor, P. C.; Scales, John A.

    2014-05-05

    Knowing the frequency-dependent photo-induced complex conductivity of thin films is useful in the design of photovoltaics and other semi-conductor devices. For example, annealing in the far-infrared could in principle be tailored to the specific dielectric properties of a particular sample. The frequency dependence of the conductivity (whether dark or photo-induced) also gives insight into the effective dimensionality of thin films (via the phonon density of states) as well as the presence (or absence) of free carriers, dopants, defects, etc. Ultimately, our goal is to make low-noise, phase-sensitive room temperature measurements of the frequency-dependent conductivity of thin films from microwave frequencies into the far-infrared; covering, the frequency range from ionic and dipole relaxation to atomic and electronic processes. To this end, we have developed a high-Q (quality factor) open cavity resonator capable of resolving the complex conductivity of sub-micron films in the range of 100350?GHz (0.10.35 THz, or 0.41?meV). In this paper, we use a low-power green laser to excite bound charges in high-resistivity amorphous silicon thin film. Even at room temperature, we can resolve both the dark conductivity and photo-induced changes associated with dielectric relaxation and possibly some small portion of free carriers.

  17. High-Intensity Silicon Vertical Multi-Junction Solar Cells |...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Versatility Can be used in ground-mounted and roof-mounted deployments. Contact Information Mico Perales (216) 535-9200 mico.perales@greenfieldsolar.com GreenField Solar ...

  18. Silicon Ink Technology Offers Path to Higher Efficiency Solar...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Since 2007, EERE's SunShot Incubator program has invested 92 million in 54 solar startups that have attracted more than 1.7 billion in venture capital and private equity ...

  19. High-Efficiency Amorphous Silicon Alloy Based Solar Cells and Modules; Final Technical Progress Report, 30 May 2002--31 May 2005

    SciTech Connect (OSTI)

    Guha, S.; Yang, J.

    2005-10-01

    The principal objective of this R&D program is to expand, enhance, and accelerate knowledge and capabilities for development of high-efficiency hydrogenated amorphous silicon (a-Si:H) and amorphous silicon-germanium alloy (a-SiGe:H) related thin-film multijunction solar cells and modules with low manufacturing cost and high reliability. Our strategy has been to use the spectrum-splitting triple-junction structure, a-Si:H/a-SiGe:H/a-SiGe:H, to improve solar cell and module efficiency, stability, and throughput of production. The methodology used to achieve the objectives included: (1) explore the highest stable efficiency using the triple-junction structure deposited using RF glow discharge at a low rate, (2) fabricate the devices at a high deposition rate for high throughput and low cost, and (3) develop an optimized recipe using the R&D batch large-area reactor to help the design and optimization of the roll-to-roll production machines. For short-term goals, we have worked on the improvement of a-Si:H and a-SiGe:H alloy solar cells. a-Si:H and a-SiGe:H are the foundation of current a-Si:H based thin-film photovoltaic technology. Any improvement in cell efficiency, throughput, and cost reduction will immediately improve operation efficiency of our manufacturing plant, allowing us to further expand our production capacity.

  20. In-Line Crack and Stress Detection in Silicon Solar Cells Using Resonance Ultrasonic Vibrations

    SciTech Connect (OSTI)

    Ostapenko, Sergei

    2013-04-03

    Statement of Problem and Objectives. Wafer breakage in automated solar cell production lines is identified as a major technical problem and a barrier for further cost reduction of silicon solar module manufacturing. To the best of our knowledge, there are no commercial systems addressing critical needs for in-line inspection of the mechanical quality of solar wafers and cells. The principal objective of the SBIR program is to validate through experiments and computer modeling the applicability of the Resonance Ultrasonic Vibrations system, which ultimately can be used as a real-time in-line manufacturing quality control tool for fast detection of mechanically unstable silicon solar cells caused by cracks. The specific objective of Phase II is to move the technology of in-line crack detection from the laboratory level to commercial demonstration through development of a system prototype. The fragility of silicon wafers possessing low mechanical strength is attributed to peripheral and bulk millimeter-length cracks. The research program is based on feasibility results obtained during Phase I, which established that: (i) the Resonance Ultrasonic Vibrations method is applicable to as-cut, processed wafers and finished cells; (ii) the method sensitivity depends on the specific processing step; it is highest in as-cut wafers and lowest in wafers with metallization pattern and grid contacts; (iii) the system is capable of matching the 2.0 seconds per wafer throughput rate of state-of-art solar cell production lines; (iv) finite element modeling provides vibration mode analysis along with peak shift versus crack length and crack location dependence; (v) a high 91% crack rejection rate was confirmed through experimentation and statistical analysis. The Phase II project has the following specific tasks: (i) specify optimal configurations of the in-line system?¢????s component hardware and software; (ii) develop and justify a system prototype that meets major specifications for an in-line crack detection unit, such as high throughput rate, high level of stability, reproducibility of data acquisition and analysis, and high sensitivity with respect to crack length and crack location; (iii) design a system platform that allows easy integration within and adaptation to various solar cell belt-type production lines; (iv) develop a testing protocol providing quality certification of the production-grade system. Commercial Application of the proposed activity consists of bringing to the solar market a new high-tech product based on an innovative solution and patented methodology to contribute to cost reduction of silicon solar module production. The solar industry, with crystalline silicon as a dominant segment, shows outstanding performance, with approximately 25% yearly growth during the last years. Despite a slowdown with only 5.6 GW installations in 2009, solar module production for the 2010 and 2011 years was recovered. According to European Photonics Industry Consortium new solar PV installations grow by 56% compared to 2010 reached 64.7 GW in 2011. Revenues in the PV industry reached a record high of $93 billion in 2011, a 13.4 percent gain over 2010 â?? and 150 percent over 2009. This growth was forecasted to continue in 2013 with double digits growth. The solar industry is economically driven to make solar panels of the highest conversion efficiency and reliability at the lowest production cost. The Resonance Ultrasonic Vibration system addresses critical needs of the silicon-based solar industry by providing a quality control method and tool, which will improve productivity, increase reliability of products and reduce manufacturing cost of solar panels.

  1. Microscopic silicon-based lateral high-aspect-ratio structures for thin film conformality analysis

    SciTech Connect (OSTI)

    Gao, Feng; Arpiainen, Sanna; Puurunen, Riikka L.

    2015-01-15

    Film conformality is one of the major drivers for the interest in atomic layer deposition (ALD) processes. This work presents new silicon-based microscopic lateral high-aspect-ratio (LHAR) test structures for the analysis of the conformality of thin films deposited by ALD and by other chemical vapor deposition means. The microscopic LHAR structures consist of a lateral cavity inside silicon with a roof supported by pillars. The cavity length (e.g., 205000??m) and cavity height (e.g., 2001000?nm) can be varied, giving aspect ratios of, e.g., 20:1 to 25?000:1. Film conformality can be analyzed with the microscopic LHAR by several means, as demonstrated for the ALD Al{sub 2}O{sub 3} and TiO{sub 2} processes from Me{sub 3}Al/H{sub 2}O and TiCl{sub 4}/H{sub 2}O. The microscopic LHAR test structures introduced in this work expose a new parameter space for thin film conformality investigations expected to prove useful in the development, tuning and modeling of ALD and other chemical vapor deposition processes.

  2. Process and apparatus for casting multiple silicon wafer articles

    DOE Patents [OSTI]

    Nanis, Leonard (Palo Alto, CA)

    1992-05-05

    Method and apparatus of casting silicon produced by the reaction between SiF.sub.4 and an alkaline earth metal into thin wafer-shaped articles suitable for solar cell fabrication.

  3. 14th Workshop on Crystalline Silicon Solar Cells& Modules: Materials and Processes; Summary of Discussion Sessions

    SciTech Connect (OSTI)

    Sopori, B.; Tan, T.; Sinton, R.; Swanson, D.

    2004-10-01

    The 14th Workshop discussion sessions addressed funding needs for Si research and for R&D to enhance U.S. PV manufacturing. The wrap-up session specifically addressed topics for the new university silicon program. The theme of the workshop, Crystalline Silicon Solar Cells: Leapfrogging the Barriers, was selected to reflect the astounding progress in Si PV technology during last three decades, despite a host of barriers and bottlenecks. A combination of oral, poster, and discussion sessions addressed recent advances in crystal growth technology, new cell structures and doping methods, silicon feedstock issues, hydrogen passivation and fire through metallization, and module issues/reliability. The following oral/discussion sessions were conducted: (1) Technology Update; (2) Defects and Impurities in Si/Discussion; (3) Rump Session; (4) Module Issues and Reliability/Discussion; (5) Silicon Feedstock/Discussion; (6) Novel Doping, Cells, and Hetero-Structure Designs/Discussion; (7) Metallization/Silicon Nitride Processing/Discussion; (8) Hydrogen Passivation/Discussion; (9) Characterization/Discussion; and (10) Wrap-Up. This year's workshop lasted three and a half days and, for the first time, included a session on Si modules. A rump session was held on the evening of August 8, which addressed efficiency expectations and challenges of c Si solar cells/modules. Richard King of DOE and Daren Dance of Wright Williams& Kelly (formerly of Sematech) spoke at two of the luncheon sessions. Eleven students received Graduate Student Awards from funds contributed by the PV industry.

  4. Epitaxial Crystal Silicon Absorber Layers and Solar Cells Grown at 1.8 Microns per Minute: Preprint

    SciTech Connect (OSTI)

    Bobela, D. C.; Teplin, C. W.; Young, D. L.; Branz, H. M.; Stradins, P.

    2011-07-01

    We have grown device-quality epitaxial silicon thin films at growth rates up to 1.8 ?m/min, using hot-wire chemical vapor deposition from silane at substrate temperatures below 750 degrees C. At these rates, which are more than 30 times faster than those used by the amorphous and nanocrystalline Si industry, capital costs for large-scale solar cell production would be dramatically reduced, even for cell absorber layers up to 10 ?m thick. We achieved high growth rates by optimizing the three key parameters: silane flow, depletion, and filament geometry, based on our model developed earlier. Hydrogen coverage of the filament surface likely limits silane decomposition and growth rate at high system pressures. No considerable deterioration in PV device performance is observed when grown at high rate, provided that the epitaxial growth is initiated at low rate. A simple mesa device structure (wafer/epi Si/a-Si(i)/a-Si:H(p)/ITO) with a 2.3 um epitaxial silicon absorber layer was grown at 700 nm/min. The finished device had an open-circuit voltage of 0.424 V without hydrogenation treatment.

  5. NREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-09-01

    Researchers at the National Renewable Energy Laboratory (NREL) are finding new ways to manufacture thin-film solar cells made from copper, indium, gallium, and selenium - called CIGS cells - that are different than conventional CIGS solar cells. Their use of high-temperature glass, designed by SCHOTT AG, allows higher fabrication temperatures, opening the door to new CIGS solar cells employing light-absorbing materials with wide 'bandgaps.'

  6. Plasma etching, texturing, and passivation of silicon solar cells

    SciTech Connect (OSTI)

    Ruby, D.S.; Yang, P.; Zaidi, S.; Brueck, S.; Roy, M.; Narayanan, S.

    1998-11-01

    The authors improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. The authors used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. They obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. They also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion.

  7. Plasma etching, texturing, and passivation of silicon solar cells

    SciTech Connect (OSTI)

    Ruby, D.S.; Yang, P.; Brueck, S.; Narayanan, S.

    1999-03-01

    We improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. We used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. We obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. We also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion. {copyright} {ital 1999 American Institute of Physics.}

  8. Plasma texturing, etching and passivation of multicrystalline silicon solar cells

    SciTech Connect (OSTI)

    Ruby, D.S.; Yang, P.; Zaidi, S.; Roy, M.; Narayanan, S.

    1999-07-01

    The authors improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. The authors used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. They obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. They also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion.

  9. Semi-transparent perovskite solar cells for tandems with silicon and CIGS

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bailie, Colin D.; Christoforo, M. Greyson; Mailoa, Jonathan P.; Bowring, Andrea R.; Unger, Eva L.; Nguyen, William H.; Burschka, Julian; Pellet, Norman; Lee, Jungwoo Z.; Grätzel, Michael; et al

    2014-12-23

    A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. Furthermore, this work paves the way for integrating perovskites into a low-costmore » and high-efficiency (>25%) tandem cell.« less

  10. Semi-transparent perovskite solar cells for tandems with silicon and CIGS

    SciTech Connect (OSTI)

    Bailie, Colin D.; Christoforo, M. Greyson; Mailoa, Jonathan P.; Bowring, Andrea R.; Unger, Eva L.; Nguyen, William H.; Burschka, Julian; Pellet, Norman; Lee, Jungwoo Z.; Grtzel, Michael; Noufi, Rommel; Buonassisi, Tonio; Salleo, Alberto; McGehee, Michael D.

    2014-12-23

    A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. Furthermore, this work paves the way for integrating perovskites into a low-cost and high-efficiency (>25%) tandem cell.

  11. Efficiency considerations for polycrystalline GaAs thin-film solar cells

    SciTech Connect (OSTI)

    Yamaguchi, M.; Itoh, Y.

    1986-07-01

    The effect of grain boundaries upon the efficiency of polycrystalline GaAs thin-film solar cells is analyzed. Solar-cell properties are calculated on a simple model where grain boundaries act as recombination centers to reduce the minority-carrier diffusion length in the solar cell's active layer and increase the space-charge layer recombination current. An effective diffusion length is expressed in terms of grain size, allowing the calculation of short-circuit current density and open-circuit voltage. Excellent agreement is obtained between theory and experiment. The fabrication of thin-film GaAs solar cells with an efficiency greater than 18% appears to be possible if the grain size in the thin-film GaAs layer with thickness of 3 ..mu..m is larger than 1000 ..mu..m.

  12. Multi-Layer Inkjet Printed Contacts for Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Curtis, C. J.; van hest, M.; Miedaner, A.; Kaydanova, T.; Smith, L.; Ginley, D. S.

    2006-05-01

    Ag, Cu, and Ni metallizations were inkjet printed with near vacuum deposition quality. The approach developed can be easily extended to other conductors such as Pt, Pd, Au, etc. Thick highly conducting lines of Ag and Cu demonstrating good adhesion to glass, Si, and printed circuit board (PCB) have been printed at 100-200 C in air and N2 respectively. Ag grids were inkjet-printed on Si solar cells and fired through the silicon nitride AR layer at 850 C, resulting in 8% cells. Next generation inks, including an ink that etches silicon nitride, have now been developed. Multi-layer inkjet printing of the etching ink followed by Ag ink produced contacts under milder conditions and gave solar cells with efficiencies as high as 12%.

  13. Eighth Workshop on Crystalline Silicon Solar Cell Materials and Processes; Summary Discussion Sessions

    SciTech Connect (OSTI)

    Sopori, B.; Swanson, D.; Sinton, R.; Stavola, M.; Tan, T.

    1998-12-08

    This report is a summary of the panel discussions included with the Eighth Workshop on Crystalline Silicon Solar Cell Materials and Processes. The theme of the workshop was ''Supporting the Transition to World Class Manufacturing.'' This workshop provided a forum for an informal exchange of information between researchers in the photovoltaic and nonphotovoltaic fields on various aspects of impurities and defects in silicon, their dynamics during device processing, and their application in defect engineering. This interaction helped establish a knowledge base that can be used for improving device-fabrication processes to enhance solar-cell performance and reduce cell costs. It also provided an excellent opportunity for researchers from industry and universities to recognize mutual needs for future joint research.

  14. Solar cells utilizing pulsed-energy crystallized microcrystalline/polycrystalline silicon

    DOE Patents [OSTI]

    Kaschmitter, J.L.; Sigmon, T.W.

    1995-10-10

    A process for producing multi-terminal devices such as solar cells wherein a pulsed high energy source is used to melt and crystallize amorphous silicon deposited on a substrate which is intolerant to high processing temperatures, whereby the amorphous silicon is converted into a microcrystalline/polycrystalline phase. Dopant and hydrogenation can be added during the fabrication process which provides for fabrication of extremely planar, ultra shallow contacts which results in reduction of non-current collecting contact volume. The use of the pulsed energy beams results in the ability to fabricate high efficiency microcrystalline/polycrystalline solar cells on the so-called low-temperature, inexpensive plastic substrates which are intolerant to high processing temperatures.

  15. Solar cells utilizing pulsed-energy crystallized microcrystalline/polycrystalline silicon

    DOE Patents [OSTI]

    Kaschmitter, James L. (Pleasanton, CA); Sigmon, Thomas W. (Beaverton, OR)

    1995-01-01

    A process for producing multi-terminal devices such as solar cells wherein a pulsed high energy source is used to melt and crystallize amorphous silicon deposited on a substrate which is intolerant to high processing temperatures, whereby to amorphous silicon is converted into a microcrystalline/polycrystalline phase. Dopant and hydrogenization can be added during the fabrication process which provides for fabrication of extremely planar, ultra shallow contacts which results in reduction of non-current collecting contact volume. The use of the pulsed energy beams results in the ability to fabricate high efficiency microcrystalline/polycrystalline solar cells on the so-called low-temperature, inexpensive plastic substrates which are intolerant to high processing temperatures.

  16. Silicon solar cells made by a self-aligned, selective-emitter, plasma-etchback process

    DOE Patents [OSTI]

    Ruby, Douglas S. (Albuquerque, NM); Schubert, William K. (Albuquerque, NM); Gee, James M. (Albuquerque, NM)

    1999-01-01

    A potentially low-cost process for forming and passivating a selective emitter. The process uses a plasma etch of the heavily doped emitter to improve its performance. The grids of the solar cell are used to mask the plasma etch so that only the emitter in the region between the grids is etched, while the region beneath the grids remains heavily doped for low contact resistance. This process is potentially low-cost because it requires no alignment. After the emitter etch, a silicon nitride layer is deposited by plasma-enhanced, chemical vapor deposition, and the solar cell is annealed in a forming gas.

  17. Silicon solar cells made by a self-aligned, selective-emitter, plasma-etchback process

    DOE Patents [OSTI]

    Ruby, D.S.; Schubert, W.K.; Gee, J.M.

    1999-02-16

    A potentially low-cost process for forming and passivating a selective emitter. The process uses a plasma etch of the heavily doped emitter to improve its performance. The grids of the solar cell are used to mask the plasma etch so that only the emitter in the region between the grids is etched, while the region beneath the grids remains heavily doped for low contact resistance. This process is potentially low-cost because it requires no alignment. After the emitter etch, a silicon nitride layer is deposited by plasma-enhanced, chemical vapor deposition, and the solar cell is annealed in a forming gas. 5 figs.

  18. Optimization of oxidation processes to improve crystalline silicon solar cell emitters

    SciTech Connect (OSTI)

    Shen, L.; Liang, Z. C. Liu, C. F.; Long, T. J.; Wang, D. L.

    2014-02-15

    Control of the oxidation process is one key issue in producing high-quality emitters for crystalline silicon solar cells. In this paper, the oxidation parameters of pre-oxidation time, oxygen concentration during pre-oxidation and pre-deposition and drive-in time were optimized by using orthogonal experiments. By analyzing experimental measurements of short-circuit current, open circuit voltage, series resistance and solar cell efficiency in solar cells with different sheet resistances which were produced by using different diffusion processes, we inferred that an emitter with a sheet resistance of approximately 70 ?/? performed best under the existing standard solar cell process. Further investigations were conducted on emitters with sheet resistances of approximately 70 ?/? that were obtained from different preparation processes. The results indicate that emitters with surface phosphorus concentrations between 4.96 10{sup 20} cm{sup ?3} and 7.78 10{sup 20} cm{sup ?3} and with junction depths between 0.46 ?m and 0.55 ?m possessed the best quality. With no extra processing, the final preparation of the crystalline silicon solar cell efficiency can reach 18.41%, which is an increase of 0.4%{sub abs} compared to conventional emitters with 50 ?/? sheet resistance.

  19. 17th Workshop on Crystalline Silicon Solar Cells and Modules: Materials and Processes; Workshop Proceedings

    SciTech Connect (OSTI)

    Sopori, B. L.

    2007-08-01

    The National Center for Photovoltaics sponsored the 17th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes, held in Vail, CO, August 5-8, 2007. This meeting provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. The theme of this year's meeting was 'Expanding Technology for a Future Powered by Si Photovoltaics.'

  20. Signet Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Alto, California Zip: 94306 Product: US-based manufacturer of amorphous silicon thin-film modules. References: Signet Solar Inc1 This article is a stub. You can help OpenEI by...

  1. Low temperature front surface passivation of interdigitated back contact silicon heterojunction solar cell

    SciTech Connect (OSTI)

    Shu, Brent; Das, Ujjwal; Jani, Omkar; Hegedus, Steve; Birkmire, Robert

    2009-06-08

    The interdigitated back contact silicon heterojunction (IBC-SHJ) solar cell requires a low temperature front surface passivation/anti-reflection structure. Conventional silicon surface passivation using SiO2 or a-SiNx is performed at temperature higher than 400C, which is not suitable for the IBC-SHJ cell. In this paper, we propose a PECVD a-Si:H/a-SiNx:H/a-SiC:H stack structure to passivate the front surface of crystalline silicon at low temperature. The optical properties and passivation quality of this structure are characterized and solar cells using this structure are fabricated. With 2 nm a-Si:H layer, the stack structure exhibits stable passivation with effective minority carrier lifetime higher than 2 ms, and compatible with IBC-SHJ solar cell processing. A critical advantage of this structure is that the SiC allows it to be HF resistant, thus it can be deposited as the first step in the process. This protects the a-Si/c-Si interface and maintains a low surface recombination velocity.

  2. GaNPAs Solar Cells that Can Be Lattice-Matched to Silicon

    SciTech Connect (OSTI)

    Geisz, J. F.; Friedman, D. J.; McMahon, W. E.; Ptak, A. J.; Kibbler, A. E.; Olson, J. M.; Kurtz, S.; Kramer, C.; Young, M.; Duda, A.; Reedy, R. C.; Keyes, B. M.; Dippo, P.; Metzger, W. K.

    2003-05-01

    III-V semiconductors grown on silicon substrates are very attractive for lower-cost, high-efficiency multijunction solar cells, but lattice-mismatched alloys that result in high dislocation densities have been unable to achieve satisfactory performance. GaNxP1-x-yAsy is a direct-gap III-V alloy that can be grown lattice-matched to Si when y= 4.7x - 0.1. We have proposed the use of lattice-matched GaNPAs on silicon for high-efficiency multijunction solar cells. We have grown GaNxP1-x-yAsy on GaP (with a similar lattice constant to silicon) by metal-organic chemical vapor phase epitaxy with direct bandgaps in the range of 1.5 to 2.0 eV. We have demonstrated the performance of single-junction GaNxP1-x-yAsy solar cells grown on GaP substrates and shown improvements in material quality by reducing carbon and hydrogen impurities through optimization of growth conditions. We have achieved quantum efficiencies (QE) in these cells as high as 60% and PL lifetimes as high as 3.0 ns.

  3. Phase 2 of the array automated assembly task for the low cost silicon solar array project. Final report

    SciTech Connect (OSTI)

    Petersen, R.C.

    1980-11-01

    Studies were conducted on several fundamental aspects of electroless nickel/solder metallization for silicon solar cells. A process proposed by Motorola, which precedes the electroless nickel plating with several steps of palladium plating and heat treatment, was compared directly with single step electroless nickel plating. Work has directed toward answering specific questions concerning the effect of silicon surface oxide on nickel plating, effects of thermal stresses on the metallization, sintering of nickel plated on silicon, and effects of exposure to the plating solution on solar cell characteristics. The Motorola process was compared with simple electroless nickel plating in a series of parallel experiments. Results are presented. (WHK)

  4. Low work function, stable thin films

    DOE Patents [OSTI]

    Dinh, Long N. (Concord, CA); McLean, II, William (Oakland, CA); Balooch, Mehdi (Berkeley, CA); Fehring, Jr., Edward J. (Dublin, CA); Schildbach, Marcus A. (Livermore, CA)

    2000-01-01

    Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

  5. Process For Direct Integration Of A Thin-Film Silicon P-N Junction Diode With A Magnetic Tunnel Junction

    DOE Patents [OSTI]

    Toet, Daniel (Mountain View, CA); Sigmon, Thomas W. (Albuquerque, NM)

    2005-08-23

    A process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular p-n junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.

  6. Process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction

    DOE Patents [OSTI]

    Toet, Daniel; Sigmon, Thomas W.

    2004-12-07

    A process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular p-n junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.

  7. Process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction

    DOE Patents [OSTI]

    Toet, Daniel (Mountain View, CA); Sigmon, Thomas W. (Albuquerque, NM)

    2003-01-01

    A process for direct integration of a thin-film silicon p-n junction diode with a magnetic tunnel junction for use in advanced magnetic random access memory (MRAM) cells for high performance, non-volatile memory arrays. The process is based on pulsed laser processing for the fabrication of vertical polycrystalline silicon electronic device structures, in particular p-n junction diodes, on films of metals deposited onto low temperature-substrates such as ceramics, dielectrics, glass, or polymers. The process preserves underlayers and structures onto which the devices are typically deposited, such as silicon integrated circuits. The process involves the low temperature deposition of at least one layer of silicon, either in an amorphous or a polycrystalline phase on a metal layer. Dopants may be introduced in the silicon film during or after deposition. The film is then irradiated with short pulse laser energy that is efficiently absorbed in the silicon, which results in the crystallization of the film and simultaneously in the activation of the dopants via ultrafast melting and solidification. The silicon film can be patterned either before or after crystallization.

  8. Synthesis and characterization of large-grain solid-phase crystallized polycrystalline silicon thin films

    SciTech Connect (OSTI)

    Kumar, Avishek, E-mail: avishek.kumar@nus.edu.sg, E-mail: dalapatig@imre.a-star.edu.sg [Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Block E3A, #06-01, Singapore 117574 (Singapore); Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583 (Singapore); Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore); Law, Felix; Widenborg, Per I. [Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Block E3A, #06-01, Singapore 117574 (Singapore); Dalapati, Goutam K., E-mail: avishek.kumar@nus.edu.sg, E-mail: dalapatig@imre.a-star.edu.sg; Subramanian, Gomathy S.; Tan, Hui R. [Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore); Aberle, Armin G. [Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Block E3A, #06-01, Singapore 117574 and Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583 (Singapore)

    2014-11-01

    n-type polycrystalline silicon (poly-Si) films with very large grains, exceeding 30??m in width, and with high Hall mobility of about 71.5?cm{sup 2}/V s are successfully prepared by the solid-phase crystallization technique on glass through the control of the PH{sub 3} (2% in H{sub 2})/SiH{sub 4} gas flow ratio. The effect of this gas flow ratio on the electronic and structural quality of the n-type poly-Si thin film is systematically investigated using Hall effect measurements, Raman microscopy, and electron backscatter diffraction (EBSD), respectively. The poly-Si grains are found to be randomly oriented, whereby the average area weighted grain size is found to increase from 4.3 to 18??m with increase of the PH{sub 3} (2% in H{sub 2})/SiH{sub 4} gas flow ratio. The stress in the poly-Si thin films is found to increase above 900?MPa when the PH{sub 3} (2% in H{sub 2})/SiH{sub 4} gas flow ratio is increased from 0.025 to 0.45. Finally, high-resolution transmission electron microscopy, high angle annular dark field-scanning tunneling microscopy, and EBSD are used to identify the defects and dislocations caused by the stress in the fabricated poly-Si films.

  9. Pyroelectric response of lead zirconate titanate thin films on silicon: Effect of thermal stresses

    SciTech Connect (OSTI)

    Kesim, M. T.; Zhang, J.; Alpay, S. P.; Trolier-McKinstry, S.; Mantese, J. V.; Whatmore, R. W.

    2013-11-28

    Ferroelectric lead zirconate titanate [Pb(Zr{sub x}Ti{sub 1-x}O){sub 3}, (PZT x:1-x)] has received considerable interest for applications related to uncooled infrared devices due to its large pyroelectric figures of merit near room temperature, and the fact that such devices are inherently ac coupled, allowing for simplified image post processing. For ferroelectric films made by industry-standard deposition techniques, stresses develop in the PZT layer upon cooling from the processing/growth temperature due to thermal mismatch between the film and the substrate. In this study, we use a non-linear thermodynamic model to investigate the pyroelectric properties of polycrystalline PZT thin films for five different compositions (PZT 40:60, PZT 30:70, PZT 20:80, PZT 10:90, PZT 0:100) on silicon as a function of processing temperature (25800?C). It is shown that the in-plane thermal stresses in PZT thin films alter the out-of-plane polarization and the ferroelectric phase transformation temperature, with profound effect on the pyroelectric properties. PZT 30:70 is found to have the largest pyroelectric coefficient (0.042??C cm{sup ?2}?C{sup ?1}, comparable to bulk values) at a growth temperature of 550?C; typical to what is currently used for many deposition processes. Our results indicate that it is possible to optimize the pyroelectric response of PZT thin films by adjusting the Ti composition and the processing temperature, thereby, enabling the tailoring of material properties for optimization relative to a specific deposition process.

  10. Intermixing at the absorber-buffer layer interface in thin-film solar

    Office of Scientific and Technical Information (OSTI)

    cells: The electronic effects of point defects in Cu(In,Ga)(Se,S){sub 2} and Cu{sub 2}ZnSn(Se,S){sub 4} devices (Journal Article) | SciTech Connect Intermixing at the absorber-buffer layer interface in thin-film solar cells: The electronic effects of point defects in Cu(In,Ga)(Se,S){sub 2} and Cu{sub 2}ZnSn(Se,S){sub 4} devices Citation Details In-Document Search Title: Intermixing at the absorber-buffer layer interface in thin-film solar cells: The electronic effects of point defects in

  11. High-Efficiency GaAs Thin-Film Solar Cell Reliability | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy GaAs Thin-Film Solar Cell Reliability High-Efficiency GaAs Thin-Film Solar Cell Reliability Presented at the PV Module Reliability Workshop, February 26 - 27 2013, Golden, Colorado PDF icon pvmrw13_ps2_alta_li.pdf More Documents & Publications Agenda for the PV Module Reliability Workshop, February 26 - 27 2013, Golden, Colorado Sensitivities of I-V Parameters in C-Si PV Modules of Hygrothermal Stress The Acceleration of Degradation by HAST and Air-HAST in c-Si PV Modules

  12. Thin-film flat-plate solar collectors for low-cost manufacture and installation

    SciTech Connect (OSTI)

    Andrews, J.W.; Wilhelm, W.G.

    1980-03-01

    A flat-plate solar energy collector design using thin-film plastics in both the absorber and glazing is described. The design approach proceeded in two steps. First, cost constraints on solar collectors were determined using reasonable economic projections. Second, engineering was applied only to those ideas which had hope of falling within those cost boundaries. The use of thin-film plastics appeared most attractive according to these criteria. The nature of the marketing and distribution network can be expected to have a strong impact on the final installed cost of the collector; the proposed design has characteristics which could make possible a reduced price markup.

  13. Recent improvements in materials for thin GaAs and multibandgap solar cells

    SciTech Connect (OSTI)

    Benner, J.P.

    1985-05-01

    The High Efficiency Concepts Program at SERI supports research on III-V compound semiconductors with the objective of achieving the maximum attainable photovoltaic conversion efficiencies for terrestrial solar electric power. The outcome of this research may also affect the future of space photovoltaic cells. While the interest in thin-film, high-efficiency solar cells for terrestrial applications is driven principally by consideration of system costs, such cells would also improve the power density of space power arrays.

  14. NREL Achieves World Record Performance For Thin Film Solar Cell Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL Achieves World Record Performance For Thin Film Solar Cell Technology Golden, Colo., May 10, 1996 -- Scientists at the U. S. Department of Energy's National Renewable Energy Laboratory (NREL) have achieved a world record in the performance of an advanced solar cell technology designed to have a major impact on the cost of electricity from the sun. NREL established a new world record "sunlight-to-electricity" efficiency of 17.7 percent with a compound semiconductor called copper

  15. Real time intelligent process control system for thin film solar cell manufacturing

    SciTech Connect (OSTI)

    George Atanasoff

    2010-10-29

    This project addresses the problem of lower solar conversion efficiency and waste in the typical solar cell manufacturing process. The work from the proposed development will lead toward developing a system which should be able to increase solar panel conversion efficiency by an additional 12-15% resulting in lower cost panels, increased solar technology adoption, reduced carbon emissions and reduced dependency on foreign oil. All solar cell manufacturing processes today suffer from manufacturing inefficiencies that currently lead to lower product quality and lower conversion efficiency, increased product cost and greater material and energy consumption. This results in slower solar energy adoption and extends the time solar cells will reach grid parity with traditional energy sources. The thin film solar panel manufacturers struggle on a daily basis with the problem of thin film thickness non-uniformity and other parameters variances over the deposited substrates, which significantly degrade their manufacturing yield and quality. Optical monitoring of the thin films during the process of the film deposition is widely perceived as a necessary step towards resolving the non-uniformity and non-homogeneity problem. In order to enable the development of an optical control system for solar cell manufacturing, a new type of low cost optical sensor is needed, able to acquire local information about the panel under deposition and measure its local characteristics, including the light scattering in very close proximity to the surface of the film. This information cannot be obtained by monitoring from outside the deposition chamber (as traditional monitoring systems do) due to the significant signal attenuation and loss of its scattering component before the reflected beam reaches the detector. In addition, it would be too costly to install traditional external in-situ monitoring systems to perform any real-time monitoring over large solar panels, since it would require significant equipment refurbishing needed for installation of multiple separate ellipsometric systems, and development of customized software to control all of them simultaneously. The proposed optical monitoring system comprises AccuStratas fiber optics sensors installed inside the thin film deposition equipment, a hardware module of different components (beyond the scope of this project) and our software program with iterative predicting capability able to control material bandgap and surface roughness as films are deposited. Our miniature fiber optics monitoring sensors are installed inside the vacuum chamber compartments in very close proximity where the independent layers are deposited (an option patented by us in 2003). The optical monitoring system measures two of the most important parameters of the photovoltaic thin films during deposition on a moving solar panel - material bandgap and surface roughness. In this program each sensor array consists of two fiber optics sensors monitoring two independent areas of the panel under deposition. Based on the monitored parameters and their change in time and from position to position on the panel, the system is able to provide to the equipment operator immediate information about the thin films as they are deposited. This DoE Supply Chain program is considered the first step towards the development of intelligent optical control system capable of dynamically adjusting the manufacturing process on-the-fly in order to achieve better performance. The proposed system will improve the thin film solar cell manufacturing by improving the quality of the individual solar cells and will allow for the manufacturing of more consistent and uniform products resulting in higher solar conversion efficiency and manufacturing yield. It will have a significant impact on the multibillion-dollar thin film solar market. We estimate that the financial impact of these improvements if adopted by only 10% of the industry ($7.7 Billion) would result in about $1.5 Billion in savings by 2015 (at the assumed 20% improvement). This can b

  16. High efficiency multijunction amorphous silicon alloy-based solar cells and modules

    SciTech Connect (OSTI)

    Guha, S.; Yang, J.; Banerjeee, A.; Glatfelter, T.; Hoffman, K.; Xu, X. )

    1994-06-30

    We have achieved initial efficiency of 11.4% as confirmed by National Renewable Energy Laboratory (NREL) on a multijunction amorphous silicon alloy photovoltaic module of one-square-foot-area. [bold This] [bold is] [bold the] [bold highest] [bold initial] [bold efficiency] [bold confirmed] [bold by] [bold NREL] [bold for] [bold any] [bold thin] [bold film] [bold photovoltaic] [bold module]. After light soaking for 1000 hours at 50 [degree]C under one-sun illumination, a module with initial efficiency of 11.1% shows a stabilized efficiency of 9.5%. Key factors that led to this high performance are discussed.

  17. Novel wide band gap materials for highly efficient thin film tandem solar cells

    SciTech Connect (OSTI)

    Brian E. Hardin, Stephen T. Connor, Craig H. Peters

    2012-06-11

    Tandem solar cells (TSCs), which use two or more materials to absorb sunlight, have achieved power conversion efficiencies of >25% versus 11-20% for commercialized single junction solar cell modules. The key to widespread commercialization of TSCs is to develop the wide-band, top solar cell that is both cheap to fabricate and has a high open-circuit voltage (i.e. >1V). Previous work in TSCs has generally focused on using expensive processing techniques with slow growth rates resulting in costs that are two orders of magnitude too expensive to be used in conventional solar cell modules. The objective of the PLANT PV proposal was to investigate the feasibility of using Ag(In,Ga)Se2 (AIGS) as the wide-bandgap absorber in the top cell of a thin film tandem solar cell (TSC). Despite being studied by very few in the solar community, AIGS solar cells have achieved one of the highest open-circuit voltages within the chalcogenide material family with a Voc of 949mV when grown with an expensive processing technique (i.e. Molecular Beam Epitaxy). PLANT PVâ??s goal in Phase I of the DOE SBIR was to 1) develop the chemistry to grow AIGS thin films via solution processing techniques to reduce costs and 2) fabricate new device architectures with high open-circuit voltage to produce full tandem solar cells in Phase II. PLANT PV attempted to translate solution processing chemistries that were successful in producing >12% efficient Cu(In,Ga)Se2 solar cells by replacing copper compounds with silver. The main thrust of the research was to determine if it was possible to make high quality AIGS thin films using solution processing and to fully characterize the materials properties. PLANT PV developed several different types of silver compounds in an attempt to fabricate high quality thin films from solution. We found that silver compounds that were similar to the copper based system did not result in high quality thin films. PLANT PV was able to deposit AIGS thin films using a mixture of solution and physical vapor deposition processing, but these films lacked the p-type doping levels that are required to make decent solar cells. Over the course of the project PLANT PV was able to fabricate efficient CIGS solar cells (8.7%) but could not achieve equivalent performance using AIGS. During the nine-month grant PLANT PV set up a variety of thin film characterization tools (e.g. drive-level capacitance profiling) at the Molecular Foundry, a Department of Energy User Facility, that are now available to both industrial and academic researchers via the grant process. PLANT PV was also able to develop the back end processing of thin film solar cells at Lawrence Berkeley National Labs to achieve 8.7% efficient CIGS solar cells. This processing development will be applied to other types of thin film PV cells at the Lawrence Berkeley National Labs. While PLANT PV was able to study AIGS film growth and optoelectronic properties we concluded that AIGS produced using these methods would have a limited efficiency and would not be commercially feasible. PLANT PV did not apply for the Phase II of this grant.

  18. Method and apparatus for fabricating a thin-film solar cell utilizing a hot wire chemical vapor deposition technique

    DOE Patents [OSTI]

    Wang, Qi; Iwaniczko, Eugene

    2006-10-17

    A thin-film solar cell is provided. The thin-film solar cell comprises an a-SiGe:H (1.6 eV) n-i-p solar cell having a deposition rate of at least ten (10) .ANG./second for the a-SiGe:H intrinsic layer by hot wire chemical vapor deposition. A method for fabricating a thin film solar cell is also provided. The method comprises depositing a n-i-p layer at a deposition rate of at least ten (10) .ANG./second for the a-SiGe:H intrinsic layer.

  19. Method of forming particulate materials for thin-film solar cells

    DOE Patents [OSTI]

    Eberspacher, Chris; Pauls, Karen Lea

    2004-11-23

    A method for preparing particulate materials useful in fabricating thin-film solar cells is disclosed. Particulate materials is prepared by the method include for example materials comprising copper and indium and/or gallium in the form of single-phase, mixed-metal oxide particulates; multi-phase, mixed-metal particulates comprising a metal oxide; and multinary metal particulates.

  20. Carrier Selective, Passivated Contacts for High Efficiency Silicon Solar Cells based on Transparent Conducting Oxides

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Young, David L.; Nemeth, William; Grover, Sachit; Norman, Andrew; Yuan, Hao-Chih; Lee, Benjamin G.; LaSalvia, Vincenzo; Stradins, Paul

    2014-01-01

    We describe the design, fabrication and results of passivated contacts to n-type silicon utilizing thin SiO2 and transparent conducting oxide layers. High temperature silicon dioxide is grown on both surfaces of an n-type wafer to a thickness <50 Å, followed by deposition of tin-doped indium oxide (ITO) and a patterned metal contacting layer. As deposited, the thin-film stack has a very high J0,contact, and a non-ohmic, high contact resistance. However, after a forming gas anneal, the passivation quality and the contact resistivity improve significantly. The contacts are characterized by measuring the recombination parameter of the contact (J0,contact) and the specificmore » contact resistivity (ρcontact) using a TLM pattern. The best ITO/SiO2 passivated contact in this study has J0,contact = 92.5 fA/cm2 and ρcontact = 11.5 mOhm-cm2. These values are placed in context with other passivating contacts using an analysis that determines the ultimate efficiency and the optimal area fraction for contacts for a given set of (J0,contact, ρcontact) values. The ITO/SiO2 contacts are found to have a higher J0,contact, but a similar ρcontact compared to the best reported passivated contacts.« less

  1. Thin film solar cell configuration and fabrication method

    DOE Patents [OSTI]

    Menezes, Shalini

    2009-07-14

    A new photovoltaic device configuration based on an n-copper indium selenide absorber and a p-type window is disclosed. A fabrication method to produce this device on flexible or rigid substrates is described that reduces the number of cell components, avoids hazardous materials, simplifies the process steps and hence the costs for high volume solar cell manufacturing.

  2. Thin-Film Solar Cell Fabricated on a Flexible Metallic Substrate

    DOE Patents [OSTI]

    Tuttle, J. R.; Noufi, R.; Hasoon, F. S.

    2006-05-30

    A thin-film solar cell (10) is provided. The thin-film solar cell (10) comprises a flexible metallic substrate (12) having a first surface and a second surface. A back metal contact layer (16) is deposited on the first surface of the flexible metallic substrate (12). A semiconductor absorber layer (14) is deposited on the back metal contact. A photoactive film deposited on the semiconductor absorber layer (14) forms a heterojunction structure and a grid contact (24) deposited on the heterjunction structure. The flexible metal substrate (12) can be constructed of either aluminium or stainless steel. Furthermore, a method of constructing a solar cell is provided. The method comprises providing an aluminum substrate (12), depositing a semiconductor absorber layer (14) on the aluminum substrate (12), and insulating the aluminum substrate (12) from the semiconductor absorber layer (14) to inhibit reaction between the aluminum substrate (12) and the semiconductor absorber layer (14).

  3. Thin-film solar cell fabricated on a flexible metallic substrate

    DOE Patents [OSTI]

    Tuttle, John R.; Noufi, Rommel; Hasoon, Falah S.

    2006-05-30

    A thin-film solar cell (10) is provided. The thin-film solar cell (10) comprises a flexible metallic substrate (12) having a first surface and a second surface. A back metal contact layer (16) is deposited on the first surface of the flexible metallic substrate (12). A semiconductor absorber layer (14) is deposited on the back metal contact. A photoactive film deposited on the semiconductor absorber layer (14) forms a heterojunction structure and a grid contact (24) deposited on the heterjunction structure. The flexible metal substrate (12) can be constructed of either aluminium or stainless steel. Furthermore, a method of constructing a solar cell is provided. The method comprises providing an aluminum substrate (12), depositing a semiconductor absorber layer (14) on the aluminum substrate (12), and insulating the aluminum substrate (12) from the semiconductor absorber layer (14) to inhibit reaction between the aluminum substrate (12) and the semiconductor absorber layer (14).

  4. SolarMorph Pte Ltd | Open Energy Information

    Open Energy Info (EERE)

    Pte Ltd Place: Singapore Product: Singapore-based manufacturer of amorphous silicon thin-film products. References: SolarMorph Pte Ltd1 This article is a stub. You can help...

  5. HelioSphera formerly Next Solar SA | Open Energy Information

    Open Energy Info (EERE)

    Name: HelioSphera (formerly Next Solar SA) Place: Athens, Greece Zip: 11523 Product: Greek thin-film silicon PV module manufacturer with a 60MW plant in Tripolis. Coordinates:...

  6. Solar Bancorp Group of Companies | Open Energy Information

    Open Energy Info (EERE)

    Zip: M5H 3L5 Product: Toronto-based holding company with interest in financial and marketing servies, and thin film silicon manufacturing. References: Solar Bancorp Group of...

  7. Silicon sheet with molecular beam epitaxy for high efficiency solar cells. Final technical report, March 22, 1982-April 30, 1984

    SciTech Connect (OSTI)

    Not Available

    1984-01-01

    A two-year program has been carried out for the Jet Propulsion Laboratory in which the UCLA silicon MBE facility has been used to attempt to grow silicon solar cells of high efficiency. MBE ofers the potential of growing complex and arbitrary doping profiles with 10 A depth resolution. It is the only technique taht can readily grow built-in front and back surface fields of any desired depth and value in silicon solar cells, or the more complicated profiles needed for a double junction cascade cell, all in silicon, connected in series by a tunnel junction. Although the dopant control required for such structures has been demonstrated in silicon by UCLA, crystal quality at the p-n junctions is still too poor to allow the other advantages to be exploited. Results from other laboratories indicate that this problem will soon be overcome. A computer analysis of the double cascade all in silicon shows that efficiencies can be raised over that of any single silicon cell by 1 or 2%, and that open circuit voltage of almost twice that of a single cell should be possible.

  8. 17.1%-Efficient Multi-Scale-Textured Black Silicon Solar Cells without Dielectric Antireflection Coating

    SciTech Connect (OSTI)

    Toor, F.; Page, M. R.; Branz, H. M.; Yuan, H. C.

    2011-01-01

    In this work we present 17.1%-efficient p-type single crystal Si solar cells with a multi-scale-textured surface and no dielectric antireflection coating. Multi-scale texturing is achieved by a gold-nanoparticle-assisted nanoporous etch after conventional micron scale KOH-based pyramid texturing (pyramid black etching). By incorporating geometric enhancement of antireflection, this multi-scale texturing reduces the nanoporosity depth required to make silicon `black' compared to nanoporous planar surfaces. As a result, it improves short-wavelength spectral response (blue response), previously one of the major limiting factors in `black-Si' solar cells. With multi-scale texturing, the spectrum-weighted average reflectance from 350- to 1000-nm wavelength is below 2% with a 100-nm deep nanoporous layer. In comparison, roughly 250-nm deep nanopores are needed to achieve similar reflectance on planar surface. Here, we characterize surface morphology, reflectivity and solar cell performance of the multi-scale textured solar cells.

  9. Reaching Grid Parity Using BP Solar Crystalline Silicon Technology: A Systems Class Application

    SciTech Connect (OSTI)

    Cunningham, Daniel W; Wohlgemuth, John; Carlson, David E; Clark, Roger F; Gleaton, Mark; Posbic, John P; Zahler, James

    2010-12-06

    The primary target market for this program was the residential and commercial PV markets, drawing on BP Solar's premium product and service offerings, brand and marketing strength, and unique routes to market. These two markets were chosen because: (1) in 2005 they represented more than 50% of the overall US PV market; (2) they are the two markets that will likely meet grid parity first; and (3) they are the two market segments in which product development can lead to the added value necessary to generate market growth before reaching grid parity. Federal investment in this program resulted in substantial progress toward the DOE TPP target, providing significant advancements in the following areas: (1) Lower component costs particularly the modules and inverters. (2) Increased availability and lower cost of silicon feedstock. (3) Product specifically developed for residential and commercial applications. (4) Reducing the cost of installation through optimization of the products. (5) Increased value of electricity in mid-term to drive volume increases, via the green grid technology. (6) Large scale manufacture of PV products in the US, generating increased US employment in manufacturing and installation. To achieve these goals BP Solar assembled a team that included suppliers of critical materials, automated equipment developers/manufacturers, inverter and other BOS manufacturers, a utility company, and University research groups. The program addressed all aspects of the crystalline silicon PV business from raw materials (particularly silicon feedstock) through installation of the system on the customers site. By involving the material and equipment vendors, we ensured that supplies of silicon feedstock and other PV specific materials like encapsulation materials (EVA and cover glass) will be available in the quantities required to meet the DOE goals of 5 to 10 GW of installed US PV by 2015 and at the prices necessary for PV systems to reach grid parity in 2015. This final technical report highlights the accomplishments of the BP Solar technical team from 2006 to the end of the project in February 2010. All the main contributors and team members are recognized for this accomplishment and their endeavors are recorded in the twelve main tasks described here.

  10. Silicon materials task of the low cost solar array project (Phase III). Effects of impurities and processing on silicon solar cells. Phase III summary and seventeenth quarterly report, Volume 2: analysis of impurity behavior

    SciTech Connect (OSTI)

    Hopkins, R.H.; Davis, J.R.; Rohatgi, A.; Campbell, R.B.; Blais, P.D.; Rai-Choudhury, P.; Stapleton, R.E.; Mollenkopf, H.C.; McCormick, J.R.

    1980-01-23

    The object of this phase of the program has been to investigate the effects of various processes, metal contaminants and contaminant-process interactions on the properties of silicon and on the performance of terrestrial silicon solar cells. The study encompassed topics including thermochemical (gettering) treatments, base doping concentration, base doping type (n vs. p), grain boundary-impurity interaction, non-uniformity of impurity distribution, long term effects of impurities, as well as synergic and complexing phenomena. The program approach consists in: (1) the growth of doubly and multiply-doped silicon single crystals containing a baseline boron or phosphorus dopant and specific impurities which produce deep levels in the forbidden band gap; (2) assessment of these crystals by chemical, microstructural, electrical and solar cell tests; (3) correlation of the impurity type and concentration with crystal quality and device performance; and (4) delineation of the role of impurities and processing on subsequent silicon solar cell performance. The overall results reported are based on the assessment of nearly 200 silicon ingots. (WHK)

  11. Structural characterisation of BaTiO{sub 3} thin films deposited on SrRuO{sub 3}/YSZ buffered silicon substrates and silicon microcantilevers

    SciTech Connect (OSTI)

    Colder, H.; Jorel, C. Mchin, L.; Domengs, B.; Marie, P.; Boisserie, M.; Guillon, S.; Nicu, L.; Galdi, A.

    2014-02-07

    We report on the progress towards an all epitaxial oxide layer technology on silicon substrates for epitaxial piezoelectric microelectromechanical systems. (101)-oriented epitaxial tetragonal BaTiO{sub 3} (BTO) thin films were deposited at two different oxygen pressures, 5.10{sup ?2} mbar and 5.10{sup ?3} mbar, on SrRuO{sub 3}/Yttria-stabilized zirconia (YSZ) buffered silicon substrates by pulsed laser deposition. The YSZ layer full (001) orientation allowed the further growth of a fully (110)-oriented conductive SrRuO{sub 3} electrode as shown by X-ray diffraction. The tetragonal structure of the BTO films, which is a prerequisite for the piezoelectric effect, was identified by Raman spectroscopy. In the BTO film deposited at 5.10{sup ?2} mbar strain was mostly localized inside the BTO grains whereas at 5.10{sup ?3} mbar, it was localized at the grain boundaries. The BTO/SRO/YSZ layers were finally deposited on Si microcantilevers at an O{sub 2} pressure of 5.10{sup ?3} mbar. The strain level was low enough to evaluate the BTO Young modulus. Transmission electron microscopy (TEM) was used to investigate the epitaxial quality of the layers and their epitaxial relationship on plain silicon wafers as well as on released microcantilevers, thanks to Focused-Ion-Beam TEM lamella preparation.

  12. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

    SciTech Connect (OSTI)

    Chu, T.L. )

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

  13. MOCVD growth of GaAs solar cells on silicon substrates

    SciTech Connect (OSTI)

    Vernon, S.M.; Haven, V.E.; Geoffroy, L.M.; Sanfacon, M.M.; Mastrovito, A.L. )

    1992-12-01

    This paper reports advances in the development of solar cells made from GaAs-on-Si structures prepared by metalorganic chemical vapor deposition (MOCVD). The use of concentrator cells, operating at [similar to]200 suns, has led to the efficiency achievements of 21.3% (AM1.5D) for a GaAs-on-Si solar cell, and 27.6 (AM1.5D) for a homoepitaxial GaAs cell. The development of epitaxial multilayer dielectric mirrors (Bragg reflectors), as back-surface reflectors in thin-film GaAs cells, on both Si and GaAs substrates, is shown to lead to modest efficiency increases, over that of conventional designs.

  14. Optimization of the optical properties of nanostructured silicon surfaces for solar cell applications

    SciTech Connect (OSTI)

    Zhou, Di; Pennec, Y.; Djafari-Rouhani, B.; Lambert, Y.; Deblock, Y.; Stiévenard, D.; Cristini-Robbe, O.; Xu, T.; Faucher, M.

    2014-04-07

    Surface nanostructuration is an important challenge for the optimization of light trapping in solar cell. We present simulations on both the optical properties and the efficiency of micro pillars—MPs—or nanocones—NCs—silicon based solar cells together with measurements on their associated optical absorption. We address the simulation using the Finite Difference Time Domain method, well-adapted to deal with a periodic set of nanostructures. We study the effect of the period, the bottom diameter, the top diameter, and the height of the MPs or NCs on the efficiency, assuming that one absorbed photon induces one exciton. This allows us to give a kind of abacus involving all the geometrical parameters of the nanostructured surface with regard to the efficiency of the associated solar cell. We also show that for a given ratio of the diameter over the period, the best efficiency is obtained for small diameters. For small lengths, MPs are extended to NCs by changing the angle between the bottom surface and the vertical face of the MPs. The best efficiency is obtained for an angle of the order of 70°. Finally, nanostructures have been processed and allow comparing experimental results with simulations. In every case, a good agreement is found.

  15. Microscopic Measurements of Electrical Potential in Hydrogenated Nanocrystalline Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Moutinho, H. R.; Reedy, R. C.; Al-Jassim, M. M.; Yan, B.; Yue, G.; Sivec, L.; Yang, J.; Guha, S.; Tong, X.

    2012-04-01

    We report on a direct measurement of electrical potential and field profiles across the n-i-p junction of hydrogenated nanocrystalline silicon (nc-Si:H) solar cells, using the nanometer-resolution potential imaging technique of scanning Kelvin probe force microscopy (SKPFM). It was observed that the electric field is nonuniform across the i layer. It is much higher in the p/i region than in the middle and the n/i region, illustrating that the i layer is actually slightly n-type. A measurement on a nc-Si:H cell with a higher oxygen impurity concentration shows that the nonuniformity of the electric field is much more pronounced than in samples having a lower O impurity, indicating that O is an electron donor in nc-Si:H materials. This nonuniform distribution of electric field implies a mixture of diffusion and drift of carrier transport in the nc-Si:H solar cells. The composition and structure of these nc-Si:H cells were further investigated by using secondary-ion mass spectrometry and Raman spectroscopy, respectively. The effects of impurity and structural properties on the electrical potential distribution and solar cell performance are discussed.

  16. Characterization of the Electronic and Chemical Structure at the Thin Film Solar Cell Interfaces: June 2005 -- June 2009

    SciTech Connect (OSTI)

    Heske, C.

    2009-09-01

    Study using photoelectron spectroscopy, inverse photoemission, and X-ray absorption and emission to derive the electronic structure of interfaces in CIGSS and CdTe thin-film solar cells.

  17. Final project report - CRADA with United Solar Technologies and Pacific Northwest Laboratory (PNL-021): Thin film materials for low-cost high performance solar concentrators

    SciTech Connect (OSTI)

    Martin, P.M.; Affinito, J.D.; Gross, M.E.; Bennett, W.D.

    1995-03-01

    The objectives of this project were as follows: To develop and evaluate promising low-cost dielectric and polymer-protected thin-film reflective metal coatings to be applied to preformed continuously-curved solar reflector panels to enhance their solar reflectance, and to demonstrate protected solar reflective coatings on preformed solar concentrator panels. The opportunity for this project arose from a search by United Solar Technologies (UST) for organizations and facilities capable of applying reflective coatings to large preformed panels. PNL was identified as being uniquely qualified to participate in this collaborative project.

  18. Eighth workshop on crystalline silicon solar cell materials and processes: Extended abstracts and papers

    SciTech Connect (OSTI)

    1998-08-01

    The theme of this workshop is Supporting the Transition to World Class Manufacturing. This workshop provides a forum for an informal exchange of information between researchers in the photovoltaic and non-photovoltaic fields on various aspects of impurities and defects in silicon, their dynamics during device processing, and their application in defect engineering. This interaction helps establish a knowledge base that can be used for improving device fabrication processes to enhance solar-cell performance and reduce cell costs. It also provides an excellent opportunity for researchers from industry and universities to recognize mutual needs for future joint research. The workshop format features invited review presentations, panel discussions, and two poster sessions. The poster sessions create an opportunity for both university and industrial researchers to present their latest results and provide a natural forum for extended discussions and technical exchanges.

  19. Large-area Silicon-Film{trademark} panels and solar cells. Final technical report, July 1995--March 1998

    SciTech Connect (OSTI)

    Rand, J.A.; Bai, Y.; Barnett, A.M.; Culik, J.S.; Ford, D.H.; Hall, R.B.; Kendall, C.L.

    1998-09-01

    This report will detail substantial improvements in each of the task areas. A number of new products were developed, including a 130 kW array built using a new panel design. Improvements in laboratory-scale solar cell processing resulted in a confirmed efficiency of 16.6%. A new Silicon-Film{trademark} production sheet machine was built which increased throughput by 70%. Three solar cell fabrication processes were converted from low throughout batch processes to high throughput, continuous, belt processes. These new processes are capable of processing sheet over 31 cm in width. Finally, a new Silicon-Film{trademark} sheet machine was built that demonstrated a sheet width of 38 cm. This tool enabled AstroPower to demonstrate a wide range of solar cell sizes, many of which have generated considerable market interest.

  20. Laser annealing of ion implanted CZ silicon for solar cell junction formation. Quarterly report No. 1

    SciTech Connect (OSTI)

    Katzeff, J. S.

    1980-07-01

    A project to evaluate the merits of large spot size pulsed laser annealing of ion implanted silicon wafers for junction formation on solar cells is described. A Q-switched Nd:Glass laser system is used operating in the 1064 (regular) and 532 (with frequency doubler) nm wavelengths. The laser output is in excess of 30 joules with a 20 to 50 ns pulse duration. Material used in this investigation is 3-inch diameter CZ silicon, P-type 0.014 inches thick, 10..cap omega..-cm resistivity, <100> orientation. Three wafer surface conditions are being evaluated in this pulse annealing investigation: chem-polished, texture etched, and flash etched. Annealing was performed with and without beam homogenization. Both modes showed excellent lattice recovery from the implant-induced damage as analyzed using Rutherford backscattering techniques. Homogenization of the beam was performed using a fused silica rod configured with a 90/sup 0/ bend. The unhomogenized annealing was performed using a plano-concave lens. Fabrication of laser annealed cells using both modes is forthcoming.

  1. Processing and modeling issues for thin-film solar cell devices. Final report

    SciTech Connect (OSTI)

    Birkmire, R.W.; Phillips, J.E.

    1997-11-01

    During the third phase of the subcontract, IEC researchers have continued to provide the thin film PV community with greater depth of understanding and insight into a wide variety of issues including: the deposition and characterization of CuIn{sub 1-x}Ga{sub x}Se{sub 2}, a-Si, CdTe, CdS, and TCO thin films; the relationships between film and device properties; and the processing and analysis of thin film PV devices. This has been achieved through the systematic investigation of all aspects of film and device production and through the analysis and quantification of the reaction chemistries involved in thin film deposition. This methodology has led to controlled fabrications of 15% efficient CuIn{sub 1-x}Ga{sub x}Se{sub 2} solar cells over a wide range of Ga compositions, improved process control of the fabrication of 10% efficient a-Si solar cells, and reliable and generally applicable procedures for both contacting and doping films. Additional accomplishments are listed below.

  2. Dual mechanical behaviour of hydrogen in stressed silicon nitride thin films

    SciTech Connect (OSTI)

    Volpi, F. Braccini, M.; Pasturel, A.; Devos, A.; Raymond, G.; Morin, P.

    2014-07-28

    In the present article, we report a study on the mechanical behaviour displayed by hydrogen atoms and pores in silicon nitride (SiN) films. A simple three-phase model is proposed to relate the physical properties (stiffness, film stress, mass density, etc.) of hydrogenated nanoporous SiN thin films to the volume fractions of hydrogen and pores. This model is then applied to experimental data extracted from films deposited by plasma enhanced chemical vapour deposition, where hydrogen content, stress, and mass densities range widely from 11% to 30%, ?2.8 to 1.5?GPa, and 2.0 to 2.8?g/cm{sup 3}, respectively. Starting from the conventional plotting of film's Young's modulus against film porosity, we first propose to correct the conventional calculation of porosity volume fraction with the hydrogen content, thus taking into account both hydrogen mass and concentration. The weight of this hydrogen-correction is found to evolve linearly with hydrogen concentration in tensile films (in accordance with a simple mass correction of the film density calculation), but a clear discontinuity is observed toward compressive stresses. Then, the effective volume occupied by hydrogen atoms is calculated taking account of the bond type (N-H or Si-H bonds), thus allowing a precise extraction of the hydrogen volume fraction. These calculations applied to tensile films show that both volume fractions of hydrogen and porosity are similar in magnitude and randomly distributed against Young's modulus. However, the expected linear dependence of the Young's modulus is clearly observed when both volume fractions are added. Finally, we show that the stiffer behaviour of compressive films cannot be only explained on the basis of this (hydrogen?+?porosity) volume fraction. Indeed this stiffness difference relies on a dual mechanical behaviour displayed by hydrogen atoms against the film stress state: while they participate to the stiffness in compressive films, hydrogen atoms mainly behave like pores in tensile films where they do not participate to the film stiffness.

  3. Hadron-therapy beam monitoring: Towards a new generation of ultra-thin p-type silicon strip detectors

    SciTech Connect (OSTI)

    Bouterfa, M.; Aouadi, K.; Bertrand, D.; Olbrechts, B.; Delamare, R.; Raskin, J. P.; Gil, E. C.; Flandre, D.

    2011-07-01

    Hadron-therapy has gained increasing interest for cancer treatment especially within the last decade. System commissioning and quality assurance procedures impose to monitor the particle beam using 2D dose measurements. Nowadays, several monitoring systems exist for hadron-therapy but all show a relatively high influence on the beam properties: indeed, most devices consist of several layers of materials that degrade the beam through scattering and energy losses. For precise treatment purposes, ultra-thin silicon strip detectors are investigated in order to reduce this beam scattering. We assess the beam size increase provoked by the Multiple Coulomb Scattering when passing through Si, to derive a target thickness. Monte-Carlo based simulations show a characteristic scattering opening angle lower than 1 mrad for thicknesses below 20 {mu}m. We then evaluated the fabrication process feasibility. We successfully thinned down silicon wafers to thicknesses lower than 10 {mu}m over areas of several cm{sup 2}. Strip detectors are presently being processed and they will tentatively be thinned down to 20 {mu}m. Moreover, two-dimensional TCAD simulations were carried out to investigate the beam detector performances on p-type Si substrates. Additionally, thick and thin substrates have been compared thanks to electrical simulations. Reducing the pitch between the strips increases breakdown voltage, whereas leakage current is quite insensitive to strips geometrical configuration. The samples are to be characterized as soon as possible in one of the IBA hadron-therapy facilities. For hadron-therapy, this would represent a considerable step forward in terms of treatment precision. (authors)

  4. NREL: Photovoltaics Research - Thin Film Photovoltaic Partnership Project

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed the United States to attain world leadership in this area of solar technology. Three national R&D teams focused on thin-film semiconductor materials: amorphous silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium

  5. Low-temperature high-mobility amorphous IZO for silicon heterojunction solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Morales-Masis, Monica; Martin De Nicolas, Silvia; Holovsky, Jakub; De Wolf, Stefaan; Ballif, Christophe

    2015-07-13

    Parasitic absorption in the transparent conductive oxide (TCO) front electrode is one of the limitations of silicon heterojunction (SHJ) solar cells efficiency. To avoid such absorption while retaining high conductivity, TCOs with high electron mobility are preferred over those with high carrier density. Here, we demonstrate improved SHJ solar cell efficiencies by applying high-mobility amorphous indium zinc oxide (a-IZO) as the front TCO. We sputtered a-IZO at low substrate temperature and low power density and investigated the optical and electrical properties, as well as subband tail formation-quantified by the Urbach energy (EU)-as a function of the sputtering oxygen partial pressure.more » We obtain an EU as low as 128 meV for films with the highest Hall mobility of 60 cm2/Vs. When comparing the performance of a-IZO films with indium tin oxide (ITO) and hydrogenated indium oxide (IO:H), we find that IO:H (115 cm2/Vs) exhibits a similar EU of 130 meV, while ITO (25 cm2/Vs) presents a much larger EU of up to 270 meV. The high film quality, indicated by the low EU, the high mobility, and low free carrier absorption of the developed a-IZO electrodes, result in a significant current improvement, achieving conversion efficiencies over 21.5%, outperforming those with standard ITO.« less

  6. Large-area Silicon-Film{trademark} panels and solar cells. Phase 2 technical report, January 1996--December 1996

    SciTech Connect (OSTI)

    Rand, J.A.; Barnett, A.M.; Checchi, J.C.; Culik, J.S.; Collins, S.R.; Ford, D.H.; Hall, R.B.; Jackson, E.L.; Kendall, C.L.

    1997-03-01

    The Silicon-Film{trademark} process is on an accelerated path to large-scale manufacturing. A key element in that development is optimizing the specific geometry of both the Silicon-Film{trademark} sheet and the resulting solar cell. That decision has been influenced by cost factors, engineering concerns, and marketing issues. The geometry investigation has focused first on sheet nominally 15 cm wide. This sheet generated solar cells with areas of 240 cm{sup 2} and 675 cm{sup 2}. Most recently, a new sheet fabrication machine was constructed that produces Silicon-Film{trademark} with a width in excess of 30 cm. Test results have indicated that there is no limit to the width of sheet generated by this process. The new wide material has led to prototype solar cells with areas of 300, 400, and 1,800 cm{sup 2}. Significant advances in solar-cell processing have been developed in support of fabricating large-area devices, including uniform emitter diffusion and anti-reflection coatings.

  7. BeyondPV Co Ltd Bayang Solar PV | Open Energy Information

    Open Energy Info (EERE)

    Co Ltd (Bayang Solar PV) Place: Tainan, Taiwan Zip: 70955 Product: BeyondPV is an a-Si thin-film silicon PV maker based in southern Taiwan. References: BeyondPV Co Ltd (Bayang...

  8. Silicon materials task of the low cost solar array project (Phase III). Effect of impurities and processing on silicon solar cells. Phase III summary and seventeenth quarterly report, Volume 1: characterization methods for impurities in silicon and impurity effects data base

    SciTech Connect (OSTI)

    Hopkins, R.H.; Davis, J.R.; Rohatgi, A.; Campbell, R.B.; Blais, P.D.; Rai-Choudhury, P.; Stapleton, R.E.; Mollenkopf, H.C.; McCormick, J.R.

    1980-01-01

    The object of Phase III of the program has been to investigate the effects of various processes, metal contaminants and contaminant-process interactions on the performance of terrestrial silicon solar cells. The study encompassed a variety of tasks including: (1) a detailed examination of thermal processing effects, such as HCl and POCl/sub 3/ gettering on impurity behavior, (2) completion of the data base and modeling for impurities in n-base silicon, (3) extension of the data base on p-type material to include elements likely to be introduced during the production, refining, or crystal growth of silicon, (4) effects on cell performance on anisotropic impurity distributions in large CZ crystals and silicon webs, and (5) a preliminary assessment of the permanence of the impurity effects. Two major topics are treated: methods to measure and evaluate impurity effects in silicon and comprehensive tabulations of data derived during the study. For example, discussions of deep level spectroscopy, detailed dark I-V measurements, recombination lifetime determination, scanned laser photo-response, and conventional solar cell I-V techniques, as well as descriptions of silicon chemical analysis are included. Considerable data are tabulated on the composition, electrical, and solar cell characteristics of impurity-doped silicon.

  9. Large-area silicon-film{sup {trademark}} panels and solar cells. Phase I annual technical report, July 1, 1995--December 31, 1995

    SciTech Connect (OSTI)

    Rand, J.A.; Barnett, A.M.; Checchi, J.C.; Culik, J.S.

    1996-06-01

    AstroPower is establishing a low cost manufacturing process for Silicon-Film{trademark} solar cells and panels by taking advantage of the continuous nature of the Silicon-Film{trademark} technology. Under this effort, each step used in Silicon-Film{trademark} panel fabrication is being developed into a continuous/in-line manufacturing process. The following benefits are expected: an accelerated reduction of PV manufacturing cost for installed systems; a foundation for significantly increased production capacity; and a reduction in handling and waste streams. The process development will be based on a new 31-cm wide continuous Silicon-Film{trademark} sheet. Long-term goals include the development of a 24W, 30 cm x 60 cm Silicon-Film{trademark} solar cell and a manufacturing capability for a 384W, 4 inches x 8 inches Silicon-Film{trademark} panel for deployment in utility-scale applications.

  10. Radiation damage of GaAs thin-film solar cells on Si substrates

    SciTech Connect (OSTI)

    Itoh, Y.; Yamaguchi, M.; Nishioka, T.; Yamamoto, A.

    1987-01-15

    1-MeV electron irradiation damages in GaAs thin-film solar cells on Si substrates are examined for the first time. Damage constant for minority-carrier diffusion length in GaAs heteroepitaxial films on Si substrates is found to be the same as that in GaAs homoepitaxial films on GaAs substrates. This agreement suggests that GaAs/Si has the same defect introduction rate with radiation as GaAs/GaAs. The degradation of GaAs solar cells on Si with electron irradiation is less than that of GaAs solar cells on GaAs, because in the present, GaAs films on Si substrates have lower minority-carrier diffusion length compared to GaAs films on GaAs and these films are insensitive to radiation. The p/sup +/-p/sup +/-n AlGaAs-GaAs heteroface solar cell with junction depth of about 0.3 ..mu..m is concluded to be useful for a high-efficiency and radiation-resistant solar cell fabricated on a Si substrate.

  11. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Unlike commercial devices or other research efforts, this CS sensor, including packaging, is extremely thin (< 150 microm fully packaged) so that it can be unobtrusively...

  12. Cross-sectional electrostatic force microscopy of thin-film solar cells

    SciTech Connect (OSTI)

    Ballif, C.; Moutinho, H. R.; Al-Jassim, M. M.

    2001-01-15

    In a recent work, we showed that atomic force microscopy (AFM) is a powerful technique to image cross sections of polycrystalline thin films. In this work, we apply a modification of AFM, namely, electrostatic force microscopy (EFM), to investigate the electronic properties of cleaved II--VI and multijunction thin-film solar cells. We cleave the devices in such a way that they are still working with their nominal photovoltaic efficiencies and can be polarized for the measurements. This allows us to differentiate between surface effects (work function and surface band bending) and bulk device properties. In the case of polycrystalline CdTe/CdS/SnO{sub 2}/glass solar cells, we find a drop of the EFM signal in the area of the CdTe/CdS interface ({+-}50 nm). This drop varies in amplitude and sign according to the applied external bias and is compatible with an n-CdS/p-CdTe heterojunction model, thereby invalidating the possibility of a deeply buried n-p CdTe homojunction. In the case of a triple-junction GaInP/GaAs/Ge device, we observe a variation of the EFM signal linked to both the material work-function differences and to the voltage bias applied to the cell. We attempt a qualitative explanation of the results and discuss the implications and difficulties of the EFM technique for the study of such thin-film devices.

  13. Spatially resolved determination of the short-circuit current density of silicon solar cells via lock-in thermography

    SciTech Connect (OSTI)

    Fertig, Fabian Greulich, Johannes; Rein, Stefan

    2014-05-19

    We present a spatially resolved method to determine the short-circuit current density of crystalline silicon solar cells by means of lock-in thermography. The method utilizes the property of crystalline silicon solar cells that the short-circuit current does not differ significantly from the illuminated current under moderate reverse bias. Since lock-in thermography images locally dissipated power density, this information is exploited to extract values of spatially resolved current density under short-circuit conditions. In order to obtain an accurate result, one or two illuminated lock-in thermography images and one dark lock-in thermography image need to be recorded. The method can be simplified in a way that only one image is required to generate a meaningful short-circuit current density map. The proposed method is theoretically motivated, and experimentally validated for monochromatic illumination in comparison to the reference method of light-beam induced current.

  14. Well-Passivated a-Si:H Back Contacts for Double-Heterojunction Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Page, M. R.; Iwaniczko, E.; Xu, Y.; Wang, Q.; Yan, Y.; Roybal, L.; Branz, H. M.; Wang, T. H.

    2006-05-01

    We have developed hydrogenated amorphous silicon (a Si:H) back contacts to both p- and n-type silicon wafers, and employed them in double-heterojunction solar cells. These contacts are deposited entirely at low temperature (<250 C) and replace the standard diffused or alloyed back-surface-field contacts used in single-heterojunction (front-emitter only) cells. High-quality back contacts require excellent surface passivation, indicated by a low surface recombination velocity of minority-carriers (S) or a high open-circuit voltage (Voc). The back contact must also provide good conduction for majority carriers to the external circuit, as indicated by a high light I-V fill factor. We use hot-wire chemical vapor deposition (HWCVD) to grow a-Si:H layers for both the front emitters and back contacts. Our improved a-Si:H back contacts contribute to our recent achievement of a confirmed 18.2% efficiency in double-heterojunction silicon solar cells on p type textured silicon wafers.

  15. Longwei Silicon Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Silicon Co Ltd Place: Liancheng, Fujian Province, China Sector: Solar Product: A Chinese sillicon metal producer who also produce 4N-6N silicon for solar use. Coordinates:...

  16. Low-temperature high-mobility amorphous IZO for silicon heterojunction solar cells

    SciTech Connect (OSTI)

    Morales-Masis, Monica; Martin De Nicolas, Silvia; Holovsky, Jakub; De Wolf, Stefaan; Ballif, Christophe

    2015-07-13

    Parasitic absorption in the transparent conductive oxide (TCO) front electrode is one of the limitations of silicon heterojunction (SHJ) solar cells efficiency. To avoid such absorption while retaining high conductivity, TCOs with high electron mobility are preferred over those with high carrier density. Here, we demonstrate improved SHJ solar cell efficiencies by applying high-mobility amorphous indium zinc oxide (a-IZO) as the front TCO. We sputtered a-IZO at low substrate temperature and low power density and investigated the optical and electrical properties, as well as subband tail formation-quantified by the Urbach energy (EU)-as a function of the sputtering oxygen partial pressure. We obtain an EU as low as 128 meV for films with the highest Hall mobility of 60 cm2/Vs. When comparing the performance of a-IZO films with indium tin oxide (ITO) and hydrogenated indium oxide (IO:H), we find that IO:H (115 cm2/Vs) exhibits a similar EU of 130 meV, while ITO (25 cm2/Vs) presents a much larger EU of up to 270 meV. The high film quality, indicated by the low EU, the high mobility, and low free carrier absorption of the developed a-IZO electrodes, result in a significant current improvement, achieving conversion efficiencies over 21.5%, outperforming those with standard ITO.

  17. NREL's Black Silicon Increases Solar Cell Efficiency by Reducing Reflected Sunlight (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-11-01

    A fact sheet detailing the R&D 100 Award-winning Black Silicon Nanocatalytic Wet-Chemical Etch technology.

  18. Characterization of Epitaxial Film Silicon Solar Cells Grown on Seeded Display Glass: Preprint

    SciTech Connect (OSTI)

    Young, D. L.; Grover, S.; Teplin, C.; Stradins, P.; LaSalvia, V.; Chuang, T. K.; Couillard, J. G.; Branz, H. M.

    2012-06-01

    We report characterizations of epitaxial film crystal silicon (c-Si) solar cells with open-circuit voltages (Voc) above 560 mV. The 2-um absorber cells are grown by low-temperature (<750 degrees C) hot-wire CVD (HWCVD) on Corning EAGLE XG display glass coated with a layer-transferred (LT) Si seed. The high Voc is a result of low-defect epitaxial Si (epi-Si) growth and effective hydrogen passivation of defects. The quality of HWCVD epitaxial growth on seeded glass substrates depends on the crystallographic quality of the seed and the morphology of the epitaxial growth surface. Heterojunction devices consist of glass/c-Si LT seed/ epi n+ Si:P/epi n- Si:P/intrinsic a-Si:H/p+ a-Si:H/ITO. Similar devices grown on electronically 'dead' n+ wafers have given Voc {approx}630 mV and {approx}8% efficiency with no light trapping features. Here we study the effects of the seed surface polish on epi-Si quality, how hydrogenation influences the device character, and the dominant junction transport physics.

  19. Electric properties and carrier multiplication in breakdown sites in multi-crystalline silicon solar cells

    SciTech Connect (OSTI)

    Schneemann, Matthias; Carius, Reinhard; Rau, Uwe; Kirchartz, Thomas

    2015-05-28

    This paper studies the effective electrical size and carrier multiplication of breakdown sites in multi-crystalline silicon solar cells. The local series resistance limits the current of each breakdown site and is thereby linearizing the current-voltage characteristic. This fact allows the estimation of the effective electrical diameters to be as low as 100?nm. Using a laser beam induced current (LBIC) measurement with a high spatial resolution, we find carrier multiplication factors on the order of 30 (Zener-type breakdown) and 100 (avalanche breakdown) as new lower limits. Hence, we prove that also the so-called Zener-type breakdown is followed by avalanche multiplication. We explain that previous measurements of the carrier multiplication using thermography yield results higher than unity, only if the spatial defect density is high enough, and the illumination intensity is lower than what was used for the LBIC method. The individual series resistances of the breakdown sites limit the current through these breakdown sites. Therefore, the measured multiplication factors depend on the applied voltage as well as on the injected photocurrent. Both dependencies are successfully simulated using a series-resistance-limited diode model.

  20. Generation of low work function, stable compound thin films by laser ablation

    DOE Patents [OSTI]

    Dinh, Long N. (Concord, CA); McLean, II, William (Oakland, CA); Balooch, Mehdi (Berkeley, CA); Fehring, Jr., Edward J. (Dublin, CA); Schildbach, Marcus A. (Livermore, CA)

    2001-01-01

    Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

  1. InGaN-based thin film solar cells: Epitaxy, structural design, and photovoltaic properties

    SciTech Connect (OSTI)

    Sang, Liwen; Liao, Meiyong; Koide, Yasuo; Sumiya, Masatomo

    2015-03-14

    In{sub x}Ga{sub 1?x}N, with the tunable direct bandgaps from ultraviolet to near infrared region, offers a promising candidate for the high-efficiency next-generation thin-film photovoltaic applications. Although the adoption of thick InGaN film as the active region is desirable to obtain efficient light absorption and carrier collection compared to InGaN/GaN quantum wells structure, the understanding on the effect from structural design is still unclear due to the poor-quality InGaN films with thickness and difficulty of p-type doping. In this paper, we comprehensively investigate the effects from film epitaxy, doping, and device structural design on the performances of the InGaN-based solar cells. The high-quality InGaN thick film is obtained on AlN/sapphire template, and p-In{sub 0.08}Ga{sub 0.92}N is achieved with a high hole concentration of more than 10{sup 18?}cm{sup ?3}. The dependence of the photovoltaic performances on different structures, such as active regions and p-type regions is analyzed with respect to the carrier transport mechanism in the dark and under illumination. The strategy of improving the p-i interface by using a super-thin AlN interlayer is provided, which successfully enhances the performance of the solar cells.

  2. Forming high-efficiency silicon solar cells using density-graded anti-reflection surfaces

    DOE Patents [OSTI]

    Yuan, Hao-Chih; Branz, Howard M.; Page, Matthew R.

    2015-07-07

    A method (50) is provided for processing a graded-density AR silicon surface (14) to provide effective surface passivation. The method (50) includes positioning a substrate or wafer (12) with a silicon surface (14) in a reaction or processing chamber (42). The silicon surface (14) has been processed (52) to be an AR surface with a density gradient or region of black silicon. The method (50) continues with heating (54) the chamber (42) to a high temperature for both doping and surface passivation. The method (50) includes forming (58), with a dopant-containing precursor in contact with the silicon surface (14) of the substrate (12), an emitter junction (16) proximate to the silicon surface (14) by doping the substrate (12). The method (50) further includes, while the chamber is maintained at the high or raised temperature, forming (62) a passivation layer (19) on the graded-density silicon anti-reflection surface (14).

  3. Forming high efficiency silicon solar cells using density-graded anti-reflection surfaces

    DOE Patents [OSTI]

    Yuan, Hao-Chih; Branz, Howard M.; Page, Matthew R.

    2014-09-09

    A method (50) is provided for processing a graded-density AR silicon surface (14) to provide effective surface passivation. The method (50) includes positioning a substrate or wafer (12) with a silicon surface (14) in a reaction or processing chamber (42). The silicon surface (14) has been processed (52) to be an AR surface with a density gradient or region of black silicon. The method (50) continues with heating (54) the chamber (42) to a high temperature for both doping and surface passivation. The method (50) includes forming (58), with a dopant-containing precursor in contact with the silicon surface (14) of the substrate (12), an emitter junction (16) proximate to the silicon surface (14) by doping the substrate (12). The method (50) further includes, while the chamber is maintained at the high or raised temperature, forming (62) a passivation layer (19) on the graded-density silicon anti-reflection surface (14).

  4. Reliable wet-chemical cleaning of natively oxidized high-efficiency Cu(In,Ga)Se{sub 2} thin-film solar cell absorbers

    SciTech Connect (OSTI)

    Lehmann, Jascha; Lehmann, Sebastian; Lauermann, Iver; Rissom, Thorsten; Kaufmann, Christian A.; Lux-Steiner, Martha Ch.; Br, Marcus; Sadewasser, Sascha

    2014-12-21

    Currently, Cu-containing chalcopyrite-based solar cells provide the highest conversion efficiencies among all thin-film photovoltaic (PV) technologies. They have reached efficiency values above 20%, the same performance level as multi-crystalline silicon-wafer technology that dominates the commercial PV market. Chalcopyrite thin-film heterostructures consist of a layer stack with a variety of interfaces between different materials. It is the chalcopyrite/buffer region (forming the p-n junction), which is of crucial importance and therefore frequently investigated using surface and interface science tools, such as photoelectron spectroscopy and scanning probe microscopy. To ensure comparability and validity of the results, a general preparation guide for realistic surfaces of polycrystalline chalcopyrite thin films is highly desirable. We present results on wet-chemical cleaning procedures of polycrystalline Cu(In{sub 1-x}Ga{sub x})Se{sub 2} thin films with an average x?=?[Ga]/([In]?+?[Ga])?=?0.29, which were exposed to ambient conditions for different times. The hence natively oxidized sample surfaces were etched in KCN- or NH{sub 3}-based aqueous solutions. By x-ray photoelectron spectroscopy, we find that the KCN treatment results in a chemical surface structure which is apart from a slight change in surface composition identical to a pristine as-received sample surface. Additionally, we discover a different oxidation behavior of In and Ga, in agreement with thermodynamic reference data, and we find indications for the segregation and removal of copper selenide surface phases from the polycrystalline material.

  5. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    thin, MEMS contact-stress sensor continuously and accurately measures time-varying, solid interface loads over tens of thousands of load cycles. The contact-stress sensor is extremely thin (150 {mu}m) and has a linear output with an accuracy of {+-} 1.5% FSO. Authors: Kotovksy, J ; Tooker, A ; Horsley, D Publication Date: 2010-05-28 OSTI Identifier: 984646 Report Number(s): LLNL-PROC-433955 TRN: US201016%%1413 DOE Contract Number: W-7405-ENG-48 Resource Type: Conference Resource Relation:

  6. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    thin, MEMS contact-stress sensor continuously and accurately measures time-varying, solid interface loads over tens of thousands of load cycles. The contact-stress sensor is extremely thin (150 {mu}m) and has a linear output with an accuracy of {+-} 1.5% FSO. Authors: Kotovksy, J ; Tooker, A ; Horsley, D Publication Date: 2010-05-28 OSTI Identifier: 984646 Report Number(s): LLNL-PROC-433955 TRN: US201016%%1413 DOE Contract Number: W-7405-ENG-48 Resource Type: Conference Resource Relation:

  7. Thin Silicon MEMS Contact-Stress Sensor (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    thin, MEMS contact-stress sensor continuously and accurately measures time-varying, solid interface loads over tens of thousands of load cycles. The contact-stress sensor is extremely thin (150 {mu}m) and has a linear output with an accuracy of {+-} 1.5% FSO. Authors: Kotovksy, J ; Tooker, A ; Horsley, D Publication Date: 2010-05-28 OSTI Identifier: 984646 Report Number(s): LLNL-PROC-433955 TRN: US201016%%1413 DOE Contract Number: W-7405-ENG-48 Resource Type: Conference Resource Relation:

  8. New Metallization Technique Suitable for 6-MW Pilot Production of Efficient Multicrystalline Solar Cells Using Upgraded Metallurgical Silicon: Final Technical Progress Report, December 17, 2007 -- June 16, 2009

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Subcontract Report NREL/SR-520-48591 August 2010 New Metallization Technique Suitable for 6-MW Pilot Production of Efficient Multicrystalline Solar Cells Using Upgraded Metallurgical Silicon Final Technical Progress Report December 17, 2007 - June 16, 2009 K. Ounadjela and A. Blosse CaliSolar, Inc. Sunnyvale, California A Project Funded under the U.S. DOE Solar Energy Technologies Program's Photovoltaic Technology Incubator National Renewable Energy Laboratory 1617 Cole Boulevard, Golden,

  9. Toward a Monolithic Lattice-Matched III-V on Silicon Tandem Solar Cell

    SciTech Connect (OSTI)

    Geisz, J. F.; Olson, J. M.; Friedman, D. J.

    2004-09-01

    A two-junction device consisting of a 1.7-eV GaNPAs junction on a 1.1-eV silicon junction has the theoretical potential to achieve nearly optimal efficiency for a two-junction tandem cell. We have demonstrated some of the key components toward realizing such a cell, including GaNPAs top cells grown on silicon substrates, GaP-based tunnel junctions grown on silicon substrates, and diffused silicon junctions formed during the epitaxial growth of GaNP on silicon. These components have required the development of techniques for the growth of high crystalline quality GaNPAs on silicon by metal-organic vapor-phase epitaxy.

  10. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

    1995-11-14

    Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

  11. Solar cell array interconnects

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA); Colella, Nicolas J. (Livermore, CA); Williams, Kenneth A. (Livermore, CA)

    1995-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  12. High Volume Manufacturing of Silicon-Film Solar Cells and Modules; Final Subcontract Report, 26 February 2003 - 30 September 2003

    SciTech Connect (OSTI)

    Rand, J. A.; Culik, J. S.

    2005-10-01

    The objective of the PV Manufacturing R&D subcontract was to continue to improve AstroPower's technology for manufacturing Silicon-Film* wafers, solar cells, and modules to reduce costs, and increase production yield, throughput, and capacity. As part of the effort, new technology such as the continuous back metallization screen-printing system and the laser scribing system were developed and implemented. Existing processes, such as the silicon nitride antireflection coating system and the fire-through process were optimized. Improvements were made to the statistical process control (SPC) systems of the major manufacturing processes: feedstock preparation, wafer growth, surface etch, diffusion, and the antireflection coating process. These process improvements and improved process control have led to an increase of 5% relative power, and nearly 15% relative improvement in mechanical and visual yield.

  13. Application of ITO/Al reflectors for increasing the efficiency of single-crystal silicon solar cells

    SciTech Connect (OSTI)

    Kopach, V. R.; Kirichenko, M. V. Khrypunov, G. S.; Zaitsev, R. V.

    2010-06-15

    It is shown that an increase in the efficiency and manufacturability of single-junction single-crystal silicon photoelectric converters of solar energy requires the use of a back-surface reflector based on conductive transparent indium-tin oxide (ITO) 0.25-2 {mu}m thick. To increase the efficiency and reduce the sensitivity to the angle of light incidence on the photoreceiving surface of multijunction photoelectric converters with vertical diode cells based on single-crystal silicon, ITO/Al reflectors with an ITO layer >1 {mu}m thick along vertical boundaries of diode cells should be fabricated. The experimental study of multijunction photoelectric converters with ITO/Al reflectors at diode cell boundaries shows the necessity of modernizing the used technology of ITO layers to achieve their theoretically calculated thickness.

  14. Advanced processing technology for high-efficiency, thin-film CuInSe{sub 2} and CdTe solar cells. Annual subcontract report, 1 March 1993--28 February 1994

    SciTech Connect (OSTI)

    Morel, D.L.; Ferekides, C.S.

    1994-07-01

    This annual report details activities in research on advanced processing technology for high-effiency, thin-film solar cells.

  15. Methods for forming thin-film heterojunction solar cells from I-III-VI[sub 2

    DOE Patents [OSTI]

    Mickelsen, R.A.; Chen, W.S.

    1982-06-15

    An improved thin-film, large area solar cell, and methods for forming the same are disclosed, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (1) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI[sub 2] chalcopyrite ternary materials which is vacuum deposited in a thin composition-graded'' layer ranging from on the order of about 2.5 microns to about 5.0 microns ([approx equal]2.5[mu]m to [approx equal]5.0[mu]m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (2), a second semiconductor layer comprising a low resistivity n-type semiconductor material; wherein interdiffusion (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer, is allowed.

  16. Methods for forming thin-film heterojunction solar cells from I-III-VI{sub 2}

    DOE Patents [OSTI]

    Mickelsen, R.A.; Chen, W.S.

    1985-08-13

    An improved thin-film, large area solar cell, and methods for forming the same are disclosed, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI{sub 2} chalcopyrite ternary materials which is vacuum deposited in a thin ``composition-graded`` layer ranging from on the order of about 2.5 microns to about 5.0 microns ({approx_equal}2.5 {mu}m to {approx_equal}5.0 {mu}m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (ii) a second semiconductor layer comprising a low resistivity n-type semiconductor material; wherein interdiffusion occurs (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer. 16 figs.

  17. Methods for forming thin-film heterojunction solar cells from I-III-VI.sub. 2

    DOE Patents [OSTI]

    Mickelsen, Reid A.; Chen, Wen S.

    1985-08-13

    An improved thin-film, large area solar cell, and methods for forming the same, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI.sub.2 chalcopyrite ternary materials which is vacuum deposited in a thin "composition-graded" layer ranging from on the order ot about 2.5 microns to about 5.0 microns (.congruent.2.5 .mu.m to .congruent.5.0 .mu.m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (ii), a second semiconductor layer comprising a low resistivity n-type semiconductor material; wherein interdiffusion (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer, causes the The Government has rights in this invention pursuant to Contract No. EG-77-C-01-4042, Subcontract No. XJ-9-8021-1 awarded by the U.S. Department of Energy.

  18. Methods for forming thin-film heterojunction solar cells from I-III-VI.sub. 2

    DOE Patents [OSTI]

    Mickelsen, Reid A. (Bellevue, WA); Chen, Wen S. (Seattle, WA)

    1982-01-01

    An improved thin-film, large area solar cell, and methods for forming the same, having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI.sub.2 chalcopyrite ternary materials which is vacuum deposited in a thin "composition-graded" layer ranging from on the order of about 2.5 microns to about 5.0 microns (.congruent.2.5.mu.m to .congruent.5.0.mu.m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (ii), a second semiconductor layer comprising a low resistivity n-type semiconductor material; wherein interdiffusion (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer, causes the transient n-type material in The Government has rights in this invention pursuant to Contract No. EG-77-C-01-4042, Subcontract No. XJ-9-8021-1 awarded by the U.S. Department of Energy.

  19. 18th Workshop on Crystalline Silicon Solar Cells and Modules: Materials and Processes; Workshop Proceedings, 3-6 August 2008, Vail, Colorado

    SciTech Connect (OSTI)

    Sopori, B. L.

    2008-09-01

    The National Center for Photovoltaics sponsored the 18th Workshop on Crystalline Silicon Solar Cells & Modules: Materials and Processes, held in Vail, CO, August 3-6, 2008. This meeting provided a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. The theme of this year's meeting was 'New Directions for Rapidly Growing Silicon Technologies.'

  20. Has sempra found El Dorado in solar PVs? grid parity may now be within reach

    SciTech Connect (OSTI)

    2009-03-15

    Instead of using conventional polycrystalline silicon modules that turn sunlight into electricity, these solar panels use cadmium telluride, a lower-cost semiconductor manufactured into thin-film cells that are cheaper to manufacture than their silicon-based counterparts. Electricity is being produced at costs as low as 7.5 {cents}/kWh.

  1. Back-junction back-contact n-type silicon solar cell with diffused boron emitter locally blocked by implanted phosphorus

    SciTech Connect (OSTI)

    Mller, Ralph Schrof, Julian; Reichel, Christian; Benick, Jan; Hermle, Martin

    2014-09-08

    The highest energy conversion efficiencies in the field of silicon-based photovoltaics have been achieved with back-junction back-contact (BJBC) silicon solar cells by several companies and research groups. One of the most complex parts of this cell structure is the fabrication of the locally doped p- and n-type regions, both on the back side of the solar cell. In this work, we introduce a process sequence based on a synergistic use of ion implantation and furnace diffusion. This sequence enables the formation of all doped regions for a BJBC silicon solar cell in only three processing steps. We observed that implanted phosphorus can block the diffusion of boron atoms into the silicon substrate by nearly three orders of magnitude. Thus, locally implanted phosphorus can be used as an in-situ mask for a subsequent boron diffusion which simultaneously anneals the implanted phosphorus and forms the boron emitter. BJBC silicon solar cells produced with such an easy-to-fabricate process achieved conversion efficiencies of up to 21.7%. An open-circuit voltage of 674?mV and a fill factor of 80.6% prove that there is no significant recombination at the sharp transition between the highly doped emitter and the highly doped back surface field at the device level.

  2. Evaluation of Solar Grade Silicon Produced by the Institute of Physics and Technology: Cooperative Research and Development Final Report, CRADA Number CRD-07-211

    SciTech Connect (OSTI)

    Page, M.

    2013-02-01

    NREL and Solar Power Industries will cooperate to evaluate technology for producing solar grade silicon from industrial waste of the phosphorus industry, as developed by the Institute of Physics and Technology (IPT), Kazakhstan. Evaluation will have a technical component to assess the material quality and a business component to assess the economics of the IPT process. The total amount of silicon produced by IPT is expected to be quite limited (50 kg), so evaluations will need to be done on relatively small quantities (? 5 kg/sample).

  3. 17.1%-Efficient Multi-Scale-Textured Black Silicon Solar Cells without Dielectric Antireflection Coating: Preprint

    SciTech Connect (OSTI)

    Toor, F.; Page, M. R.; Branz, H. M.; Yuan, H. C.

    2011-07-01

    In this work we present 17.1%-efficient p-type single crystal Si solar cells with a multi-scale-textured surface and no dielectric antireflection coating. Multi-scale texturing is achieved by a gold-nanoparticle-assisted nanoporous etch after conventional micron scale KOH-based pyramid texturing (pyramid black etching). By incorporating geometric enhancement of antireflection, this multi-scale texturing reduces the nanoporosity depth required to make silicon 'black' compared to nanoporous planar surfaces. As a result, it improves short-wavelength spectral response (blue response), previously one of the major limiting factors in 'black-Si' solar cells. With multi-scale texturing, the spectrum-weighted average reflectance from 350- to 1000-nm wavelength is below 2% with a 100-nm deep nanoporous layer. In comparison, roughly 250-nm deep nanopores are needed to achieve similar reflectance on planar surface. Here, we characterize surface morphology, reflectivity and solar cell performance of the multi-scale textured solar cells.

  4. ENHANCED GROWTH RATE AND SILANE UTILIZATION IN AMORPHOUS SILICON AND NANOCRYSTALLINE-SILICON SOLAR CELL DEPOSITION VIA GAS PHASE ADDITIVES

    SciTech Connect (OSTI)

    Ridgeway, R.G.; Hegedus, S.S.; Podraza, N.J.

    2012-08-31

    Air Products set out to investigate the impact of additives on the deposition rate of both ???µCSi and ???±Si-H films. One criterion for additives was that they could be used in conventional PECVD processing, which would require sufficient vapor pressure to deliver material to the process chamber at the required flow rates. The flow rate required would depend on the size of the substrate onto which silicon films were being deposited, potentially ranging from 200 mm diameter wafers to the 5.7 m2 glass substrates used in GEN 8.5 flat-panel display tools. In choosing higher-order silanes, both disilane and trisilane had sufficient vapor pressure to withdraw gas at the required flow rates of up to 120 sccm. This report presents results obtained from testing at Air Products?¢???? electronic technology laboratories, located in Allentown, PA, which focused on developing processes on a commercial IC reactor using silane and mixtures of silane plus additives. These processes were deployed to compare deposition rates and film properties with and without additives, with a goal of maximizing the deposition rate while maintaining or improving film properties.

  5. The Effect of High Temperature Annealing on the Grain Characteristics of a Thin Chemical Vapor Deposition Silicon Carbide Layer.

    SciTech Connect (OSTI)

    Isabella J van Rooyen; Philippus M van Rooyen; Mary Lou Dunzik-Gougar

    2013-08-01

    The unique combination of thermo-mechanical and physiochemical properties of silicon carbide (SiC) provides interest and opportunity for its use in nuclear applications. One of the applications of SiC is as a very thin layer in the TRi-ISOtropic (TRISO) coated fuel particles for high temperature gas reactors (HTGRs). This SiC layer, produced by chemical vapor deposition (CVD), is designed to withstand the pressures of fission and transmutation product gases in a high temperature, radiation environment. Various researchers have demonstrated that macroscopic properties can be affected by changes in the distribution of grain boundary plane orientations and misorientations [1 - 3]. Additionally, various researchers have attributed the release behavior of Ag through the SiC layer as a grain boundary diffusion phenomenon [4 - 6]; further highlighting the importance of understanding the actual grain characteristics of the SiC layer. Both historic HTGR fission product release studies and recent experiments at Idaho National Laboratory (INL) [7] have shown that the release of Ag-110m is strongly temperature dependent. Although the maximum normal operating fuel temperature of a HTGR design is in the range of 1000-1250C, the temperature may reach 1600C under postulated accident conditions. The aim of this specific study is therefore to determine the magnitude of temperature dependence on SiC grain characteristics, expanding upon initial studies by Van Rooyen et al, [8; 9].

  6. Hexagon solar power panel

    DOE Patents [OSTI]

    Rubin, Irwin (Oxnard, CA)

    1978-01-01

    A solar energy panel comprises a support upon which silicon cells are arrayed. The cells are wafer thin and of two geometrical types, both of the same area and electrical rating, namely hexagon cells and hourglass cells. The hourglass cells are composites of half hexagons. A near perfect nesting relationship of the cells achieves a high density packing whereby optimum energy production per panel area is achieved.

  7. Washington Silicon Plant Makes Way for Cheaper Solar-and Jobs...

    Office of Environmental Management (EM)

    "This ground-breaking technology demonstrates the advantages of scaled-up designs and more energy-efficient production, making solar energy a more affordable alternative," Ekern ...

  8. Low-Cost Light Weigh Thin Film Solar Concentrators | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    313_ganapathi.pdf More Documents & Publications Low-Cost, Lightweight Solar Concentrators - FY13 Q1 Low-Cost, Lightweight Solar Concentrators FY13 Q2

  9. Short-circuit current density imaging of crystalline silicon solar cells via lock-in thermography: Robustness and simplifications

    SciTech Connect (OSTI)

    Fertig, Fabian Greulich, Johannes; Rein, Stefan

    2014-11-14

    Spatially resolved determination of solar cell parameters is beneficial for loss analysis and optimization of conversion efficiency. One key parameter that has been challenging to access by an imaging technique on solar cell level is short-circuit current density. This work discusses the robustness of a recently suggested approach to determine short-circuit current density spatially resolved based on a series of lock-in thermography images and options for a simplified image acquisition procedure. For an accurate result, one or two emissivity-corrected illuminated lock-in thermography images and one dark lock-in thermography image have to be recorded. The dark lock-in thermography image can be omitted if local shunts are negligible. Furthermore, it is shown that omitting the correction of lock-in thermography images for local emissivity variations only leads to minor distortions for standard silicon solar cells. Hence, adequate acquisition of one image only is sufficient to generate a meaningful map of short-circuit current density. Beyond that, this work illustrates the underlying physics of the recently proposed method and demonstrates its robustness concerning varying excitation conditions and locally increased series resistance. Experimentally gained short-circuit current density images are validated for monochromatic illumination in comparison to the reference method of light-beam induced current.

  10. Producing Solar Cells By Surface Preparation For Accelerated Nucleation Of Microcrystalline Silicon On Heterogeneous Substrates.

    DOE Patents [OSTI]

    Yang, Liyou; Chen, Liangfan

    1998-03-24

    Attractive multi-junction solar cells and single junction solar cells with excellent conversion efficiency can be produced with a microcrystalline tunnel junction, microcrystalline recombination junction or one or more microcrystalline doped layers by special plasma deposition processes which includes plasma etching with only hydrogen or other specified etchants to enhance microcrystalline growth followed by microcrystalline. nucleation with a doped hydrogen-diluted feedstock.

  11. Pulsed energy synthesis and doping of silicon carbide

    DOE Patents [OSTI]

    Truher, J.B.; Kaschmitter, J.L.; Thompson, J.B.; Sigmon, T.W.

    1995-06-20

    A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate is disclosed, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27--730 C is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including HETEROJUNCTION-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

  12. Pulsed energy synthesis and doping of silicon carbide

    DOE Patents [OSTI]

    Truher, Joel B. (San Rafael, CA); Kaschmitter, James L. (Pleasanton, CA); Thompson, Jesse B. (Brentwood, CA); Sigmon, Thomas W. (Beaverton, OR)

    1995-01-01

    A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27.degree.-730.degree. C. is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including hetero-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

  13. Back-side hydrogenation technique for defect passivation in silicon solar cells

    DOE Patents [OSTI]

    Sopori, B.L.

    1994-04-19

    A two-step back-side hydrogenation process includes the steps of first bombarding the back side of the silicon substrate with hydrogen ions with intensities and for a time sufficient to implant enough hydrogen atoms into the silicon substrate to potentially passivate substantially all of the defects and impurities in the silicon substrate, and then illuminating the silicon substrate with electromagnetic radiation to activate the implanted hydrogen, so that it can passivate the defects and impurities in the substrate. The illumination step also annihilates the hydrogen-induced defects. The illumination step is carried out according to a two-stage illumination schedule, the first or low-power stage of which subjects the substrate to electromagnetic radiation that has sufficient intensity to activate the implanted hydrogen, yet not drive the hydrogen from the substrate. The second or high-power illumination stage subjects the substrate to higher intensity electromagnetic radiation, which is sufficient to annihilate the hydrogen-induced defects and sinter/alloy the metal contacts. 3 figures.

  14. Back-side hydrogenation technique for defect passivation in silicon solar cells

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO)

    1994-01-01

    A two-step back-side hydrogenation process includes the steps of first bombarding the back side of the silicon substrate with hydrogen ions with intensities and for a time sufficient to implant enough hydrogen atoms into the silicon substrate to potentially passivate substantially all of the defects and impurities in the silicon substrate, and then illuminating the silicon substrate with electromagnetic radiation to activate the implanted hydrogen, so that it can passivate the defects and impurities in the substrate. The illumination step also annihilates the hydrogen-induced defects. The illumination step is carried out according to a two-stage illumination schedule, the first or low-power stage of which subjects the substrate to electromagnetic radiation that has sufficient intensity to activate the implanted hydrogen, yet not drive the hydrogen from the substrate. The second or high-power illumination stage subjects the substrate to higher intensity electromagnetic radiation, which is sufficient to annihilate the hydrogen-induced defects and sinter/alloy the metal contacts.

  15. Method for cleaning a solar cell surface opening made with a solar etch paste

    DOE Patents [OSTI]

    Rohatgi, Ajeet; Meemongkolkiat, Vichai

    2010-06-22

    A thin silicon solar cell having a back dielectric passivation and rear contact with local back surface field is described. Specifically, the solar cell may be fabricated from a crystalline silicon wafer having a thickness from 50 to 500 micrometers. A barrier layer and a dielectric layer are applied at least to the back surface of the silicon wafer to protect the silicon wafer from deformation when the rear contact is formed. At least one opening is made to the dielectric layer. An aluminum contact that provides a back surface field is formed in the opening and on the dielectric layer. The aluminum contact may be applied by screen printing an aluminum paste having from one to 12 atomic percent silicon and then applying a heat treatment at 750 degrees Celsius.

  16. Optimization of transparent and reflecting electrodes for amorphous silicon solar cells. Annual subcontract report, April 1, 1994--March 31, 1995

    SciTech Connect (OSTI)

    Gordon, R.G.

    1995-10-01

    Transparent and reflecting electrodes are important parts of the structure of amorphous silicon solar cells. We report improved methods for depositing zinc oxide, deposition of tin nitride as a potential reflection-enhancing diffusion barrier between the a-Si and back metal electrodes. Highly conductive and transparent fluorine-doped zinc oxide was successfully produced on small areas by atmospheric pressure CVD from a less hazardous zinc precursor, zinc acetylacetonate. The optical properties measured for tin nitride showed that the back-reflection would be decreased if tin nitride were used instead of zinc oxide as a barrier layer over silver on aluminum. Niobium-doped titanium dioxide was produced with high enough electrical conductivity so that normal voltages and fill factors were obtained for a-Si cells made on it.

  17. Potential-induced degradation in solar cells: Electronic structure and diffusion mechanism of sodium in stacking faults of silicon

    SciTech Connect (OSTI)

    Ziebarth, Benedikt Gumbsch, Peter; Mrovec, Matous; Elssser, Christian

    2014-09-07

    Sodium decorated stacking faults (SFs) were recently identified as the primary cause of potential-induced degradation in silicon (Si) solar-cells due to local electrical short-circuiting of the p-n junctions. In the present study, we investigate these defects by first principles calculations based on density functional theory in order to elucidate their structural, thermodynamic, and electronic properties. Our calculations show that the presence of sodium (Na) atoms leads to a substantial elongation of the Si-Si bonds across the SF, and the coverage and continuity of the Na layer strongly affect the diffusion behavior of Na within the SF. An analysis of the electronic structure reveals that the presence of Na in the SF gives rise to partially occupied defect levels within the Si band gap that participate in electrical conduction along the SF.

  18. Determination of defect density of state distribution of amorphous silicon solar cells by temperature derivative capacitance-frequency measurement

    SciTech Connect (OSTI)

    Yang, Guangtao Swaaij, R. A. C. M. M. van; Dobrovolskiy, S.; Zeman, M.

    2014-01-21

    In this contribution, we demonstrate the application temperature dependent capacitance-frequency measurements (C-f) to n-i-p hydrogenated amorphous silicon (a-Si:H) solar cells that are forward-biased. By using a forward bias, the C-f measurement can detect the density of defect states in a particular energy range of the interface region. For this contribution, we have carried out this measurement method on n-i-p a-Si:H solar cells of which the intrinsic layer has been exposed to a H{sub 2}-plasma before p-type layer deposition. After this treatment, the open-circuit voltage and fill factor increased significantly, as well as the blue response of the solar cells as is concluded from external quantum efficiency. For single junction, n-i-p a-Si:H solar cells initial efficiency increased from 6.34% to 8.41%. This performance enhancement is believed to be mainly due to a reduction of the defect density in the i-p interface region after the H{sub 2}-plasma treatment. These results are confirmed by the C-f measurements. After H{sub 2}-plasma treatment, the defect density in the intrinsic layer near the i-p interface region is lower and peaks at an energy level deeper in the band gap. These C-f measurements therefore enable us to monitor changes in the defect density in the interface region as a result of a hydrogen plasma. The lower defect density at the i-p interface as detected by the C-f measurements is supported by dark current-voltage measurements, which indicate a lower carrier recombination rate.

  19. Crystal Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc Jump to: navigation, search Name: Crystal Solar Inc. Place: Santa Clara, California Zip: 94054 Sector: Solar Product: California-based developer of silicon solar cells....

  20. Enhanced efficiency of graphene-silicon Schottky junction solar cells by doping with Au nanoparticles

    SciTech Connect (OSTI)

    Liu, X.; Zhang, X. W. Yin, Z. G.; Meng, J. H.; Gao, H. L.; Zhang, L. Q.; Zhao, Y. J.; Wang, H. L.

    2014-11-03

    We have reported a method to enhance the performance of graphene-Si (Gr/Si) Schottky junction solar cells by introducing Au nanoparticles (NPs) onto the monolayer graphene and few-layer graphene. The electron transfer between Au NPs and graphene leads to the increased work function and enhanced electrical conductivity of graphene, resulting in a remarkable improvement of device efficiency. By optimizing the initial thickness of Au layers, the power conversion efficiency of Gr/Si solar cells can be increased by more than three times, with a maximum value of 7.34%. These results show a route for fabricating efficient and stable Gr/Si solar cells.

  1. Temperature-Dependent Photoluminescence Imaging and Characterization of a Multi-Crystalline Silicon Solar Cell Defect Area: Preprint

    SciTech Connect (OSTI)

    Johnston, S.; Yan, F.; Li, J.; Romero, M. J.; Al-Jassim, M.; Zaunbrecher, K.; Sidelkheir, O.; Blosse, A.

    2011-07-01

    Photoluminescence (PL) imaging is used to detect areas in multi-crystalline silicon that appear dark in band-to-band imaging due to high recombination. Steady-state PL intensity can be correlated to effective minority-carrier lifetime, and its temperature dependence can provide additional lifetime-limiting defect information. An area of high defect density has been laser cut from a multi-crystalline silicon solar cell. Both band-to-band and defect-band PL imaging have been collected as a function of temperature from ~85 to 350 K. Band-to-band luminescence is collected by an InGaAs camera using a 1200-nm short-pass filter, while defect band luminescence is collected using a 1350-nm long pass filter. The defect band luminescence is characterized by cathodo-luminescence. Small pieces from adjacent areas within the same wafer are measured by deep-level transient spectroscopy (DLTS). DLTS detects a minority-carrier electron trap level with an activation energy of 0.45 eV on the sample that contained defects as seen by imaging.

  2. Growing antiphase-domain-free GaAs thin films out of highly ordered planar nanowire arrays on exact (001) silicon

    SciTech Connect (OSTI)

    Li, Qiang; Ng, Kar Wei; Lau, Kei May

    2015-02-16

    We report the use of highly ordered, dense, and regular arrays of in-plane GaAs nanowires as building blocks to produce antiphase-domain-free GaAs thin films on exact (001) silicon. High quality GaAs nanowires were grown on V-grooved Si (001) substrates using the selective aspect ratio trapping concept. The 4.1% lattice mismatch has been accommodated by the initial GaAs, a few nanometer-thick with high density stacking faults. The bulk of the GaAs wires exhibited smooth facets and a low defect density. An unusual defect trapping mechanism by a tiara-like structure formed by Si undercuts was discovered. As a result, we were able to grow large-area antiphase-domain-free GaAs thin films out of the nanowires without using SiO{sub 2} sidewalls for defect termination. Analysis from XRD ?-rocking curves yielded full-width-at-half-maximum values of 238 and 154?arc sec from 900 to 2000?nm GaAs thin films, respectively, indicating high crystalline quality. The growth scheme in this work offers a promising path towards integrated III-V electronic, photonic, or photovoltaic devices on large scale silicon platform.

  3. EERE Success Story-California: TetraCell Silicon Solar Cell Improves...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    This innovative PV technology reduces costs with a simplified process that replaces silver-a high-cost commodity used in traditional screen printed solar cells-with copper, which ...

  4. Silicon Border Development LLC | Open Energy Information

    Open Energy Info (EERE)

    Silicon Border Development LLC Jump to: navigation, search Name: Silicon Border Development LLC Place: Poway, California Zip: 92064 Sector: Solar Product: US-based developer of...

  5. Efficient Crystalline Si Solar Cell with Amorphous/Crystalline Silicon Heterojunction as Back Contact: Preprint

    SciTech Connect (OSTI)

    Nemeth, B.; Wang, Q.; Shan, W.

    2012-06-01

    We study an amorphous/crystalline silicon heterojunction (Si HJ) as a back contact in industrial standard p-type five-inch pseudo-square wafer to replace Al back surface field (BSF) contact. The best efficiency in this study is over 17% with open-circuit (Voc) of 0.623 V, which is very similar to the control cell with Al BSF. We found that Voc has not been improved with the heterojunction structure in the back. The typical minority carrier lifetime of these wafers is on the order of 10 us. We also found that the doping levels of p-layer affect the FF due to conductivity and band gap shifting, and an optimized layer is identified. We conclude that an amorphous/crystalline silicon heterojunction can be a very promising structure to replace Al BSF back contact.

  6. 11th Workshop on Crystalline Silicon Solar Cell Materials and Processes, Extended Abstracts and Papers, 19-22 August 2001, Estes Park, Colorado

    SciTech Connect (OSTI)

    Sopori, B.

    2001-08-16

    The 11th Workshop will provide a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and non-photovoltaic fields. Discussions will include the various aspects of impurities and defects in silicon--their properties, the dynamics during device processing, and their application for developing low-cost processes for manufacturing high-efficiency silicon solar cells. Sessions and panel discussions will review impurities and defects in crystalline-silicon PV, advanced cell structures, new processes and process characterization techniques, and future manufacturing demands. The workshop will emphasize some of the promising new technologies in Si solar cell fabrication that can lower PV energy costs and meet the throughput demands of the future. The three-day workshop will consist of presentations by invited speakers, followed by discussion sessions. Topics to be discussed are: Si Mechanical properties and Wafer Handling, Advanced Topics in PV Fundamentals, Gettering and Passivation, Impurities and Defects, Advanced Emitters, Crystalline Silicon Growth, and Solar Cell Processing. The workshop will also include presentations by NREL subcontractors who will review the highlights of their research during the current subcontract period. In addition, there will be two poster sessions presenting the latest research and development results. Some presentations will address recent technologies in the microelectronics field that may have a direct bearing on PV.

  7. Excellent Passivation and Low Reflectivity Al2O3/TiO2 Bilayer Coatings for n-Wafer Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Lee, B. G.; Skarp, J.; Malinen, V.; Li, S.; Choi, S.; Branz, H. M.

    2012-06-01

    A bilayer coating of Al2O3 and TiO2 is used to simultaneously achieve excellent passivation and low reflectivity on p-type silicon. This coating is targeted for achieving high efficiency n-wafer Si solar cells, where both passivation and anti-reflection (AR) are needed at the front-side p-type emitter. It could also be valuable for front-side passivation and AR of rear-emitter and interdigitated back contact p-wafer cells. We achieve high minority carrier lifetimes {approx}1 ms, as well as a nearly 2% decrease in absolute reflectivity, as compared to a standard silicon nitride AR coating.

  8. Fabrication of contacts for silicon solar cells including printing burn through layers

    DOE Patents [OSTI]

    Ginley, David S; Kaydanova, Tatiana; Miedaner, Alexander; Curtis, Calvin J; Van Hest, Marinus Franciscus Antonius Maria

    2014-06-24

    A method for fabricating a contact (240) for a solar cell (200). The method includes providing a solar cell substrate (210) with a surface that is covered or includes an antireflective coating (220). For example, the substrate (210) may be positioned adjacent or proximate to an outlet of an inkjet printer (712) or other deposition device. The method continues with forming a burn through layer (230) on the coating (220) by depositing a metal oxide precursor (e.g., using an inkjet or other non-contact printing method to print or apply a volume of liquid or solution containing the precursor). The method includes forming a contact layer (240) comprising silver over or on the burn through layer (230), and then annealing is performed to electrically connect the contact layer (240) to the surface of the solar cell substrate (210) through a portion of the burn through layer (230) and the coating (220).

  9. Processing and modeling issues for thin-film solar cell devices: Annual subcontract report, January 16, 1995 -- January 15, 1996

    SciTech Connect (OSTI)

    Birkmire, R.W.; Phillips, J.E.; Buchanan, W.A.; Eser, E.; Hegedus, S.S.; McCandless, B.E.; Meyers, P.V.; Shafarman, W.N.

    1996-08-01

    The overall mission of the Institute of Energy Conversion is the development of thin film photovoltaic cells, modules, and related manufacturing technology and the education of students and professionals in photovoltaic technology. The objectives of this four-year NREL subcontract are to advance the state of the art and the acceptance of thin film PV modules in the areas of improved technology for thin film deposition, device fabrication, and material and device characterization and modeling, relating to solar cells based on CuInSe{sub 2} and its alloys, on a-Si and its alloys, and on CdTe. In the area of CuInSe{sub 2} and its alloys, EEC researchers have produced CuIn{sub 1-x}GaxSe{sub 2} films by selenization of elemental and alloyed films with H{sub 2}Se and Se vapor and by a wide variety of process variations employing co-evaporation of the elements. Careful design, execution and analysis of these experiments has led to an improved understanding of the reaction chemistry involved, including estimations of the reaction rate constants. Investigation of device fabrication has also included studies of the processing of the Mo, US and ZnO deposition parameters and their influence on device properties. An indication of the success of these procedures was the fabrication of a 15% efficiency CuIn{sub 1-x}GaxSe{sub 2} solar cell.

  10. High-efficiency, thin-film solar cells. Annual subcontractor report, 1 July 1991--30 June 1992

    SciTech Connect (OSTI)

    Gale, R.P.

    1994-01-01

    This report describes work on a 3-year research program to investigate thin-film GaAs/GaInP cells using the cleavage of lateral epitaxial film for transfer (CLEFT) technique, and to determine the process to enable overgrowth of GaAs films using organometallic chemistry. Application of the CLEFT thin-film technique to GaInP/GaAs solar cells and organometallic overgrowth was investigated. A problem of alloy contamination was identified and controlled, leading to higher quality layers. Solar cell structures were grown and fabricated using previously determined growth parameters for GaAs and GaInP. With the improved materials developed significant improvements were made in solar cell performance. Conditions for in-situ overgrowth by organometallic chemical vapor deposition (OMCVD) were determined and continuous GaAs layers were grown over a separation mask layer. The layers were successfully separated from their substrate using the CLEFT process, demonstrating the application of overgrowth using OM chemistry with HCl.

  11. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1996-01-30

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  12. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1998-06-02

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  13. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1998-06-02

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  14. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1996-01-01

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  15. Manipulating hybrid structures of polymer/a-Si for thin film solar cells

    SciTech Connect (OSTI)

    Peng, Ying; He, Zhiqun, E-mail: zhqhe@bjtu.edu.cn, E-mail: J.I.B.Wilson@hw.ac.uk; Zhang, Zhi; Liang, Chunjun [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China); Diyaf, Adel; Ivaturi, Aruna; Wilson, John I. B., E-mail: zhqhe@bjtu.edu.cn, E-mail: J.I.B.Wilson@hw.ac.uk [SUPA, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

    2014-03-10

    A series of uniform polymer/amorphous silicon hybrid structures have been fabricated by means of solution-casting for polymer and radio frequency excited plasma enhanced chemical vapour deposition for amorphous silicon (a-Si:H). Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) functioned as a photoactive donor, while the silicon layer acted as an acceptor. It is found that matching the hole mobility of the polymer to the electron mobility of amorphous silicon is critical to improve the photovoltaic performance from hybrid cells. A three-layer p-i-n structure of ITO/PEDOT:PSS(200?nm)/i-Si(450?nm)/n-Si(200?nm)/Al with a power conversion efficiency of 4.78% under a standard test condition was achieved.

  16. Passivated Tunneling Contacts to N-Type Wafer Silicon and Their Implementation into High Performance Solar Cells: Preprint

    SciTech Connect (OSTI)

    Stradins, P.; Essig, S.; Nemeth, W.; Lee, B. G.; Young, D.; Norman, A.; Liu, Y.; Luo, J.-W.; Warren, E.; Dameron, A.; LaSalvia, V.; Page, M.; Rohatgi, A.; Upadhyaya, A.; Rounsaville, B.; Ok, Y.-W.; Glunz, S.; Benick, J.; Feldmann, F.; Hermle, M.

    2014-12-01

    We present a case that passivated contacts based on a thin tunneling oxide layer, combined with a transport layer with properly selected work function and band offsets, can lead to high efficiency c-Si solar cells. Passivated contacts contribute to cell efficiency as well as design flexibility, process robustness, and a simplified process flow. Material choices for the transport layer are examined, including transparent n-type oxides and n+-doped poly-Si. SiO2/n+-poly-Si full-area, induced-junction back surface field contacts to n-FZ and n-Cz Si are incorporated into high efficiency cells with deep, passivated boron emitters.

  17. Novel R2R Manufacturable Photonic-Enhanced Thin Film Solar Cells; January 28, 2010 -- January 31, 2011

    SciTech Connect (OSTI)

    Slafer, D.; Dalal, V.

    2012-03-01

    Final subcontract report for PV Incubator project 'Novel R2R Manufacturable Photonic-Enhanced Thin Film Solar Cells.' The goal of this program was to produce tandem Si cells using photonic bandgap enhancement technology developed at ISU and Lightwave Power that would have an NREL-verified efficiency of 7.5% on 0.25 cm{sup 2} area tandem junction cell on plastic substrates. This goal was met and exceeded within the timeframe and budget of the program. On smaller area cells, the efficiency was even higher, {approx}9.5% (not verified by NREL). Appropriate polymers were developed to fabricate photonic and plasmonic devices on stainless steel, Kapton and PEN substrates. A novel photonic-plasmon structure was developed which shows a promise of improving light absorption in thin film cells, a better light absorption than by any other scheme.

  18. Ultra-thin GaAs single-junction solar cells integrated with a reflective back scattering layer

    SciTech Connect (OSTI)

    Yang, Weiquan; Becker, Jacob; Liu, Shi; Kuo, Ying-Shen; Li, Jing-Jing; Zhang, Yong-Hang; Landini, Barbara; Campman, Ken

    2014-05-28

    This paper reports the proposal, design, and demonstration of ultra-thin GaAs single-junction solar cells integrated with a reflective back scattering layer to optimize light management and minimize non-radiative recombination. According to our recently developed semi-analytical model, this design offers one of the highest potential achievable efficiencies for GaAs solar cells possessing typical non-radiative recombination rates found among commercially available III-V arsenide and phosphide materials. The structure of the demonstrated solar cells consists of an In{sub 0.49}Ga{sub 0.51}P/GaAs/In{sub 0.49}Ga{sub 0.51}P double-heterostructure PN junction with an ultra-thin 300?nm thick GaAs absorber, combined with a 5??m thick Al{sub 0.52}In{sub 0.48}P layer with a textured as-grown surface coated with Au used as a reflective back scattering layer. The final devices were fabricated using a substrate-removal and flip-chip bonding process. Solar cells with a top metal contact coverage of 9.7%, and a MgF{sub 2}/ZnS anti-reflective coating demonstrated open-circuit voltages (V{sub oc}) up to 1.00?V, short-circuit current densities (J{sub sc}) up to 24.5?mA/cm{sup 2}, and power conversion efficiencies up to 19.1%; demonstrating the feasibility of this design approach. If a commonly used 2% metal grid coverage is assumed, the anticipated J{sub sc} and conversion efficiency of these devices are expected to reach 26.6?mA/cm{sup 2} and 20.7%, respectively.

  19. Recent progress on the self-aligned, selective-emitter silicon solar cell

    SciTech Connect (OSTI)

    Ruby, D.S.; Yang, P.; Roy, M.

    1997-10-01

    We developed a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial, screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. We succeeded in finding a set of parameters which resulted in good emitter uniformity and improved cell performance. We used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed, multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. Our initial results found a statistically significant improvement of half an absolute percentage point in cell efficiency when the self-aligned emitter etchback was combined with a 3-step PECVD-nitride surface passivation and hydrogenation treatment. 12 refs., 4 figs., 3 tabs.

  20. Low-Cost Light Weigh Thin Film Solar Concentrators | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    513_ganapathi.pdf More Documents & Publications 2014 SunShot Initiative Portfolio Book: Concentrating Solar Power 2014 SunShot Initiative Peer Review Report

  1. High-Efficiency Amorphous Silicon and Nanocrystalline Silicon Based Solar Cells and Modules: Annual Technical Progress Report, 30 January 2006 - 29 January 29, 2007

    SciTech Connect (OSTI)

    Guha, S.; Yang, J.

    2007-07-01

    United Solar used a-Si:H/a-SiGe:H/a-SiGe:H in two manufacturing plants and improved solar efficiency and reduced manufacturing cost by new deposition methods, optimized deposition parameters, and new materials and cell structures.

  2. Fuyuan Silicon Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Fuyuan Silicon Co Ltd Place: Baishan, Jilin Province, China Sector: Solar Product: A Chinese solar-grade polysilicon producer using metallurgical method. Coordinates:...

  3. Advances in amorphous silicon photovoltaic technology

    SciTech Connect (OSTI)

    Carlson, D.E.; Rajan, K.; Arya, R.R.; Willing, F.; Yang, L.

    1998-10-01

    With the advent of new multijunction thin film solar cells, amorphous silicon photovoltaic technology is undergoing a commercial revival with about 30 megawatts of annual capacity coming on-line in the next year. These new {ital a}{endash}Si multijunction modules should exhibit stabilized conversion efficiencies on the order of 8{percent}, and efficiencies over 10{percent} may be obtained in the next several years. The improved performance results from the development of amorphous and microcrystalline silicon alloy films with improved optoelectronic properties and from the development of more efficient device structures. Moreover, the manufacturing costs for these multijunction modules using the new large-scale plants should be on the order of {dollar_sign}1 per peak watt. These new modules may find widespread use in solar farms, photovoltaic roofing, as well as in traditional remote applications. {copyright} {ital 1998 Materials Research Society.}

  4. Development of low cost contacts to silicon solar cells. Final report, 15 October 1978-30 April 1980

    SciTech Connect (OSTI)

    Tanner, D.P.; Iles, P.A.

    1980-01-01

    A summary of work done on the development of a copper based contact system for silicon solar cells is presented. The work has proceeded in three phases: (1) Development of a copper based contact system using plated Pd-Cr-Cu. Good cells were made but cells degraded under low temperature (300/sup 0/C) heat treatments. (2) The degradation in Phase I was identified as copper migration into the cells junction region. A paper study was conducted to find a proper barrier to the copper migration problem. Nickel was identified as the best candidate barrier and this was verified in a heat treatment study using evaporated metal layers. (3) An electroless nickel solution was substituted for the electroless chrominum solution in the original process. Efforts were made to replace the palladium bath with an appropriate nickel layer, but these were unsuccessful. 150 cells using the Pd-Ni-Cu contact system were delivered to JPL. Also a cost study was made on the plating process to assess the chance of reaching 5 cents/watt.

  5. Bioinspired Molecular Co-Catalysts Bonded to a Silicon Photocathode for Solar Hydrogen Evolution

    SciTech Connect (OSTI)

    Hou, Yidong

    2011-11-08

    The production of fuels from sunlight represents one of the main challenges in the development of a sustainable energy system. Hydrogen is the simplest fuel to produce and although platinum and other noble metals are efficient catalysts for photoelectrochemical hydrogen evolution earth-abundant alternatives are needed for large-scale use. We show that bioinspired molecular clusters based on molybdenum and sulphur evolve hydrogen at rates comparable to that of platinum. The incomplete cubane-like clusters (Mo{sub 3}S{sub 4}) efficiently catalyse the evolution of hydrogen when coupled to a p-type Si semiconductor that harvests red photons in the solar spectrum. The current densities at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10% (ref. 16). The experimental observations are supported by density functional theory calculations of the Mo{sub 3}S{sub 4} clusters adsorbed on the hydrogen-terminated Si(100) surface, providing insights into the nature of the active site.

  6. Array automated assembly task low cost silicon solar array project. Phase 2. Final report

    SciTech Connect (OSTI)

    Olson, Clayton

    1980-12-01

    The initial contract was a Phase II Process Development for a process sequence, but with concentration on two particular process steps: laserscribing and spray-on junction formation. The add-on portion of the contract was to further develop these tasks, to incorporate spray-on of AR Coating and aluminum and to study the application of microwave energy to solar cell fabrication. The overall process cost projection is 97.918 cents/Wp. The major contributor to this excess cost is the module encapsulation materials cost. During the span of this contract the study of microwave application to solar cell fabrication produced the ability to apply this technique to any requirement of 600/sup 0/C or less. Above this temperature, non-uniformity caused the processing to be unreliable. The process sequence is described in detail, and a SAMICS cost analysis for each valid process step studied is presented. A temporary catalog for expense items is included, and engineering specifications for the process steps are given. (WHK)

  7. Structural and Optical Investigations of GaN-Si Interface for a Heterojunction Solar Cell

    SciTech Connect (OSTI)

    Williams, Joshua J.; Jeffries, April M.; Bertoni, Mariana I.; Williamson, Todd L.; Bowden, Stuart G.; Honsberg, Christiana B.

    2014-06-08

    In recent years the development of heterojunction silicon based solar cells has gained much attention, lea largely by the efforts of Panasonic’s HIT cell. The success of the HIT cell prompts the scientific exploration of other thin film layers, besides the industrially accepted amorphous silicon. In this paper we report upon the use of gallium nitride, grown by MBE at “low temperatures” (~200°C), on silicon wafers as one possible candidate for making a heterojunction solar cell; the first approximation of band alignments between GaN and Si; and the material quality as determined by X-ray diffraction.

  8. TiO2 Nanotubes with a ZnO Thin Energy Barrier for Improved Current Efficiency of CdSe Quantum-Dot-Sensitized Solar Cells

    SciTech Connect (OSTI)

    Lee, W.; Kang, S. H.; Kim, J. Y.; Kolekar, G. B.; Sung, Y. E.; Han, S. H.

    2009-01-01

    This paper reports the formation of a thin ZnO energy barrier between a CdSe quantum dot (Q dots) sensitizer and TiO{sub 2} nanotubes (TONTs) for improved current efficiency of Q dot-sensitized solar cells. The formation of a ZnO barrier between TONTs and the Q dot sensitizer increased the short-circuit current under illumination and also reduced the dark current in a dark environment. The power conversion efficiency of Q dot-sensitized TONT solar cells increased by 25.9% in the presence of the ZnO thin layer due to improved charge-collecting efficiency and reduced recombination.

  9. Low-cost thin-material solar technology, the key to a viable energy alternative

    SciTech Connect (OSTI)

    Wilhelm, W.G.; Ripel, B.D.

    1985-08-01

    The creation of a solar technology based on a dramatic reduction in material intensity and greater simplicity of design is the result of a cost-guided research approach. It takes advantage of a progressive material science based on polymer films and unique construction methods that optimize material requirements, performance and durability. The current level of technical maturity has revealed a solar collector design that has the potential for a dramatic reduction in installed cost while maintaining high thermal performance and durability. In addition, the same methodology has guided total solar system designs with similar economies and performance advantages.

  10. Light-trapped interconnected, Silicon-Film{trademark} modules. Annual technical status report, 18 November 1995--18 November 1996

    SciTech Connect (OSTI)

    Hall, R.B.; Rand, J.A.; Cotter, J.E.; Ford, D.H.

    1997-02-01

    AstroPower is developing a module-manufacturing technology based on a film-silicon technology. AstroPower, as a Technology Partner in the Thin-Film PV Partnership, is employing its Silicon-Film{trademark} technology to develop an advanced thin-silicon-based product. This module will combine the design and process features of the most advanced thin-silicon solar cells with light-trapping. These cells will be integrated into a low-cost interconnected array. During the second year of the 3-year project, AstroPower`s emphasis was on developing key submodule fabrication processes. Key results of the work include developing a new thin-film growth concept process based on attaching the low-cost substrate to the thin silicon layer after film growth; developing a new technique to achieve light-trapping in thin layers of silicon based on pigmented high-temperature glass materials; and developing key submodule fabrication processes, including contact grid design, subelement isolation, and screen-printed interconnection.

  11. Wacker Schott Solar GmbH | Open Energy Information

    Open Energy Info (EERE)

    Solar GmbH Place: Alzenau, Germany Sector: Solar Product: JV set up between Wacker Chemie and Schott Solar to produce multicrystalline silicon ingots and solar wafers....

  12. Barrier Coatings for Thin Film Solar Cells: Final Subcontract Report, September 1, 2002 -- January 30, 2008

    SciTech Connect (OSTI)

    Olsen, L. C.

    2010-03-01

    This program has involved investigations of the stability of CdTe and copper-indium-gallium-diselenide (CIGS) solar cells under damp heat conditions and effects of barrier coatings.

  13. CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and...

    Office of Scientific and Technical Information (OSTI)

    the latter were used for the bulk of the process development work, and a 14.4%-efficient solar cell was fabricated. The deposition method is new and offers some advantages over...

  14. Low-cost solar collectors using thin-film plastics absorbers and glazings

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1980-01-01

    The design, fabrication, performance, cost, and marketing of flat plate solar collectors using plastic absorbers and glazings are described. Manufacturing cost breakdowns are given for single-glazed and double-glazed collectors. (WHK)

  15. Light trapping in thin film solar cells using textured photonic crystal

    DOE Patents [OSTI]

    Yi, Yasha (Somerville, MA); Kimerling, Lionel C. (Concord, MA); Duan, Xiaoman (Amesbury, MA); Zeng, Lirong (Cambridge, MA)

    2009-01-27

    A solar cell includes a photoactive region that receives light. A photonic crystal is coupled to the photoactive region, wherein the photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light.

  16. Three-junction solar cells comprised of a thin-film GaInP/GaAs tandem cell mechanically stacked on a Si cell

    SciTech Connect (OSTI)

    Yazawa, Y.; Tamura, K.; Watahiki, S.; Kitatani, T.; Ohtsuka, H.; Warabisako, T.

    1997-12-31

    Three-junction tandem solar cells were fabricated by mechanical stacking of a thin-film GaInP/GaAs monolithic tandem cell and a Si cell. The epitaxial lift-off (ELO) technique was used for the thinning of GaInP/GaAs tandem cells. Both spectral responses of the GaInP top cell and the GaAs middle cell in the thin-film GaInP/GaAs monolithic tandem cell were conserved. The Si cell performance has been improved by reducing the absorption loss in the GaAs substrate.

  17. Graphene-silicon layered structures on single-crystalline Ir...

    Office of Scientific and Technical Information (OSTI)

    Accepted Manuscript: Graphene-silicon layered structures on single-crystalline Ir(111) thin films Prev Next Title: Graphene-silicon layered structures on single-crystalline...

  18. Damp-Heat Induced Degradation of Transparent Conducting Oxides for Thin Film Solar Cells (Presentation)

    SciTech Connect (OSTI)

    Pern, J.; Noufi, R.; Li, X.; DeHart, C.; To, B.

    2008-05-01

    The objectives are: (1) To achieve a high long-term performance reliability for the thin-film CIGS PV modules with more stable materials, device structure designs, and moisture-resistant encapsulation materials and schemes; (2) to evaluate the DH stability of various transparent conducting oxides (TCOs); (3) to identify the degradation mechanisms and quantify degradation rates; (4) to seek chemical and/or physical mitigation methods, and explore new materials. It's important to note that direct exposure to DH represents an extreme condition that a well-encapsulated thin film PV module may never experience.

  19. Low-cost light-weight thin material solar heating system

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1985-03-01

    Presented in this paper are innovative concepts to substantially reduce the cost of residential solar application. They were based on a research and development approach that establishes cost goals which if successfully met can insure high marketability. Included in this cost goal-oriented approach is the additional need to address aesthetics and performance. With such constraints established, designs were initialized, tested, and iterated towards appropriate solutions. These solutions are based on methods for reducing the material intensity of the products, improving the simplicity for ease of production, and reducing the cost of installation. Such a development approach has yielded past proof-of-concept designs in the solar collector and in the other components that constitute a total solar heating system.

  20. Air stable n-doping of WSe{sub 2} by silicon nitride thin films with tunable fixed charge density

    SciTech Connect (OSTI)

    Chen, Kevin; Kiriya, Daisuke; Hettick, Mark; Tosun, Mahmut; Ha, Tae-Jun; Madhvapathy, Surabhi Rao; Desai, Sujay; Sachid, Angada; Javey, Ali

    2014-09-01

    Stable n-doping of WSe{sub 2} using thin films of SiN{sub x} deposited on the surface via plasma-enhanced chemical vapor deposition is presented. Positive fixed charge centers inside SiN{sub x} act to dope WSe{sub 2} thin flakes n-type via field-induced effect. The electron concentration in WSe{sub 2} can be well controlled up to the degenerate limit by simply adjusting the stoichiometry of the SiN{sub x} through deposition process parameters. For the high doping limit, the Schottky barrier width at the metal/WSe{sub 2} junction is significantly thinned, allowing for efficient electron injection via tunneling. Using this doping scheme, we demonstrate air-stable WSe{sub 2} n-MOSFETs with a mobility of ?70 cm{sup 2}/V?s.

  1. New Pathway Developed to Silicon Quantum Dot Devices (Fact Sheet), Highlights in Science, NREL (National Renewable Energy Laboratory)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Researchers create a way to prepare doped nanocrystal solutions for solar thin films that are nontoxic and less expensive than heavy metal-based thin films. Scientists at the National Renewable Energy Laboratory (NREL) and the University of Minnesota have developed a method for preparing doped colloids (solutions) of silicon nanocrystals (NCs) as potential nontoxic infrared-absorbing and -emitting alternatives to metal chalcogenide quantum dots. Significant progress in the methods for preparing

  2. Silicon-film {trademark} photovoltaic manufacturing technology. Annual subcontract report, 1 January 1994--31 December 1994

    SciTech Connect (OSTI)

    Collins, S.R.; Hall, R.B.; Rand, J.A.

    1995-11-01

    The goal of AstroPower`s PVMaT-2A project is to develop an advanced, low-cost manufacturing process for a new utility-scale, flat-plate module. This process starts with the production of continuous sheets of thin-film polycrystalline silicon using the Silicon-Film {trademark} process. Our main product focus in PVMaT-2A has been a 240 cm{sup 2} solar cell. Continuous sheets of silicon are produced and cut into wafers that are 15.5 cm on a side. Both standard modules (36 solar cells) and a new 56 solar cell module were produced. The targeted high power module design is a 170 watt module, used in a twelve module array to generate 2 kW. The solar cells, modules, and array developed here are described.

  3. .beta.-silicon carbide protective coating and method for fabricating same

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA)

    1994-01-01

    A polycrystalline beta-silicon carbide film or coating and method for forming same on components, such as the top of solar cells, to act as an extremely hard protective surface, and as an anti-reflective coating. This is achieved by DC magnetron co-sputtering of amorphous silicon and carbon to form a SiC thin film onto a surface, such as a solar cell. The thin film is then irradiated by a pulsed energy source, such as an excimer laser, to synthesize the poly- or .mu.c-SiC film on the surface and produce .beta.--SiC. While the method of this invention has primary application in solar cell manufacturing, it has application wherever there is a requirement for an extremely hard surface.

  4. [beta]-silicon carbide protective coating and method for fabricating same

    DOE Patents [OSTI]

    Carey, P.G.; Thompson, J.B.

    1994-11-01

    A polycrystalline beta-silicon carbide film or coating and method for forming same on components, such as the top of solar cells, to act as an extremely hard protective surface, and as an anti-reflective coating are disclosed. This is achieved by DC magnetron co-sputtering of amorphous silicon and carbon to form a SiC thin film onto a surface, such as a solar cell. The thin film is then irradiated by a pulsed energy source, such as an excimer laser, to synthesize the poly- or [mu]c-SiC film on the surface and produce [beta]-SiC. While the method of this invention has primary application in solar cell manufacturing, it has application wherever there is a requirement for an extremely hard surface. 3 figs.

  5. Thin film solar cells by selenization sulfurization using diethyl selenium as a selenium precursor

    DOE Patents [OSTI]

    Dhere, Neelkanth G.; Kadam, Ankur A.

    2009-12-15

    A method of forming a CIGSS absorber layer includes the steps of providing a metal precursor, and selenizing the metal precursor using diethyl selenium to form a selenized metal precursor layer (CIGSS absorber layer). A high efficiency solar cell includes a CIGSS absorber layer formed by a process including selenizing a metal precursor using diethyl selenium to form the CIGSS absorber layer.

  6. SunShot Initiative Workshop on Silicon Photovoltaics | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    SunShot Initiative held a workshop on silicon photovoltaics research directions beyond 2020 in conjunction with the NREL workshop on crystalline silicon solar cells and modules. ...

  7. Schmid Silicon Technology GmbH SST | Open Energy Information

    Open Energy Info (EERE)

    Schmid Silicon Technology GmbH SST Jump to: navigation, search Name: Schmid Silicon Technology GmbH (SST) Place: Freudenstadt, Germany Zip: D-72250 Sector: Solar Product:...

  8. Shaanxi Tianhong Silicon Material Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Tianhong Silicon Material Co Ltd Jump to: navigation, search Name: Shaanxi Tianhong Silicon Material Co Ltd Place: Shaanxi Province, China Sector: Solar Product: A Chinese...

  9. Dawu Silicon Park Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Dawu Silicon Park Co Ltd Jump to: navigation, search Name: Dawu Silicon Park Co Ltd Place: Dawu County, Hubei Province, China Zip: 432800 Sector: Solar Product: Chinese polysilicon...

  10. Atmospheric Pressure Chemical Vapor Deposition of High Silica SiO2-TiO2 Antireflective Thin Films for Glass Based Solar Panels

    SciTech Connect (OSTI)

    Klobukowski, Erik R; Tenhaeff, Wyatt E; McCamy, James; Harris, Caroline; Narula, Chaitanya Kumar

    2013-01-01

    The atmospheric pressure chemical vapor deposition (APCVD) of SiO2-TiO2 thin films employing [[(tBuO)3Si]2O-Ti(OiPr)2], which can be prepared from commercially available materials, results in antireflective thin films on float glass under industrially relevant manufacturing conditions. It was found that while the deposition temperature had an effect on the SiO2:TiO2 ratio, the thickness was dependent on the time of deposition. This study shows that it is possible to use APCVD employing a single source precursor containing titanium and silicon to produce thin films on float glass with high SiO2:TiO2 ratios.

  11. Crystalline Silicon Photovoltaics Research | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Crystalline Silicon Photovoltaics Research Crystalline Silicon Photovoltaics Research DOE supports crystalline silicon photovoltaic (PV) research and development efforts that lead to market-ready technologies. Below are a list of the projects, summary of the benefits, and discussion on the production and manufacturing of this solar technology. Background Crystalline silicon PV cells are the most common solar cells used in commercially available solar panels, representing 87% of world PV cell

  12. (Sr,Ba)(Si,Ge){sub 2} for thin-film solar-cell applications: First-principles study

    SciTech Connect (OSTI)

    Kumar, Mukesh E-mail: mkgarg79@gmail.com; Umezawa, Naoto; Imai, Motoharu

    2014-05-28

    In order to meet the increasing demand for electric power generation from solar energy conversion, the development of efficient light absorber materials has been awaited. To this end, the electronic and optical properties of advanced alkaline-earth-metals disilicides and digermanides (SrSi{sub 2}, BaSi{sub 2}, SrGe{sub 2}, and BaGe{sub 2}) are studied by means of the density functional theory using HSE06 exchange-correlation energy functional. Our calculations show that all these orthorhombic structured compounds have fundamental indirect band gaps in the range E{sub g} ? 0.891.25 eV, which is suitable for solar cell applications. The estimated lattice parameters and band gaps are in good agreement with experiments. Our calculations show that the electronic band structures of all four compounds are very similar except in the vicinity of the ?-point. The valence band of these compounds is made up by Si(Ge)-p states, whereas the conduction band is composed of Sr(Ba)-d states. Their band alignments are carefully determined by estimating the work function of each compound using slab model. The optical properties are discussed in terms of the complex dielectric function ?(?)?=??{sub 1}(?)?+?i?{sub 2}(?). The static and high-frequency dielectric constants are calculated, taking into account the ionic contribution. The absorption coefficient ?(?) demonstrates that a low energy dispersion of the conduction band, which results in a flat conduction band minimum, leads to large optical activity in these compounds. Therefore, alkaline-earth-metals disilicides and digermanides possess great potential as light absorbers for applications in thin-film solar cell technologies.

  13. Voltec Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Voltec-Solar Place: Dinsheim Sur Bruche, France Zip: 67190 Product: French manufacturer of crystalline silicon modules. References:...

  14. Auxin Solar | Open Energy Information

    Open Energy Info (EERE)

    Auxin Solar Jump to: navigation, search Name: Auxin Solar Place: Campbell, California Product: Silicon Valley-based Auxin manufactures crystalline PV modules ranging from 10W to...

  15. Phono Solar | Open Energy Information

    Open Energy Info (EERE)

    Phono Solar Jump to: navigation, search Name: Phono Solar Place: Nanjing, China Product: Chinese manufacturer of mono and poly crystalline silicon modules, member of the Jiangsu...

  16. Evolution Solar | Open Energy Information

    Open Energy Info (EERE)

    Product: British Virgin Islands-based solar energy company dedicated to establishing solar panel factories in the Middle East and Africa using both Crystalline Silicon and...

  17. Scatec Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Jump to: navigation, search Name: Scatec Solar Place: Norway Product: Norwegian PV system integrator with a parent, Norsun, that manufactures monocrystalline silicon ingots...

  18. Elkem Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar Product: Norwegian manufacturer of solar grade silicon that uses metallurgical process. Coordinates: 59.91228, 10.74998 Show Map Loading map... "minzoom":false,"map...

  19. Polycrystalline thin film cadmium telluride solar cells fabricated by electrodeposition. Annual technical report, 20 March 1995--19 March 1996

    SciTech Connect (OSTI)

    Trefny, J.U.; Mao, D.

    1997-04-01

    The objective of this project is to develop improved processes for fabricating CdTe/CdS polycrystalline thin-film solar cells. Researchers used electrodeposition to form CdTe; electrodeposition is a non-vacuum, low-cost technique that is attractive for economic, large-scale production. During the past year, research and development efforts focused on several steps that are most critical to the fabricating high-efficiency CdTe solar cells. These include the optimization of the CdTe electrodeposition process, the effect of pretreatment of CdS substrates, the post-deposition annealing of CdTe, and back-contact formation using Cu-doped ZnTe. Systematic investigations of these processing steps have led to a better understanding and improved performance of the CdTe-based cells. Researchers studied the structural properties of chemical-bath-deposited CdS thin films and their growth mechanisms by investigating CdS samples prepared at different deposition times; investigated the effect of CdCl{sub 2} treatment of CdS films on the photovoltaic performance of CdTe solar cells; studied Cu-doped ZnTe as a promising material for forming stable, low-resistance contacts to the p-type CdTe; and investigated the effect of CdTe and CdS thickness on the photovoltaic performance of the resulting cells. As a result of their systematic investigation and optimization of the processing conditions, researchers improved the efficiency of CdTe/CdS cells using ZnTe back-contact and electrodeposited CdTe. The best CdTe/CdS cell exhibited a V{sub oc} of 0.778 V, a J{sub sc} of 22.4 mA/cm{sup 2}, a FF of 74%, and an efficiency of 12.9% (verified at NREL). In terms of individual parameters, researchers obtained a V{sub oc} over 0.8 V and a FF of 76% on other cells.

  20. High efficiency thin film CdTe and a-Si based solar cells

    SciTech Connect (OSTI)

    Compaan, A. D.; Deng, X.; Bohn, R. G.

    2000-01-04

    This report describes work done by the University of Toledo during the first year of this subcontract. During this time, the CdTe group constructed a second dual magnetron sputter deposition facility; optimized reactive sputtering for ZnTe:N films to achieve 10 ohm-cm resistivity and {approximately}9% efficiency cells with a copper-free ZnTe:N/Ni contact; identified Cu-related photoluminescence features and studied their correlation with cell performance including their dependence on temperature and E-fields; studied band-tail absorption in CdS{sub x}Te{sub 1{minus}x} films at 10 K and 300 K; collaborated with the National CdTe PV Team on (1) studies of high-resistivity tin oxide (HRT) layers from ITN Energy Systems, (2) fabrication of cells on the HRT layers with 0, 300, and 800-nm CdS, and (3) preparation of ZnTe:N-based contacts on First Solar materials for stress testing; and collaborated with Brooklyn College for ellipsometry studies of CdS{sub x}Te{sub 1{minus}x} alloy films, and with the University of Buffalo/Brookhaven NSLS for synchrotron X-ray fluorescence studies of interdiffusion in CdS/CdTe bilayers. The a-Si group established a baseline for fabricating a-Si-based solar cells with single, tandem, and triple-junction structures; fabricated a-Si/a-SiGe/a-SiGe triple-junction solar cells with an initial efficiency of 9.7% during the second quarter, and 10.6% during the fourth quarter (after 1166 hours of light-soaking under 1-sun light intensity at 50 C, the 10.6% solar cells stabilized at about 9%); fabricated wide-bandgap a-Si top cells, the highest Voc achieved for the single-junction top cell was 1.02 V, and top cells with high FF (up to 74%) were fabricated routinely; fabricated high-quality narrow-bandgap a-SiGe solar cells with 8.3% efficiency; found that bandgap-graded buffer layers improve the performance (Voc and FF) of the narrow-bandgap a-SiGe bottom cells; and found that a small amount of oxygen partial pressure ({approximately}2 {times} 10{sup {minus}5} torr) was beneficial for growing high-quality films from ITO targets.

  1. Glass-silicon column

    DOE Patents [OSTI]

    Yu, Conrad M.

    2003-12-30

    A glass-silicon column that can operate in temperature variations between room temperature and about 450.degree. C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  2. DOE Offers Support for Innovative Manufacturing Plant That Will Produce High Quality Solar Silicon at Low Cost

    Broader source: Energy.gov [DOE]

    Project to Create Significant Solar Manufacturing Efficiencies and is Expected to Generate Over 2,000 Jobs

  3. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells. Final subcontract report, 1 July 1988--31 December 1991

    SciTech Connect (OSTI)

    Chu, T.L.

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

  4. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power ... Hydrogen Infrastructure Hydrogen Production Market Transformation Fuel Cells ...

  5. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Conversion Efficiency Solar Energy Wind Energy Water ... Infrastructure Hydrogen Production Market Transformation ... Tribal Energy Program Intellectual Property Current EC ...

  6. 12th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Extended Abstracts and Papers, August 11-14, 2002, Breckenridge, Colorado

    SciTech Connect (OSTI)

    Sopori, B. L.

    2002-08-01

    The 12th Workshop will provide a forum for an informal exchange of technical and scientific information between international researchers in the photovoltaic and relevant non-photovoltaic fields. Discussions will include various aspects of impurities and defects in silicon-their properties, the dynamics during processing, and their application for developing low-cost processes for manufacturing high-efficiency silicon solar cells. The workshop will emphasize some of the promising new technologies in Si solar cell fabrication that can lower PV energy costs and meet the production demands of the future. It will also provide an excellent opportunity for researchers, in private industry and at universities, to prioritize mutual needs for future collaborative research. Sessions and panel discussions will review recent advances in crystal growth, new cell structures, new processes and process characterization techniques, and manufacturing approaches suitable for future manufacturing demands . Some presentations will address recent technologies in the microelectronics field that may have a direct bearing on PV. The three-day workshop will consist of presentations by invited speakers, followed by discussion sessions. In addition, there will be two poster sessions presenting the latest research and development results.

  7. TGI Solar Power Group | Open Energy Information

    Open Energy Info (EERE)

    Solar Product: TGI Solar Power Group specialises in the manufacture and integration of thin film PV fabrication lines, PV thin film manufacturing equipment, as well as project...

  8. Progress in passive solar energy systems. Volume 8. Part 1

    SciTech Connect (OSTI)

    Hayes, J.; Andrejko, D.A.

    1983-01-01

    This book presents the papers given at a conference sponsored by the US DOE, the Solar Energy Research Institute, SolarVision, Inc., and the Southern California Solar Energy Society. The topics considered at the conference included sizing solar energy systems for agricultural applications, a farm scale ethanol production plant, the EEC wind energy RandD program, the passive solar performance assessment of an earth-sheltered house, the ARCO 1 MW photovoltaic power plant, the performance of a dendritic web photovoltaic module, second generation point focused concentrators, linear fresnel lens concentrating photovoltaic collectors, photovoltaic conversion efficiency, amorphous silicon thin film solar cells, a photovoltaic system for a shopping center, photovoltaic power generation for the utility industry, spectral solar radiation, and the analysis of insolation data.

  9. Efficient Nanostructured Silicon (Black Silicon) PV Devices - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Efficient Nanostructured Silicon (Black Silicon) PV Devices National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary Antireflective (AR) coatings on solar cells increase the efficiency of the cells by suppressing reflection, which allows more photons to enter a silicon (Si) wafer and increases the flow of electricity. Traditional AR coatings however, add significant cost to the solar cell manufacturing process. NREL scientists

  10. High-Efficiency Amorphous Silicon and Nanocrystalline Silicon-Based Solar Cells and Modules: Final Technical Progress Report, 30 January 2006 - 29 January 2008

    SciTech Connect (OSTI)

    Guha, S.; Yang, J.

    2008-05-01

    United Solar Ovonic successfully used its spectrum-splitting a-Si:H/a-SiGe:H/a-SiGe:H triple-junction structure in their manufacturing plants, achieving a manufacturing capacity of 118 MW in 2007, and set up a very aggressive expansion plan to achieve grid parity.

  11. Silicon-Film{trademark} photovoltaic manufacturing technology. Semiannual subcontract report, 15 October 1993--15 April 1994

    SciTech Connect (OSTI)

    Collins, S.R.; Hall, R.B.

    1994-09-01

    This report describes work to develop an advanced, low-cost manufacturing process for a now utility-scale, flat-plate module. This process starts with the production of continuous sheets of thin-film, polycrystalline silicon using the Silicon-Film{trademark} process. Sheets are cut into wafers that are nominally 15 cm on a side. Fifty-six of these wafers are then fabricated into solar cells that are strung together into a 170-W module. Twelve of these modules form a 2-kW array. The program has three main components: (1) development of a Silicon-Film{trademark} wafer machine that is capable of manufacturing waters that are 225 cm{sup 2} in size at a rate of 3.0 MW/yr, with a total product cost reduction of 70%; (2) development of an advanced solar cell manufacturing process that is capable of turning the Silicon-Film{trademark} wafer into a 3.25-W solar cell; and (3) development of an advanced module design based on these large-area silicon solar cells with an average power of 170 W for 56 solar cells and 113 W for 36 solar cells.

  12. Process for fabricating polycrystalline semiconductor thin-film solar cells, and cells produced thereby

    DOE Patents [OSTI]

    Wu, Xuanzhi (Golden, CO); Sheldon, Peter (Lakewood, CO)

    2000-01-01

    A novel, simplified method for fabricating a thin-film semiconductor heterojunction photovoltaic device includes initial steps of depositing a layer of cadmium stannate and a layer of zinc stannate on a transparent substrate, both by radio frequency sputtering at ambient temperature, followed by the depositing of dissimilar layers of semiconductors such as cadmium sulfide and cadmium telluride, and heat treatment to convert the cadmium stannate to a substantially single-phase material of a spinel crystal structure. Preferably, the cadmium sulfide layer is also deposited by radio frequency sputtering at ambient temperature, and the cadmium telluride layer is deposited by close space sublimation at an elevated temperature effective to convert the amorphous cadmium stannate to the polycrystalline cadmium stannate with single-phase spinel structure.

  13. Institute of Photo Electronic Thin Film Devices and Technology...

    Open Energy Info (EERE)

    Place: Tianjin Municipality, China Zip: 300071 Sector: Solar Product: A thin-film solar cell research institute in China. References: Institute of Photo-Electronic Thin...

  14. Enhanced optoelectronic quality of perovskite thin films with hypophosphorous acid for planar heterojunction solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Wei; Pathak, Sandeep; Sakai, Nobuya; Stergiopoulos, Thomas; Nayak, Pabitra K.; Noel, Nakita K.; Haghighirad, Amir A.; Burlakov, Victor M.; deQuilettes, Dane W.; Sadhanala, Aditya; et al

    2015-11-30

    Solution-processed metal halide perovskite semiconductors, such as CH3NH3PbI3, have exhibited remarkable performance in solar cells, despite having non-negligible density of defect states. A likely candidate is halide vacancies within the perovskite crystals, or the presence of metallic lead, both generated due to the imbalanced I/Pb stoichiometry which could evolve during crystallization. Herein, we show that the addition of hypophosphorous acid (HPA) in the precursor solution can significantly improve the film quality, both electronically and topologically, and enhance the photoluminescence intensity, which leads to more efficient and reproducible photovoltaic devices. We demonstrate that the HPA can reduce the oxidized I2 backmore » into I-, and our results indicate that this facilitates an improved stoichiometry in the perovskite crystal and a reduced density of metallic lead.« less

  15. Enhanced optoelectronic quality of perovskite thin films with hypophosphorous acid for planar heterojunction solar cells

    SciTech Connect (OSTI)

    Zhang, Wei; Pathak, Sandeep; Sakai, Nobuya; Stergiopoulos, Thomas; Nayak, Pabitra K.; Noel, Nakita K.; Haghighirad, Amir A.; Burlakov, Victor M.; deQuilettes, Dane W.; Sadhanala, Aditya; Li, Wenzhe; Wang, Liduo; Ginger, David S.; Friend, Richard H.; Snaith, Henry J.

    2015-11-30

    Solution-processed metal halide perovskite semiconductors, such as CH3NH3PbI3, have exhibited remarkable performance in solar cells, despite having non-negligible density of defect states. A likely candidate is halide vacancies within the perovskite crystals, or the presence of metallic lead, both generated due to the imbalanced I/Pb stoichiometry which could evolve during crystallization. Herein, we show that the addition of hypophosphorous acid (HPA) in the precursor solution can significantly improve the film quality, both electronically and topologically, and enhance the photoluminescence intensity, which leads to more efficient and reproducible photovoltaic devices. We demonstrate that the HPA can reduce the oxidized I2 back into I-, and our results indicate that this facilitates an improved stoichiometry in the perovskite crystal and a reduced density of metallic lead.

  16. Polycrystalline thin-film cadmium telluride solar cells fabricated by electrodeposition. Annual technical report

    SciTech Connect (OSTI)

    Trefny, J.U.; Mao, D.

    1998-01-01

    During the past year, Colorado School of Mines (CSM) researchers performed systematic studies of the growth and properties of electrodeposition CdS and back-contact formation using Cu-doped ZnTe, with an emphasis on low Cu concentrations. CSM also started to explore the stability of its ZnTe-Cu contacted CdTe solar cells. Researchers investigated the electrodeposition of CdS and its application in fabricating CdTe/CdS solar cells. The experimental conditions they explored in this study were pH from 2.0 to 3.0; temperatures of 80 and 90 C; CdCl{sub 2} concentration of 0.2 M; deposition potential from {minus}550 to {minus}600 mV vs. Ag/AgCl electrode; [Na{sub 2}S{sub 2}O{sub 4}] concentration between 0.005 and 0.05 M. The deposition rate increases with increase of the thiosulfate concentration and decrease of solution pH. Researchers also extended their previous research of ZnTe:Cu films by investigating films doped with low Cu concentrations (< 5 at. %). The low Cu concentration enabled them to increase the ZnTe:Cu post-annealing temperature without causing excessive Cu diffusion into CdTe or formation of secondary phases. The effects of Cu doping concentration and post-deposition annealing temperature on the structural, compositional, and electrical properties of ZnTe were studied systematically using X-ray diffraction, atomic force microscopy, electron microprobe, Hall effect, and conductivity measurements.

  17. Modeling of the electronic transport in multijunction solar cells

    SciTech Connect (OSTI)

    Rau, U.; Goldbach, M.

    1994-12-31

    Simulations of the electrical transport in multijunction thin-film solar cells made from polycrystalline silicon are presented. The authors investigate the effect of the grain size on the efficiency of the multijunction solar cell. Here, they concentrate on micro crystalline material with a high recombination velocity at the grain boundaries of 10{sup 4}cm/s. Typical results of their calculations demonstrate that based on the multijunction design structure consisting of 8 or more layers efficiencies of 14% may be obtained from 12--20 {micro}m thick solar cells.

  18. Wanxiang Silicon Peak Electronics Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    silicon ingots and wafers and subsidiary of the Wanxiang Group which includes solar cell and module maker Wanxiang Solar. Coordinates: 29.140209, 118.405113 Show...

  19. Photochemical Deposition of Semiconductor Thin Films and Their Application for Solar Cells and Gas Sensors

    SciTech Connect (OSTI)

    Ichimura, M.; Gunasekaran, M.; Sueyoshi, T.

    2009-06-01

    The photochemical deposition (PCD) technique was applied for solar cells and gas sensors. CdS and Cd{sub 1-x}Zn{sub x}S were deposited by PCD. Thiosulfate ions S{sub 2}O{sub 3}{sup 2-} act as a reductant and a sulfur source. The SnS absorption layer was deposited by three-step pulse electrochemical deposition. For the CdS/SnS structure, the best cell showed an efficiency of about 0.2%, while for the Cd{sub 1-x}Zn{sub x}S/SnS structure, an efficiency of up to 0.7% was obtained. For the gas sensor application, SnO{sub 2} was deposited by PCD from a solution containing SnSO{sub 4} and HNO{sub 3}. To enhance the sensitivity to hydrogen, Pd was doped by the photochemical doping method. The current increased by a factor of 10{sup 4} upon exposure to 5000 ppm hydrogen within 1 min at room temperature. 10{sup 3} times conductivity increase was observed even for 50 ppm hydrogen.

  20. Material requirements for the adoption of unconventional silicon crystal and wafer growth techniques for high-efficiency solar cells

    SciTech Connect (OSTI)

    Hofstetter, Jasmin; del Caizo, Carlos; Wagner, Hannes; Castellanos, Sergio; Buonassisi, Tonio

    2015-10-15

    Silicon wafers comprise approximately 40% of crystalline silicon module cost and represent an area of great technological innovation potential. Paradoxically, unconventional wafer-growth techniques have thus far failed to displace multicrystalline and Czochralski silicon, despite four decades of innovation. One of the shortcomings of most unconventional materials has been a persistent carrier lifetime deficit in comparison to established wafer technologies, which limits the device efficiency potential. In this perspective article, we review a defect-management framework that has proven successful in enabling millisecond lifetimes in kerfless and cast materials. Control of dislocations and slowly diffusing metal point defects during growth, coupled to effective control of fast-diffusing species during cell processing, is critical to enable high cell efficiencies. As a result, to accelerate the pace of novel wafer development, we discuss approaches to rapidly evaluate the device efficiency potential of unconventional wafers from injection-dependent lifetime measurements.

  1. Material requirements for the adoption of unconventional silicon crystal and wafer growth techniques for high-efficiency solar cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hofstetter, Jasmin; del Cañizo, Carlos; Wagner, Hannes; Castellanos, Sergio; Buonassisi, Tonio

    2015-10-15

    Silicon wafers comprise approximately 40% of crystalline silicon module cost and represent an area of great technological innovation potential. Paradoxically, unconventional wafer-growth techniques have thus far failed to displace multicrystalline and Czochralski silicon, despite four decades of innovation. One of the shortcomings of most unconventional materials has been a persistent carrier lifetime deficit in comparison to established wafer technologies, which limits the device efficiency potential. In this perspective article, we review a defect-management framework that has proven successful in enabling millisecond lifetimes in kerfless and cast materials. Control of dislocations and slowly diffusing metal point defects during growth, coupled tomore » effective control of fast-diffusing species during cell processing, is critical to enable high cell efficiencies. As a result, to accelerate the pace of novel wafer development, we discuss approaches to rapidly evaluate the device efficiency potential of unconventional wafers from injection-dependent lifetime measurements.« less

  2. Solar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas ...

  3. Theoretical Analysis of Effects of Deep Level, Back Contact, and Absorber Thickness on Capacitance-Voltage Profiling of CdTe Thin-Film Solar Cells

    SciTech Connect (OSTI)

    Li, J. V.; Halverson, A. F.; Sulima, O. V.; Bansal, S.; Burst, J. M.; Barnes, T. M.; Gessert, T. A.; Levi, D. H.

    2012-05-01

    The apparent carrier density profile measured by the capacitance-voltage technique in CdTe thin-film solar cells frequently displays a distinctive U-shape. We show that, even assuming a uniform carrier density, such a U-shape may arise from deep levels, a non-ohmic back-contact, and a thin absorber, which are commonly present in practical CdTe thin-film solar cells. A thin CdTe absorber contributes to the right branch of the U-shape due to a punch-through effect at reverse or zero biases, when the CdTe absorber is nearly fully depleted. A rectifying back-contact contributes to both branches of the U-shape due to voltage sharing with the front junction under a forward bias and early punch-through under a reverse bias. Deep levels contribute to the right branch, but also raise the bottom of the U-shape, leading to an overestimate of carrier density.

  4. Silicon micro-mold

    DOE Patents [OSTI]

    Morales, Alfredo M. (Livermore, CA)

    2006-10-24

    The present invention describes a method for rapidly fabricating a robust 3-dimensional silicon-mold for use in preparing complex metal micro-components. The process begins by depositing a conductive metal layer onto one surface of a silicon wafer. A thin photoresist and a standard lithographic mask are then used to transfer a trace image pattern onto the opposite surface of the wafer by exposing and developing the resist. The exposed portion of the silicon substrate is anisotropically etched through the wafer thickness down to conductive metal layer to provide an etched pattern consisting of a series of rectilinear channels and recesses in the silicon which serve as the silicon micro-mold. Microcomponents are prepared with this mold by first filling the mold channels and recesses with a metal deposit, typically by electroplating, and then removing the silicon micro-mold by chemical etching.

  5. Automated solar cell assembly teamed process research. Semiannual subcontract report, 7 January 1993--30 June 1993

    SciTech Connect (OSTI)

    Nowlan, M.J.; Hogan, S.J.; Darkazalli, G.; Breen, W.F.; Murach, J.M.; Sutherland, S.F.

    1994-02-01

    This report describes work done under Phase 3A of the PVMaT project to address problems that are generic to the photovoltaics (PV) industry. Crystalline silicon solar cells were used in the majority of all terrestrial power modules shipped in 1992. Spire`s analysis in Phase 1 of the PVMaT project indicated that the use of thin ({le}200-{mu}m) silicon cells can substantially reduce module manufacturing costs, provided that processing yields remain as high as they are now for processing standard thickness cells. Because present solar cell tabbing and interconnecting processes have unacceptably high yield losses with such thin cells, the objective of this Phase 3A subcontract is to use Spire`s light soldering technology and experience in designing and fabricating solar cell tabbing and interconnecting equipment to develop high yield throughput, fully automated processes for tabbing and interconnecting thin cells.

  6. NREL: Photovoltaics Research - Polycrystalline Thin-Film Materials...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the area of polycrystalline thin-film materials and devices. Printable Version Photovoltaics Research Home Silicon Polycrystalline Thin Films Multijunctions New Materials,...

  7. Shenzhen Topray Solar Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    518108 Sector: Solar Product: Shenzhen Topray Solar Co Ltd produces amorphous silicon solar cells. Coordinates: 22.546789, 114.112556 Show Map Loading map......

  8. Si Passivation and Chemical Vapor Deposition of Silicon Nitride: Final Technical Report, March 18, 2007

    SciTech Connect (OSTI)

    Atwater, H. A.

    2007-11-01

    This report investigated chemical and physical methods for Si surface passivation for application in crystalline Si and thin Si film photovoltaic devices. Overall, our efforts during the project were focused in three areas: i) synthesis of silicon nitride thin films with high hydrogen content by hot-wire chemical vapor deposition; ii) investigation of the role of hydrogen passivation of defects in crystalline Si and Si solar cells by out diffusion from hydrogenated silicon nitride films; iii) investigation of the growth kinetics and passivation of hydrogenated polycrystalline. Silicon nitride films were grown by hot-wire chemical vapor deposition and film properties have been characterized as a function of SiH4/NH3 flow ratio. It was demonstrated that hot-wire chemical vapor deposition leads to growth of SiNx films with controllable stoichiometry and hydrogen.

  9. Synthesis and tribological behavior of silicon oxycarbonitride...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 36 MATERIALS SCIENCE; SILICON COMPOUNDS; SYNTHESIS; THIN FILMS; OXYCARBIDES; NITRIDES; TRIBOLOGY Word Cloud More ...

  10. Becancour Silicon Inc BSI | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search Name: Becancour Silicon Inc (BSI) Place: St. Laurent, Quebec, Canada Zip: H4M2M4 Sector: Solar Product: Canadian supplier of silicon metal for the...

  11. Results of I-V Curves and Visual Inspection of PV Modules Deployed at TEP Solar Test Yard (Poster)

    SciTech Connect (OSTI)

    McNutt, P.; Wohlgemuth, J.; Miller, D.; Stoltenberg, B.

    2014-02-01

    The purpose of the PV Service Life Prediction project is to examine and report on how solar modules are holding up after being in the field for 5 or more years. This poster presents the common problems crystalline-silicon and thin-film modules exhibit, including details of modules from three manufactures that were tested January 13-16, 2014.

  12. Reliability Challenges for Solar Energy (Presentation)

    SciTech Connect (OSTI)

    Kurtz, S.

    2009-12-08

    Presentation that reviews reliability issues related to various types of photovoltaic tecnnologies, including crystalline silicon, thin films, and concentrating PV.

  13. Method For Passivating Crystal Silicon Surfaces - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Method For Passivating Crystal Silicon Surfaces National Renewable Energy Laboratory Contact NREL About This Technology Publications: PDF Document Publication Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements (395 KB) PDF Document Publication High-Throughput Approaches to Optimization of Crystal Silicon Surface Passivation and Heterojunction Solar Cells (837 KB) Technology Marketing

  14. Black Silicon Etching - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search Black Silicon Etching Award-winning, efficient, and inexpensive photovoltaic technology National Renewable Energy Laboratory Contact NREL About This Technology Three silicon wafers, showing absorbed light: (left) micron-scale texture, (center) NREL&rsquo;s Black Silicon Etch, and (right) micron-scale texture with an antireflective coating. Three silicon wafers, showing absorbed light: (left) micron-scale texture,

  15. System and method for liquid silicon containment

    SciTech Connect (OSTI)

    Cliber, James A; Clark, Roger F; Stoddard, Nathan G; Von Dollen, Paul

    2014-06-03

    This invention relates to a system and a method for liquid silicon containment, such as during the casting of high purity silicon used in solar cells or solar modules. The containment apparatus includes a shielding ember adapted to prevent breaching molten silicon from contacting structural elements or cooling elements of a casting device, and a volume adapted to hold a quantity of breaching molten silicon with the volume formed by a bottom and one or more sides.

  16. System and method for liquid silicon containment

    DOE Patents [OSTI]

    Cliber, James A; Clark, Roger F; Stoddard, Nathan G; Von Dollen, Paul

    2013-05-28

    This invention relates to a system and a method for liquid silicon containment, such as during the casting of high purity silicon used in solar cells or solar modules. The containment apparatus includes a shielding member adapted to prevent breaching molten silicon from contacting structural elements or cooling elements of a casting device, and a volume adapted to hold a quantity of breaching molten silicon with the volume formed by a bottom and one or more sides.

  17. Light-trapped, interconnected, silicon-film {trademark} modules. Annual subcontract report, 18 November 1994--18 November 1995

    SciTech Connect (OSTI)

    Hall, R.B.; Rand, J.A.; Cotter, J.E.; Ford, D.H.

    1996-03-01

    This report describes the first year of work performed by AstroPower, Inc., of Newark, Delaware, under the Thin-Film PV Partnership Program. The work led to the development of a new barrier-coated substrate that has enabled high-quality thin-layer polycrystalline silicon to be grown on a low-cost substrate. High diffusion lengths were measured after external phosphorous gettering. This led to a confirmed efficiency for a 0.57cm{sup 2}, thin-layer solar cell grown on a low-cost substrate.

  18. Frequency up-conversion in nonpolar a-plane GaN/AlGaN based multiple quantum wells optimized for applications with silicon solar cells

    SciTech Connect (OSTI)

    Radosavljevi?, S.; Radovanovi?, J. Milanovi?, V.; Tomi?, S.

    2014-07-21

    We have described a method for structural parameters optimization of GaN/AlGaN multiple quantum well based up-converter for silicon solar cells. It involves a systematic tuning of individual step quantum wells by use of the genetic algorithm for global optimization. In quantum well structures, the up-conversion process can be achieved by utilizing nonlinear optical effects based on intersubband transitions. Both single and double step quantum wells have been tested in order to maximize the second order susceptibility derived from the density matrix formalism. The results obtained for single step wells proved slightly better and have been further pursued to obtain a more complex design, optimized for conversion of an entire range of incident photon energies.

  19. Ascent Solar Technologies Inc | Open Energy Information

    Open Energy Info (EERE)

    Sector: Solar Product: Ascent Solar develops and plans to manufacture CIGS thin-film solar cells and modules for the satellite and high-altitude airship (HAA)...

  20. Metal organic chemical vapor deposition of 111-v compounds on silicon

    DOE Patents [OSTI]

    Vernon, Stanley M.

    1986-01-01

    Expitaxial composite comprising thin films of a Group III-V compound semiconductor such as gallium arsenide (GaAs) or gallium aluminum arsenide (GaAlAs) on single crystal silicon substrates are disclosed. Also disclosed is a process for manufacturing, by chemical deposition from the vapor phase, epitaxial composites as above described, and to semiconductor devices based on such epitaxial composites. The composites have particular utility for use in making light sensitive solid state solar cells.

  1. High-Efficiency CdTe and CIGS Thin-Film Solar Cells: Highlights and Challenges; Preprint

    SciTech Connect (OSTI)

    Noufi, R.; Zweibel, K.

    2006-05-01

    Thin-film photovoltaic (PV) modules of CdTe and Cu(In,Ga)Se2 (CIGS) have the potential to reach cost-effective PV-generated electricity. These technologies have transitioned from the laboratory to the market place. Pilot production and first-time manufacturing are ramping up to higher capacity and enjoying a flood of venture-capital funding. CIGS solar cells and modules have achieved 19.5% and 13% efficiencies, respectively. Likewise, CdTe cells and modules have reached 16.5% and 10.2% efficiencies, respectively. Even higher efficiencies from the laboratory and from the manufacturing line are only a matter of time. Manufacturing-line yield continues to improve and is surpassing 85%. Long-term stability has been demonstrated for both technologies; however, some failures in the field have also been observed, emphasizing the critical need for understanding degradation mechanisms and packaging options. The long-term potential of the two technologies require R&D emphasis on science and engineering-based challenges to find solutions to achieve targeted cost-effective module performance, and in-field durability. Some of the challenges are common to both, e.g., in-situ process control and diagnostics, thinner absorber, understanding degradation mechanisms, protection from water vapor, and innovation in high-speed processing and module design. Other topics are specific to the technology, such as lower-cost and fast-deposition processes for CIGS, and improved back contact and voltage for CdTe devices.

  2. solar

    National Nuclear Security Administration (NNSA)

    2%2A en Solar power purchase for DOE laboratories http:nnsa.energy.govmediaroompressreleasessolarpower

  3. Photovoltaic Silicon Cell Basics | Department of Energy

    Energy Savers [EERE]

    Silicon Cell Basics Photovoltaic Silicon Cell Basics August 20, 2013 - 2:19pm Addthis Silicon-used to make some the earliest photovoltaic (PV) devices-is still the most popular material for solar cells. Silicon is also the second-most abundant element in the Earth's crust (after oxygen). However, to be useful as a semiconductor material in solar cells, silicon must be refined to a purity of 99.9999%. In single-crystal silicon, the molecular structure-which is the arrangement of atoms in the

  4. Method for fabricating silicon cells

    DOE Patents [OSTI]

    Ruby, D.S.; Basore, P.A.; Schubert, W.K.

    1998-08-11

    A process is described for making high-efficiency solar cells. This is accomplished by forming a diffusion junction and a passivating oxide layer in a single high-temperature process step. The invention includes the class of solar cells made using this process, including high-efficiency solar cells made using Czochralski-grown silicon. 9 figs.

  5. Method for fabricating silicon cells

    DOE Patents [OSTI]

    Ruby, Douglas S. (Albuquerque, NM); Basore, Paul A. (Albuquerque, NM); Schubert, W. Kent (Albuquerque, NM)

    1998-08-11

    A process for making high-efficiency solar cells. This is accomplished by forming a diffusion junction and a passivating oxide layer in a single high-temperature process step. The invention includes the class of solar cells made using this process, including high-efficiency solar cells made using Czochralski-grown silicon.

  6. Spheral Solar Power | Open Energy Information

    Open Energy Info (EERE)

    Place: Cambridge, Ontario, Canada Zip: N3E 1A9 Sector: Solar Product: Developing a manufacturing process for silicon solar cells in the form of silicon spheres bonded to aluminium...

  7. NREL: Learning - Solar Photovoltaic Technology Basics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Photovoltaic Technology Basics Photo of a large silicon solar array on a roof with a blue sky and trees in background. A large silicon solar array installed on the roof of a...

  8. Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon...

    Office of Scientific and Technical Information (OSTI)

    Hydrogenation of Dislocation- Limited Heteroepitaxial Silicon Solar Cells Preprint Michael L. Bolen, Sachit Grover, Charles W. Teplin, Howard M. Branz, and Paul Stradins National...

  9. Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon...

    Office of Scientific and Technical Information (OSTI)

    Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon Solar Cells: Preprint Bolen, M. L.; Grover, S.; Teplin, C. W.; Bobela, D.; Branz, H. M.; Stradins, P. 08 HYDROGEN; 14...

  10. RSI Silicon Products LLC | Open Energy Information

    Open Energy Info (EERE)

    startup which is developing a process for solar-grade silicon manufacture at low energy intensity, spinoff from MIT. Coordinates: 47.237806, -121.179542 Show Map...

  11. Advent Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc Jump to: navigation, search Name: Advent Solar Inc Place: Albuquerque, New Mexico Zip: 87106 Product: Albuquerque-based manufacturer of crystalline silicon PV cells and...

  12. Millinet Solar Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Millinet Solar Co Ltd Jump to: navigation, search Name: Millinet Solar Co Ltd Place: Daegu, Daegu, Korea (Republic) Product: Korean manufacturer of multicrystalline silicon PV...

  13. CSG Solar AG | Open Energy Information

    Open Energy Info (EERE)

    Germany Zip: 6766 Sector: Solar Product: Manufacture of solar modules based on Crystalline Silicon on Glass (CSG) technology Coordinates: 50.70348, 12.8498 Show Map...

  14. Sinonar Solar Sinonar Corp | Open Energy Information

    Open Energy Info (EERE)

    Sinonar Solar Sinonar Corp Jump to: navigation, search Name: Sinonar Solar (Sinonar Corp) Place: Miaoli, Taiwan Product: Sinonar corporation is an amorphous silicon cell...

  15. Solland Solar Energy BV | Open Energy Information

    Open Energy Info (EERE)

    Energy BV Jump to: navigation, search Name: Solland Solar Energy BV Place: Heerlen, Netherlands Zip: NL 6422RL Sector: Solar Product: Dutch manufacturer of crystalline silicon...

  16. Pacific Solar Pty Ltd | Open Energy Information

    Open Energy Info (EERE)

    to: navigation, search Name: Pacific Solar Pty Ltd Place: Botany, New South Wales, Australia Sector: Solar Product: Developed crystaline silicon on glass (CSG) technology...

  17. Best Solar Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Best Solar Co Ltd Jump to: navigation, search Name: Best Solar Co Ltd Place: Suzhou, Jiangsu Province, China Sector: Solar Product: Thin-film solar startup Best Solar was set up by...

  18. Yttria-stabilized zirconia buffered silicon to optimize in-plane electrical conductivity of [Ca{sub 2}CoO{sub 3}]{sub 0.62}[CoO{sub 2}] thin films

    SciTech Connect (OSTI)

    Kraus, T.; Griesser, A.; Klein, O.; Fischer, M.; Schreck, M.; Karl, H.

    2014-05-05

    The monolithic integration of thermoelectric generators and magnetoresistive functionality on the basis of misfit cobaltate [Ca{sub 2}CoO{sub 3}]{sub 0.62}[CoO{sub 2}] thin films into silicon technology is a prerequisite for their application in miniaturized electric circuits. Here, we report on [Ca{sub 2}CoO{sub 3}]{sub 0.62}[CoO{sub 2}] thin films grown by pulsed laser deposition on (001)-silicon with a thin epitaxial yttria-stabilized zirconia (YSZ) buffer layer. X-ray diffraction and cross-sectional high resolution transmission electron microscopy analysis reveal that high quality c-axis oriented heteroepitaxial [Ca{sub 2}CoO{sub 3}]{sub 0.62}[CoO{sub 2}] films with a 12-fold in-plane rotational symmetry can be grown, which exhibit remarkable lower electrical resistivity compared to those with random in-plane orientation. This result is explained by energetically preferred epitaxial growth directions of the pseudo hexagonal [CoO{sub 2}] sublayer in monoclinic [Ca{sub 2}CoO{sub 3}]{sub 0.62}[CoO{sub 2}] onto the cubic (001)-YSZ surface leading to a highly symmetric in-plane mutual orientation of the charge transporting CoO{sub 2} sublayer domains.

  19. Feasibility Study of Solar Photovoltaics on Landfills in Puerto Rico (Second Study)

    SciTech Connect (OSTI)

    Salasovich, J.; Mosey, G.

    2011-08-01

    This report presents the results of an assessment of the technical and economic feasibility of deploying a solar photovoltaics (PV) system on landfill sites in Puerto Rico. The purpose of this report is to assess the landfills with the highest potential for possible solar PV installation and estimate cost, performance, and site impacts of three different PV options: crystalline silicon (fixed tilt), crystalline silicon (single-axis tracking), and thin film (fixed tilt). The report outlines financing options that could assist in the implementation of a system. According to the site production calculations, the most cost-effective system in terms of return on investment is the thin-film fixed-tilt technology. The report recommends financing options that could assist in the implementation of such a system. The landfills and sites considered in this report were all determined feasible areas in which to implement solar PV systems.

  20. Two-Dimensional Measurement of n+-p Asymmetrical Junctions in Multicrystalline Silicon Solar Cells using AFM-Based Electrical Techniques with Nanometer Resolution

    SciTech Connect (OSTI)

    Jiang, C. S.; Heath, J. T.; Moutinho, H. R.; Li, J. V.; Al-Jassim, M. M.

    2011-01-01

    Lateral inhomogeneities of modern solar cells demand direct electrical imaging with nanometer resolution. We show that atomic force microscopy (AFM)-based electrical techniques provide unique junction characterizations, giving a two-dimensional determination of junction locations. Two AFM-based techniques, scanning capacitance microscopy/spectroscopy (SCM/SCS) and scanning Kelvin probe force microscopy (SKPFM), were significantly improved and applied to the junction characterizations of multicrystalline silicon (mc-Si) cells. The SCS spectra were taken pixel by pixel by precisely controlling the tip positions in the junction area. The spectra reveal distinctive features that depend closely on the position relative to the electrical junction, which allows us to indentify the electrical junction location. In addition, SKPFM directly probes the built-in potential over the junction area modified by the surface band bending, which allows us to deduce the metallurgical junction location by identifying a peak of the electric field. Our results demonstrate resolutions of 10-40 nm, depending on the techniques (SCS or SKPFM). These direct electrical measurements with nanometer resolution and intrinsic two-dimensional capability are well suited for investigating the junction distribution of solar cells with lateral inhomogeneities.

  1. Two-Dimensional Measurement of n+-p Asymmetrical Junctions in Multicrystalline Silicon Solar Cells Using AFM-Based Electrical Techniques with Nanometer Resolution: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Moutinho, H. R.; Li, J. V.; Al-Jassim, M. M.; Heath, J. T.

    2011-07-01

    Lateral inhomogeneities of modern solar cells demand direct electrical imaging with nanometer resolution. We show that atomic force microscopy (AFM)-based electrical techniques provide unique junction characterizations, giving a two-dimensional determination of junction locations. Two AFM-based techniques, scanning capacitance microscopy/spectroscopy (SCM/SCS) and scanning Kelvin probe force microscopy (SKPFM), were significantly improved and applied to the junction characterizations of multicrystalline silicon (mc-Si) cells. The SCS spectra were taken pixel by pixel by precisely controlling the tip positions in the junction area. The spectra reveal distinctive features that depend closely on the position relative to the electrical junction, which allows us to indentify the electrical junction location. In addition, SKPFM directly probes the built-in potential over the junction area modified by the surface band bending, which allows us to deduce the metallurgical junction location by identifying a peak of the electric field. Our results demonstrate resolutions of 10-40 nm, depending on the techniques (SCS or SKPFM). These direct electrical measurements with nanometer resolution and intrinsic two-dimensional capability are well suited for investigating the junction distribution of solar cells with lateral inhomogeneities.

  2. Magnolia Solar | Open Energy Information

    Open Energy Info (EERE)

    Magnolia Solar Jump to: navigation, search Name: Magnolia Solar Place: Woburn, Massachusetts Zip: 1801 Product: Massachusetts-based thin-film PV startup. Coordinates: 42.479195,...

  3. Shengrui Solar | Open Energy Information

    Open Energy Info (EERE)

    Name: Shengrui Solar Place: Hong Kong Product: Hong Kong headquartered company with thin-film PV production in China. References: Shengrui Solar1 This article is a stub....

  4. ITi Solar | Open Energy Information

    Open Energy Info (EERE)

    Boulder, Colorado Zip: 80303 Region: Rockies Area Sector: Solar Product: Developing thin-film solar that can be printed on an inkjet printer Website: www.itisolar.com...

  5. FTL Solar | Open Energy Information

    Open Energy Info (EERE)

    FTL Solar develops lightweight, flexible tensile structures embedded with thin-film solar cells. Coordinates: 30.267605, -97.742984 Show Map Loading map......

  6. The Silicon Mine | Open Energy Information

    Open Energy Info (EERE)

    produce solar grade polysilicon suitable for the production of wafers or as the base material for the manufacture of solar cells. References: The Silicon Mine1 This article is a...

  7. Thin Film Transistors On Plastic Substrates

    DOE Patents [OSTI]

    Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA); Sigmon, Thomas W. (Portola Valley, CA); Aceves, Randy C. (Livermore, CA)

    2004-01-20

    A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The silicon based thin film transistor produced by the process includes a low temperature substrate incapable of withstanding sustained processing temperatures greater than about 250.degree. C., an insulating layer on the substrate, a layer of silicon on the insulating layer having sections of doped silicon, undoped silicon, and poly-silicon, a gate dielectric layer on the layer of silicon, a layer of gate metal on the dielectric layer, a layer of oxide on sections of the layer of silicon and the layer of gate metal, and metal contacts on sections of the layer of silicon and layer of gate metal defining source, gate, and drain contacts, and interconnects.

  8. Amorphous silicon ionizing particle detectors

    DOE Patents [OSTI]

    Street, R.A.; Mendez, V.P.; Kaplan, S.N.

    1988-11-15

    Amorphous silicon ionizing particle detectors having a hydrogenated amorphous silicon (a--Si:H) thin film deposited via plasma assisted chemical vapor deposition techniques are utilized to detect the presence, position and counting of high energy ionizing particles, such as electrons, x-rays, alpha particles, beta particles and gamma radiation. 15 figs.

  9. Amorphous silicon ionizing particle detectors

    DOE Patents [OSTI]

    Street, Robert A. (Palo Alto, CA); Mendez, Victor P. (Berkeley, CA); Kaplan, Selig N. (El Cerrito, CA)

    1988-01-01

    Amorphous silicon ionizing particle detectors having a hydrogenated amorphous silicon (a--Si:H) thin film deposited via plasma assisted chemical vapor deposition techniques are utilized to detect the presence, position and counting of high energy ionizing particles, such as electrons, x-rays, alpha particles, beta particles and gamma radiation.

  10. 13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion, 10-13 August 2003, Vail, Colorado

    SciTech Connect (OSTI)

    Sopori, B.; Sinton, R.; Tan, T.; Swanson, D.

    2004-01-01

    The 13th Workshop discussion sessions addressed recent progress, critical issues in implementing new technologies, and the role of fundamental R&D in the growing PV industry. For the first time, we included a rump session, which was held on Sunday evening, August 10. This session included a panel of representatives, from various photovoltaic companies, who led a discussion of''R&D Challenges in Si PV.'' A special poster/presentation session was held on Monday evening, August 11, in which NREL/DOE subcontractors highlighted their results of research performed during the current subcontract period. This session served as a subcontract review. The workshop offered special sessions to discuss: (1) High-Efficiency Si Solar Cells, which reviewed progress made in implementing high-efficiency Si solar cell fabrication processes in the manufacturing environment; (2) Advanced Processing, as future potential approaches for making Si solar cells; (3) Commercial Issues, which addressed basic understanding behind recent processes that have been used by the PV industry; and (4) Automation and Equipment, to address capabilities and requirements of new manufacturing equipment.

  11. Silicone metalization

    DOE Patents [OSTI]

    Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter (Pleasanton, CA); Hamilton, Julie (Tracy, CA)

    2008-12-09

    A system for providing metal features on silicone comprising providing a silicone layer on a matrix and providing a metal layer on the silicone layer. An electronic apparatus can be produced by the system. The electronic apparatus comprises a silicone body and metal features on the silicone body that provide an electronic device.

  12. Silicone metalization

    DOE Patents [OSTI]

    Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter (Pleasanton, CA); Hamilton, Julie (Tracy, CA)

    2006-12-05

    A system for providing metal features on silicone comprising providing a silicone layer on a matrix and providing a metal layer on the silicone layer. An electronic apparatus can be produced by the system. The electronic apparatus comprises a silicone body and metal features on the silicone body that provide an electronic device.

  13. Apparatus for forming thin-film heterojunction solar cells employing materials selected from the class of I-III-VI.sub.2 chalcopyrite compounds

    DOE Patents [OSTI]

    Mickelsen, Reid A. (Bellevue, WA); Chen, Wen S. (Seattle, WA)

    1983-01-01

    Apparatus for forming thin-film, large area solar cells having a relatively high light-to-electrical energy conversion efficiency and characterized in that the cell comprises a p-n-type heterojunction formed of: (i) a first semiconductor layer comprising a photovoltaic active material selected from the class of I-III-VI.sub.2 chalcopyrite ternary materials which is vacuum deposited in a thin "composition-graded" layer ranging from on the order of about 2.5 microns to about 5.0 microns (.congruent.2.5 .mu.m to .congruent.5.0 .mu.m) and wherein the lower region of the photovoltaic active material preferably comprises a low resistivity region of p-type semiconductor material having a superimposed region of relatively high resistivity, transient n-type semiconductor material defining a transient p-n homojunction; and (ii), a second semiconductor layer comprising a low resistivity n-type semiconductor material wherein interdiffusion (a) between the elemental constituents of the two discrete juxtaposed regions of the first semiconductor layer defining a transient p-n homojunction layer, and (b) between the transient n-type material in the first semiconductor layer and the second n-type semiconductor layer, causes the transient n-type material in the first semiconductor layer to evolve into p-type material, thereby defining a thin layer heterojunction device characterized by the absence of voids, vacancies and nodules which tend to reduce the energy conversion efficiency of the system.

  14. Metallic Inks for Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-10-370

    SciTech Connect (OSTI)

    van Hest, M.

    2013-04-01

    This document describes the statement of work for National Renewable Energy Laboratory (NREL) as a subcontractor for Applied Nanotech, Inc. (ANI) for the Phase II SBIR contract with the Department of Energy to build silicon solar cells using non-contact printed, nanoparticle-based metallic inks. The conductive inks are based upon ANI's proprietary method for nanoparticle dispersion. The primary inks under development are aluminum for silicon solar cell back plane contacts and copper for top interdigitated contacts. The current direction of silicon solar cell technology is to use thinner silicon wafers. The reduction in wafer thickness reduces overall material usage and can increase efficiency. These thin silicon wafers are often very brittle and normal methods used for conductive feed line application, such as screen-printing, are detrimental. The Phase II program will be focused on materials development for metallic inks that can be applied to a silicon solar cell using non-contact methods. Uniform BSF (Back Surface Field) formation will be obtained by optimizing ink formulation and curing conditions to improve cell efficiency.

  15. Enhancement of oxidation resistance of graphite foams by polymer derived-silicon carbide coating for concentrated solar power applications

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kim, T.; Singh, D.; Singh, M.

    2015-05-01

    Graphite foam with extremely high thermal conductivity has been investigated to enhance heat transfer of latent heat thermal energy storage (LHTES) systems. However, the use of graphite foam for elevated temperature applications (>600 °C) is limited due to poor oxidation resistance of graphite. In the present study, oxidation resistance of graphite foam coated with silicon carbide (SiC) was investigated. A pre-ceramic polymer derived coating (PDC) method was used to form a SiC coating on the graphite foams. Post coating deposition, the samples were analyzed by scanning electron microscopy and energy dispersive spectroscopy. The oxidation resistance of PDC-SiC coating was quantifiedmore » by measuring the weight of the samples at several measuring points. The experiments were conducted under static argon atmosphere in a furnace. After the experiments, oxidation rates (%/hour) were calculated to predict the lifetime of the graphite foams. The experimental results showed that the PDC-SiC coating could prevent the oxidation of graphite foam under static argon atmosphere up to 900 °C.« less

  16. Enhancement of oxidation resistance of graphite foams by polymer derived-silicon carbide coating for concentrated solar power applications

    SciTech Connect (OSTI)

    Kim, T.; Singh, D.; Singh, M.

    2015-05-01

    Graphite foam with extremely high thermal conductivity has been investigated to enhance heat transfer of latent heat thermal energy storage (LHTES) systems. However, the use of graphite foam for elevated temperature applications (>600 C) is limited due to poor oxidation resistance of graphite. In the present study, oxidation resistance of graphite foam coated with silicon carbide (SiC) was investigated. A pre-ceramic polymer derived coating (PDC) method was used to form a SiC coating on the graphite foams. Post coating deposition, the samples were analyzed by scanning electron microscopy and energy dispersive spectroscopy. The oxidation resistance of PDC-SiC coating was quantified by measuring the weight of the samples at several measuring points. The experiments were conducted under static argon atmosphere in a furnace. After the experiments, oxidation rates (%/hour) were calculated to predict the lifetime of the graphite foams. The experimental results showed that the PDC-SiC coating could prevent the oxidation of graphite foam under static argon atmosphere up to 900 C.

  17. Solar Torx New Solar Ventures | Open Energy Information

    Open Energy Info (EERE)

    Torx New Solar Ventures Jump to: navigation, search Name: Solar Torx New Solar Ventures Place: Arizona Product: Set up in November 2005 to secure finance for a thin-film...

  18. High-Rate Fabrication of a-Si-Based Thin-Film Solar Cells Using Large-Area VHF PECVD Processes

    SciTech Connect (OSTI)

    Deng, Xunming; Fan, Qi Hua

    2011-12-31

    The University of Toledo (UT), working in concert with its a-Si-based PV industry partner Xunlight Corporation (Xunlight), has conducted a comprehensive study to develop a large-area (3ft x 3ft) VHF PECVD system for high rate uniform fabrication of silicon absorber layers, and the large-area VHF PECVD processes to achieve high performance a-Si/a-SiGe or a-Si/nc-Si tandem junction solar cells during the period of July 1, 2008 to Dec. 31, 2011, under DOE Award No. DE-FG36-08GO18073. The project had two primary goals: (i) to develop and improve a large area (3 ft 3 ft) VHF PECVD system for high rate fabrication of > = 8 /s a-Si and >= 20 /s nc-Si or 4 /s a-SiGe absorber layers with high uniformity in film thicknesses and in material structures. (ii) to develop and optimize the large-area VHF PECVD processes to achieve high-performance a-Si/nc-Si or a-Si/a-SiGe tandem-junction solar cells with >= 10% stable efficiency. Our work has met the goals and is summarized in Accomplishments versus goals and objectives.

  19. Cadmium-free junction fabrication process for CuInSe.sub.2 thin film solar cells

    DOE Patents [OSTI]

    Ramanathan, Kannan V.; Contreras, Miguel A.; Bhattacharya, Raghu N.; Keane, James; Noufi, Rommel

    1999-01-01

    The present invention provides an economical, simple, dry and controllable semiconductor layer junction forming process to make cadmium free high efficiency photovoltaic cells having a first layer comprised primarily of copper indium diselenide having a thin doped copper indium diselenide n-type region, generated by thermal diffusion with a group II(b) element such as zinc, and a halide, such as chlorine, and a second layer comprised of a conventional zinc oxide bilayer. A photovoltaic device according the present invention includes a first thin film layer of semiconductor material formed primarily from copper indium diselenide. Doping of the copper indium diselenide with zinc chloride is accomplished using either a zinc chloride solution or a solid zinc chloride material. Thermal diffusion of zinc chloride into the copper indium diselenide upper region creates the thin n-type copper indium diselenide surface. A second thin film layer of semiconductor material comprising zinc oxide is then applied in two layers. The first layer comprises a thin layer of high resistivity zinc oxide. The second relatively thick layer of zinc oxide is doped to exhibit low resistivity.

  20. EERE Success Story-Silicon Ink Technology Offers Path to Higher...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost EERE Success Story-Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower ...

  1. Xiamen Topunive Technology Co Ltd TP Solar | Open Energy Information

    Open Energy Info (EERE)

    Solar) Place: Xiamen, Fujian Province, China Zip: 361022 Sector: Solar Product: Produce thin-film PV module based flexible solar lighting system, portable and mobile power...

  2. SSC HHV Solar Technologies JV | Open Energy Information

    Open Energy Info (EERE)

    Technologies JV Place: Ontario, Canada Sector: Solar Product: Canada-based thin film solar panel manufacturing facility. References: SSC & HHV Solar Technologies JV1 This...

  3. Reducing the Cost of Solar Cells

    SciTech Connect (OSTI)

    Scanlon, B.

    2012-04-01

    Solar-powered electricity prices could soon approach those of power from coal or natural gas thanks to collaborative research with solar startup Ampulse Corporation at the National Renewable Energy Laboratory. Silicon wafers account for almost half the cost of today's solar photovoltaic panels, so reducing or eliminating wafer costs is essential to bringing prices down. Current crystalline silicon technology converts energy in a highly efficient manner; however, that technology is manufactured with processes that could stand some improvement. The industry needs a method that is less complex, creates less waste and uses less energy. First, half the refined silicon is lost as dust in the wafer-sawing process, driving module costs higher. Wafers are sawn off of large cylindrical ingots, or boules, of silicon. A typical 2-meter boule loses as many as 6,000 potential wafers during sawing. Second, the wafers produced are much thicker than necessary. To efficiently convert sunlight into electricity, the wafers need be only one-tenth the typical thickness. NREL, the Oak Ridge National Laboratory and Ampulse have partnered on an approach to eliminate this waste and dramatically lower the cost of the finished solar panels. By using a chemical vapor deposition process to grow the silicon on inexpensive foil, Ampulse is able to make the solar cells just thick enough to convert most of the solar energy into electricity. No more sawdust - and no more wasting refined silicon materials. NREL developed the technology to grow high-quality silicon and ORNL developed the metal foil that has the correct crystal structure to support that growth. Ampulse is installing a pilot manufacturing line in NREL's Process Development Integration Laboratory, where solar companies can work closely with lab scientists on integrated equipment to answer pressing questions related to their technology development, as well as rapidly overcoming R and D challenges and risk. NREL's program is focused on transformative innovation in the domestic PV industry. With knowledge and expertise acquired from the PDIL pilot production line tools, Ampulse plans to design a full-scale production line to accommodate long rolls of metal foil. The Ampulse process 'goes straight from pure silicon-containing gas to high-quality crystal silicon film,' said Brent Nelson, the operational manager for the Process Development Integration Laboratory. 'The advantage is you can make the wafer just as thin as you need it - 10 microns or less.' Most of today's solar cells are made out of wafer crystalline silicon, though thin-film cells made of more exotic elements such as copper, indium, gallium, arsenic, cadmium, tellurium and others are making a strong push into the market. The advantage of silicon is its abundance, because it is derived from sand. Silicon's disadvantage is that purifying it into wafers suitable for solar cells can be expensive and energy intensive. Manufacturers add carbon and heat to sand to produce metallurgical-grade silicon, which is useful in other industries, but not yet suitable for making solar cells. So this metallurgical-grade silicon is then converted to pure trichlorosilane (SiCl3) or silane (SiH4) gas. Typically, the purified gas is then converted to create a silicon feedstock at 1,000 degrees Celsius. This feedstock is melted at 1,414 C and recrystallized into crystal ingots that are finally sawed into wafers. The Ampulse method differs in that it eliminates the last two steps in the traditional process and works directly with the silane gas growing only the needed silicon right onto a foil substrate. A team of NREL scientists had developed a way to use a process called hot-wire chemical vapor deposition to thicken silicon wafers with near perfect crystal structure. Using a hot tungsten filament much like the one found in an incandescent light bulb, the silane gas molecules are broken apart and deposited onto the wafer using the chemical vapor deposition technique at about 700 C - a much lower temperature than needed to make the wafer. The hot filament dec

  4. Effect of Front-Side Silver Metallization on Underlying n+-p Junction in Multicrystalline Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Jiang, C. S.; Li, Z. G.; Moutinho, H. R.; Liang, L.; Ionkin, A.; Al-Jassim, M. M.

    2012-06-01

    We report on the effect of front-side Ag metallization on the underlying n+-p junction of multicrystalline Si solar cells. The junction quality beneath the contacts was investigated by characterizing the uniformities of the electrostatic potential and doping concentration across the junction, using scanning Kelvin probe force microscopy and scanning capacitance microscopy. We investigated cells with a commercial Ag paste (DuPont PV159) and fired at furnace setting temperatures of 800 degrees, 840 degrees, and 930 degrees C, which results in actual cell temperatures ~100 degrees C lower than the setting temperature and the three cells being under-, optimal-, and over-fired. We found that the uniformity of the junction beneath the Ag contact was significantly degraded by the over-firing, whereas the junction retained good uniformity with the optimal- and under-fire temperatures. Further, Ag crystallites with widely distributed sizes from <100 nm to several ?m were found at the Ag/Si interface of the over-fired cell. Large crystallites were imaged as protrusions into Si deeper than the junction depth. However, the junction was not broken down; instead, it was reformed on the entire front of the crystallite/Si interface. We propose a mechanism of the junction-quality degradation, based on emitter Si melting at the temperature around the Ag-Si eutectic point during firing, and subsequent recrystallization with incorporation of impurities in the Ag paste and with formation of crystallographic defects during quenching.

  5. High Efficiency Amorphous and Microcrystalline Silicon Based Double-Junction Solar Cells made with Very-High-Frequency Glow Discharge

    SciTech Connect (OSTI)

    Banerjee, Arindam

    2004-10-20

    We have achieved a total-area initial efficiency of 11.47% (active-area efficiency of 12.33%) on a-Si:H/?c-Si:H double-junction structure, where the intrinsic layer bottom cell was made in 50 minutes. On another device in which the bottom cell was made in 30 min, we achieved initial total-area efficiency of 10.58% (active-efficiency of 11.35%). We have shown that the phenomenon of ambient degradation of both ?c-Si:H single-junction and a-Si:H/?c-Si:H double-junction cells can be attributed to impurity diffusion after deposition. Optimization of the plasma parameters led to alleviation of the ambient degradation. Appropriate current matching between the top and bottom component cells has resulted in a stable total-area efficiency of 9.7% (active-area efficiency of 10.42%) on an a-Si:H/?c-Si:H double-junction solar cell in which the deposition time for the ?c-Si:H intrinsic layer deposition was of 30 min.

  6. Epitaxial growth of silicon for layer transfer

    DOE Patents [OSTI]

    Teplin, Charles; Branz, Howard M

    2015-03-24

    Methods of preparing a thin crystalline silicon film for transfer and devices utilizing a transferred crystalline silicon film are disclosed. The methods include preparing a silicon growth substrate which has an interface defining substance associated with an exterior surface. The methods further include depositing an epitaxial layer of silicon on the silicon growth substrate at the surface and separating the epitaxial layer from the substrate substantially along the plane or other surface defined by the interface defining substance. The epitaxial layer may be utilized as a thin film of crystalline silicon in any type of semiconductor device which requires a crystalline silicon layer. In use, the epitaxial transfer layer may be associated with a secondary substrate.

  7. Soitec SA Silicon on Insulator Technologies | Open Energy Information

    Open Energy Info (EERE)

    navigation, search Name: Soitec SA (Silicon on Insulator Technologies) Place: Bernin, France Zip: 38190 Product: Has an 'atomic scalpel' technology which allows extremely thin...

  8. Modeling of capacitance transients of thin-film solar cells: A valuable tool to gain information on perturbing layers or interfaces

    SciTech Connect (OSTI)

    Lauwaert, Johan Van Puyvelde, Lisanne; Vrielinck, Henk; Lauwaert, Jeroen; Thybaut, Joris W.

    2014-02-03

    Thin-film electronic and photovoltaic devices often comprise, in addition to the anticipated p-n junctions, additional non-ideal ohmic contacts between layers. This may give rise to additional signals in capacitance spectroscopy techniques that are not directly related to defects in the structure. In this paper, we present a fitting algorithm for transient signals arising from such an additional junction. The fitting results are in excellent agreement with the diode characteristics extracted from static measurements on individual components. Finally, the algorithm is applied for determining the barriers associated with anomalous signals reported for selected CuIn{sub 1x}Ga{sub x}Se{sub 2} and CdTe solar cells.

  9. Breakthrough Cutting Technology Promises to Reduce Solar Costs

    Broader source: Energy.gov [DOE]

    Silicon Genesis advancing the field of solar energy by developing a process that will virtually eliminate all waste when cutting materials needed to implement solar technology.

  10. Sinocome Solar aka Perfect Field Investment | Open Energy Information

    Open Energy Info (EERE)

    Solar aka Perfect Field Investment Jump to: navigation, search Name: Sinocome Solar (aka Perfect Field Investment) Place: China Product: Chinese manufacturer of amorphous silicon...

  11. Enhancement of current collection in epitaxial lift-off InAs/GaAs quantum dot thin film solar cell and concentrated photovoltaic study

    SciTech Connect (OSTI)

    Sogabe, Tomah Shoji, Yasushi; Tamayo, Efrain; Okada, Yoshitaka; Mulder, Peter; Schermer, John

    2014-09-15

    We report the fabrication of a thin film InAs/GaAs quantum dot solar cell (QD cell) by applying epitaxial lift-off (ELO) approach to the GaAs substrate. We confirmed significant current collection enhancement (?0.91?mA/cm{sup 2}) in the ELO-InAs QD cell within the wavelength range of 700?nm900?nm when compared to the ELO-GaAs control cell. This is almost six times of the sub-GaAs bandgap current collection (?0.16?mA/cm{sup 2}) from the wavelength range of 900?nm and beyond, we also confirmed the ELO induced resonance cavity effect was able to increase the solar cell efficiency by increasing both the short circuit current and open voltage. The electric field intensity of the resonance cavity formed in the ELO film between the Au back reflector and the GaAs front contact layer was analyzed in detail by finite-differential time-domain (FDTD) simulation. We found that the calculated current collection enhancement within the wavelength range of 700?nm900?nm was strongly influenced by the size and shape of InAs QD. In addition, we performed concentrated light photovoltaic study and analyzed the effect of intermediate states on the open voltage under varied concentrated light intensity for the ELO-InAs QD cell.

  12. Solar Notion Inc | Open Energy Information

    Open Energy Info (EERE)

    search Name: Solar Notion Inc Place: Menlo Park, California Zip: 94025 Product: Startup with an undisclosed type of thin-film PV technology. References: Solar Notion Inc1...

  13. Advanced Solar Photonics | Open Energy Information

    Open Energy Info (EERE)

    Advanced Solar Photonics Place: Lake Mary, Florida Zip: 32746 Product: Florida-based thin film PV module manufacturer. References: Advanced Solar Photonics1 This article is...

  14. Moncada Solar Equipment | Open Energy Information

    Open Energy Info (EERE)

    search Name: Moncada Solar Equipment Place: Italy Product: Developer and manufacturer of thin-film modules. References: Moncada Solar Equipment1 This article is a stub. You can...

  15. FTL Solar LLC | Open Energy Information

    Open Energy Info (EERE)

    Sector: Solar Product: Creator of flexible, tensile structures integrated with thin film solar cells Website: www.ftlsolar.com Coordinates: 40.6498136, -73.9475554 Show Map...

  16. Sanyo Eneos Solar Inc | Open Energy Information

    Open Energy Info (EERE)

    Solar Inc Jump to: navigation, search Name: Sanyo Eneos Solar Inc. Place: Tokyo, Tokyo, Japan Product: Thin-film joint venture between Sanyo Electric and Nippon Oil. References:...

  17. Silicon on insulator self-aligned transistors

    DOE Patents [OSTI]

    McCarthy, Anthony M.

    2003-11-18

    A method for fabricating thin-film single-crystal silicon-on-insulator (SOI) self-aligned transistors. Standard processing of silicon substrates is used to fabricate the transistors. Physical spaces, between the source and gate, and the drain and gate, introduced by etching the polysilicon gate material, are used to provide connecting implants (bridges) which allow the transistor to perform normally. After completion of the silicon substrate processing, the silicon wafer is bonded to an insulator (glass) substrate, and the silicon substrate is removed leaving the transistors on the insulator (glass) substrate. Transistors fabricated by this method may be utilized, for example, in flat panel displays, etc.

  18. Method of fabricating high-efficiency Cu(In,Ga)(Se,S){sub 2} thin films for solar cells

    DOE Patents [OSTI]

    Noufi, R.; Gabor, A.M.; Tuttle, J.R.; Tennant, A.L.; Contreras, M.A.; Albin, D.S.; Carapella, J.J.

    1995-08-15

    A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S){sub 2} comprises depositing a first layer of (In,Ga){sub x} (Se,S){sub y} followed by depositing just enough Cu+(Se,S) or Cu{sub x} (Se,S) to produce the desired slightly Cu-poor material. In a variation, most, but not all, (about 90 to 99%) of the (In,Ga){sub x} (Se,S){sub y} is deposited first, followed by deposition of all the Cu+(Se,S) or Cu{sub x} (Se,S) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 to 10%) of the (In,Ga){sub x} (Se,S){sub y} is first deposited as a seed layer, followed by deposition of all of the Cu+(Se,S) or Cu{sub x} (Se,S) to make a very Cu-rich mixture, and then followed deposition of the remainder of the (In,Ga){sub x} (Se,S){sub y} to go slightly Cu-poor in the final Cu(In,Ga)(Se,S){sub 2} thin film. 5 figs.

  19. Method of fabricating high-efficiency Cu(In,Ga)(SeS).sub.2 thin films for solar cells

    DOE Patents [OSTI]

    Noufi, Rommel; Gabor, Andrew M.; Tuttle, John R.; Tennant, Andrew L.; Contreras, Miguel A.; Albin, David S.; Carapella, Jeffrey J.

    1995-01-01

    A process for producing a slightly Cu-poor thin film of Cu(In,Ga)(Se,S).sub.2 comprises depositing a first layer of (In,Ga).sub.x (Se,S).sub.y followed by depositing just enough Cu+(Se,S) or Cu.sub.x (Se,S) to produce the desired slightly Cu-poor material. In a variation, most, but not all, (about 90 to 99%) of the (In,Ga).sub.x (Se,S).sub.y is deposited first, followed by deposition of all the Cu+(Se,S) or Cu.sub.x (Se,S) to go near stoichiometric, possibly or even preferably slightly Cu-rich, and then in turn followed by deposition of the remainder (about 1 to 10%) of the (In,Ga).sub.x (Se,S).sub.y to end with a slightly Cu-poor composition. In yet another variation, a small portion (about 1 to 10%) of the (In,Ga).sub.x (Se,S).sub.y is first deposited as a seed layer, followed by deposition of all of the Cu+(Se,S) or Cu.sub.x (Se,S) to make a very Cu-rich mixture, and then followed deposition of the remainder of the (In,Ga).sub.x (Se,S).sub.y to go slightly Cu-poor in the final Cu(In,Ga)(Se,S).sub.2 thin film.

  20. Silica substrate or portion formed from oxidation of monocrystalline silicon

    DOE Patents [OSTI]

    Matzke, Carolyn M.; Rieger, Dennis J.; Ellis, Robert V.

    2003-07-15

    A method is disclosed for forming an inclusion-free silica substrate using a monocrystalline silicon substrate as the starting material and oxidizing the silicon substrate to convert it entirely to silica. The oxidation process is performed from both major surfaces of the silicon substrate using a conventional high-pressure oxidation system. The resulting product is an amorphous silica substrate which is expected to have superior etching characteristics for microfabrication than conventional fused silica substrates. The present invention can also be used to convert only a portion of a monocrystalline silicon substrate to silica by masking the silicon substrate and locally thinning a portion the silicon substrate prior to converting the silicon portion entirely to silica. In this case, the silica formed by oxidizing the thinned portion of the silicon substrate can be used, for example, as a window to provide optical access through the silicon substrate.

  1. Solar collector

    SciTech Connect (OSTI)

    Wilhelm, W.G.

    1982-05-04

    The field of this invention is solar collectors, and more particularly, the invention pertains to a flat plate collector that employs high performance thin films. The solar collector of this invention overcomes several problems in this field, such as excessive hardware, cost and reliability, and other prior art drawbacks outlined in the specification. In the preferred form, the apparatus features a substantially rigid planar frame. A thin film window is bonded to one planar side of the frame. An absorber of laminate construction is comprised of two thin film layers that are sealed perimetrically. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. Absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

  2. Sierra Solar Power Inc | Open Energy Information

    Open Energy Info (EERE)

    Power Inc Place: Sunnyvale, California Zip: 94086 Product: Developer of an undisclosed thin-film PV technology and headquartered in Silicon Valley, the company plans to...

  3. OptiSolar Inc | Open Energy Information

    Open Energy Info (EERE)

    Inc Place: Hayward, California Zip: 94544 Product: Project developer, site banker and thin-film silicon technology developer. Assets substantially disbanded in March 2009....

  4. Development of large-area monolithically integrated Silicon-Film photovoltaic modules. Annual subcontract report, 16 November 1991--31 December 1992

    SciTech Connect (OSTI)

    Rand, J.A.; Cotter, J.E.; Ingram, A.E.; Ruffins, T.R.; Shreve, K.P.; Hall, R.B.; Barnett, A.M.

    1993-06-01

    This report describes work to develop Silicon-Film{trademark} Product III into a low-cost, stable solar cell for large-scale terrestrial power applications. The Product III structure is a thin (< 100-{mu}m) polycrystalline layer of silicon on a durable, insulating, ceramic substrate. The insulating substrate allows the silicon layer to be isolated and metallized to form a monolithically interconnected array of solar cells. High efficiency is achievable with the use of light trapping and a passivated back surface. The long-term goal for the product is a 1200-cm{sup 2}, 18%-efficient, monolithic array. The short-term objectives are to improve material quality and to fabricate 100 cm{sup 2} monolithically interconnected solar cell arrays. Low minority-carrier diffusion length in the silicon film and series resistance in the interconnected device structure are presently limiting device performance. Material quality is continually improving through reduced impurity contamination. Metallization schemes, such as a solder-dipped interconnection process, have been developed that will allow low-cost production processing and minimize R{sub s} effects. Test data for a nine-cell device (16 cm{sup 2}) indicated a V{sub oc} of 3.72 V. These first-reported monolithically interconnected multicrystalline silicon-on-ceramic devices show low shunt conductance (< 0.1 mA/cm{sup 2}) due to limited conduction through the ceramic and no process-related metallization shunts.

  5. Trench process and structure for backside contact solar cells with polysilicon doped regions

    DOE Patents [OSTI]

    De Ceuster, Denis; Cousins, Peter John; Smith, David D

    2013-05-28

    A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.

  6. Trench process and structure for backside contact solar cells with polysilicon doped regions

    DOE Patents [OSTI]

    De Ceuster, Denis (Woodside, CA); Cousins, Peter John (Menlo Park, CA); Smith, David D. (Campbell, CA)

    2010-12-14

    A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.

  7. Trench process and structure for backside contact solar cells with polysilicon doped regions

    DOE Patents [OSTI]

    De Ceuster, Denis; Cousins, Peter John; Smith, David D

    2014-03-18

    A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.

  8. Simulation and optimization of ultra thin photovoltaics.

    SciTech Connect (OSTI)

    Cruz-Campa, Jose Luis

    2010-12-01

    Sandia National Laboratories (SNL) conducts pioneering research and development in Micro-Electro-Mechanical Systems (MEMS) and solar cell research. This dissertation project combines these two areas to create ultra-thin small-form-factor crystalline silicon (c-Si) solar cells. These miniature solar cells create a new class of photovoltaics with potentially novel applications and benefits such as dramatic reductions in cost, weight and material usage. At the beginning of the project, unusually low efficiencies were obtained in the research group. The intention of this research was thus to investigate the main causes of the low efficiencies through simulation, design, fabrication, and characterization. Commercial simulation tools were used to find the main causes of low efficiency. Once the causes were identified, the results were used to create improved designs and build new devices. In the simulations, parameters were varied to see the effect on the performance. The researched parameters were: resistance, wafer lifetime, contact separation, implant characteristics (size, dosage, energy, ratio between the species), contact size, substrate thickness, surface recombination, and light concentration. Out of these parameters, it was revealed that a high quality surface passivation was the most important for obtaining higher performing cells. Therefore, several approaches for enhancing the passivation were tried, characterized, and tested on cells. In addition, a methodology to contact and test the performance of all the cells presented in the dissertation under calibrated light was created. Also, next generation cells that could incorporate all the optimized layers including the passivation was designed, built, and tested. In conclusion, through this investigation, solar cells that incorporate optimized designs and passivation schemes for ultrathin solar cells were created for the first time. Through the application of the methods discussed in this document, the efficiency of the solar cells increased from below 1% to 15% in Microsystems Enabled Photovoltaic (MEPV) devices.

  9. 6N Silicon Inc | Open Energy Information

    Open Energy Info (EERE)

    Inc Jump to: navigation, search Name: 6N Silicon Inc Place: Mississauga, Ontario, Canada Zip: L5T 1E6 Sector: Solar Product: Canadian manufactuer of upgraded metallurgical...

  10. B Solar Ltd | Open Energy Information

    Open Energy Info (EERE)

    B-Solar Ltd Place: Raanana, Israel Product: Israeli manufacturer of bifacial silicon cells and modules. Coordinates: 32.182579, 34.87014 Show Map Loading map......

  11. Solar Energy Italia Spa | Open Energy Information

    Open Energy Info (EERE)

    Spa Jump to: navigation, search Name: Solar Energy Italia Spa Place: Prato, Italy Zip: 59100 Product: Designersmanufactures of complete PV power systems using silicon modules from...

  12. Picture of the Week: Perovskite solar power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    that exhibit solar conversion efficiencies comparable to those of silicon, the current gold standard. This image shows the kind of high-efficiency perovskite crystals regularly...

  13. Formosun Solar Corp | Open Energy Information

    Open Energy Info (EERE)

    Corp. Place: Hsinchu County, Taiwan Zip: 303-51 Sector: Solar Product: Thin-film solar cell producer based in Taiwan. References: Formosun Solar Corp.1 This article is a stub....

  14. AxunTek Solar Energy | Open Energy Information

    Open Energy Info (EERE)

    AxunTek Solar Energy Jump to: navigation, search Name: AxunTek Solar Energy Place: Taiwan Sector: Solar Product: Taiwan-based CIGS thin film solar cell producer. References:...

  15. Validating Solar Innovation to Power

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    investor confidence in novel technical approaches. The RTCs can accommodate multiple solar technologies, including crystalline and thin-film modules: fixed-tilt and tracker...

  16. ICP Solar Technologies Inc | Open Energy Information

    Open Energy Info (EERE)

    Zip: H3N 1W5 Sector: Solar Product: Manufactures amorphous silicon solar PV cells, and battery chargers using these cells. Coordinates: 45.512293, -73.554407 Show Map Loading...

  17. Award-Winning Etching Process Cuts Solar Cell Costs (Revised) (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

    The NREL "black silicon" nanocatalytic wet-chemical etch is an inexpensive, one-step method to minimize reflections from crystalline silicon solar cells. The technology enables high-efficiency solar cells without the use of expensive antireflection coatings.

  18. Monolithically interconnected GaAs solar cells: A new interconnection technology for high voltage solar cell output

    SciTech Connect (OSTI)

    Dinetta, L.C.; Hannon, M.H.

    1995-10-01

    Photovoltaic linear concentrator arrays can benefit from high performance solar cell technologies being developed at AstroPower. Specifically, these are the integration of thin GaAs solar cell and epitaxial lateral overgrowth technologies with the application of monolithically interconnected solar cell (MISC) techniques. This MISC array has several advantages which make it ideal for space concentrator systems. These are high system voltage, reliable low cost monolithically formed interconnections, design flexibility, costs that are independent of array voltage, and low power loss from shorts, opens, and impact damage. This concentrator solar cell will incorporate the benefits of light trapping by growing the device active layers over a low-cost, simple, PECVD deposited silicon/silicon dioxide Bragg reflector. The high voltage-low current output results in minimal 12R losses while properly designing the device allows for minimal shading and resistance losses. It is possible to obtain open circuit voltages as high as 67 volts/cm of solar cell length with existing technology. The projected power density for the high performance device is 5 kW/m for an AMO efficiency of 26% at 1 5X. Concentrator solar cell arrays are necessary to meet the power requirements of specific mission platforms and can supply high voltage power for electric propulsion systems. It is anticipated that the high efficiency, GaAs monolithically interconnected linear concentrator solar cell array will enjoy widespread application for space based solar power needs. Additional applications include remote man-portable or ultra-light unmanned air vehicle (UAV) power supplies where high power per area, high radiation hardness and a high bus voltage or low bus current are important. The monolithic approach has a number of inherent advantages, including reduced cost per interconnect and increased reliability of array connections. There is also a high potential for a large number of consumer products.

  19. Polycrystalline thin-film cadmium telluride solar cells fabricated by electrodeposition. Annual subcontract report, 20 March 1992--19 March 1993

    SciTech Connect (OSTI)

    Trefny, J.U.; Furtak, T.E.; Wada, N.; Williamson, D.L.; Kim, D.

    1993-08-01

    This report describes progress during the first year of a 3-year program at Colorado School of Mines, based upon earlier studies performed by Ametek Corporation, to develop specific layers of the Ametek n-i-p structure as well as additional studies of several transparent conducting oxides. Thin films of ZnO and ZnO:Al were deposited under various conditions. For the n-layer of the Ametek structure, a dip-coating method was developed for the deposition of CdS films. The authors also present data on the characterization of these films by X-ray diffraction, Raman spectroscopy, scanning tunneling microscopy, small-angle X-ray scattering, and other techniques. They made progress in the electrodeposition of the CdTe i-layer of the Ametek structure. They developed appropriate electrochemical baths and are beginning to understand the role of the many experimental parameters that must be controlled to obtain high-quality films of this material. They explored the possibility of using an electrochemical process for fabricating the ZnTe p-layer. Some preliminary success was achieved, and this step will be pursued in the next phase. Finally, they fabricated a number of ``dot`` solar cells with the structure glass/SnO{sub 2}/CdS/CdTe/Au. Several cells with efficiencies in the range of 5%-6% were obtained, and they are confident, given recent progress, that cells with efficiencies in excess of 10% will be achieved in the near future.

  20. Unique Quantum Effect Found in Silicon Nanocrystals - News Releases | NREL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unique Quantum Effect Found in Silicon Nanocrystals Quantum Dot Materials May Improve Efficiency of Silicon Solar Cells July 24, 2007 Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), collaborating with Innovalight, Inc., have shown that a new and important effect called Multiple Exciton Generation (MEG) occurs efficiently in silicon nanocrystals. MEG results in the formation of more than one electron per absorbed photon. Silicon is the dominant