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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 ...

  2. 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;

  3. 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.

  4. 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.

  5. 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.

  6. Amorphous silicon Schottky barrier solar cells incorporating a thin insulating layer and a thin doped layer

    DOE Patents [OSTI]

    Carlson, David E.

    1980-01-01

    Amorphous silicon Schottky barrier solar cells which incorporate a thin insulating layer and a thin doped layer adjacent to the junction forming metal layer exhibit increased open circuit voltages compared to standard rectifying junction metal devices, i.e., Schottky barrier devices, and rectifying junction metal insulating silicon devices, i.e., MIS devices.

  7. 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.

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

    SciTech Connect (OSTI)

    Martini, R.; Kepa, J.; Stesmans, A.; Debucquoy, M.; Depauw, V.; Gonzalez, M.; Gordon, I.; Poortmans, J.

    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 μs 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 μm of material, the lifetime of the foil increases by more than a factor of 4.5, reaching a value of 461 μs. 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.

  9. Silicon solar cell assembly

    DOE Patents [OSTI]

    Burgess, Edward L.; Nasby, Robert D.; Schueler, Donald G.

    1979-01-01

    A silicon solar cell assembly comprising a large, thin silicon solar cell bonded to a metal mount for use when there exists a mismatch in the thermal expansivities of the device and the mount.

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

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

    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 ...

  11. Schottky barrier amorphous silicon solar cell with thin doped region adjacent metal Schottky barrier

    DOE Patents [OSTI]

    Carlson, David E.; Wronski, Christopher R.

    1979-01-01

    A Schottky barrier amorphous silicon solar cell incorporating a thin highly doped p-type region of hydrogenated amorphous silicon disposed between a Schottky barrier high work function metal and the intrinsic region of hydrogenated amorphous silicon wherein said high work function metal and said thin highly doped p-type region forms a surface barrier junction with the intrinsic amorphous silicon layer. The thickness and concentration of p-type dopants in said p-type region are selected so that said p-type region is fully ionized by the Schottky barrier high work function metal. The thin highly doped p-type region has been found to increase the open circuit voltage and current of the photovoltaic device.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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).

  19. 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.

  20. 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.

  1. 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. ...

  2. 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.

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

    SciTech Connect (OSTI)

    Junghanns, Marcus; Plentz, Jonathan Andrä, Gudrun; Gawlik, Annett; Höger, 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 μm 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.

  4. 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.

  5. Progress in thin film solar photovoltaic technologies

    SciTech Connect (OSTI)

    Ullal, H.S.; Zweibel, K.; Mitchell, R.L. )

    1991-01-01

    This paper focuses on the rapid recent advances made by thin film solar cell technologies, namely, amorphous silicon, copper indium diselenide, and cadmium telluride. It also indicates the several advantages of thin films. Various consumer products and power applications using thin film solar cells are also discussed. The increasing interest among the utilities for PV system applications is also elucidated.

  6. 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.

  7. 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..

  8. 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.

  9. 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 µm 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 = 1.57×10{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.

  10. 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.

  11. 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.

  12. 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 μm thickness gives maximum efficiency up to 24 % whereas same efficiency is achieved with the use of three bilayers grating based solar cell of 30 μm 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 μm cell thicknesses respectively. These presented designing efforts would be helpful to design and realize new generation of solar cells.

  13. Progress in thin film solar photovoltaic technologies

    SciTech Connect (OSTI)

    Ullal, H.S.; Zweibel, K.

    1989-12-01

    This paper focuses on the rapid recent advances made by thin film solar cell technologies, namely, amorphous silicon, copper indium diselenide, and cadmium telluride. It also indicates the several advantages of thin films. Various consumer products and power applications using thin film solar cells are also discussed. The increasing interest among the utilities for PV system applications is also elucidated. 29 refs., 8 figs., 3 tabs.

  14. Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon Solar Cells:

    Office of Scientific and Technical Information (OSTI)

    Preprint (Conference) | SciTech Connect Conference: Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon Solar Cells: Preprint Citation Details In-Document Search Title: Hydrogenation of Dislocation-Limited Heteroepitaxial Silicon Solar Cells: Preprint Post-deposition hydrogenation by remote plasma significantly improves performance of heteroepitaxial silicon solar cells. Heteroepitaxial deposition of thin crystal silicon on sapphire for photovoltaics (PV) is an excellent model

  15. 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...

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. NREL: Energy Analysis - Crystalline Silicon and Thin Film Photovoltaic

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

    Results - Life Cycle Assessment Harmonization Crystalline Silicon and Thin Film Photovoltaic Results - Life Cycle Assessment Harmonization Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics (Fact Sheet) Cover of the Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics factsheet Download the Fact Sheet Over the last 30 years, hundreds of life cycle assessments (LCAs) have been conducted and published for a variety of residential and utility-scale solar photovoltaic (PV)

  2. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Carlson, David E.

    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.

  3. Solar Silicon Wafers

    Office of Energy Efficiency and Renewable Energy (EERE)

    This photograph features Hao-Chih Yuan, a scientist at the National Renewable Energy Laboratory (NREL). He is reflected in a highly reflective untreated silicone wafer (left) compared to a silicone...

  4. 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%.

  5. Compensated amorphous silicon solar cell

    DOE Patents [OSTI]

    Devaud, Genevieve

    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.

  6. 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...

  7. The origin of white luminescence from silicon oxycarbide thin...

    Office of Scientific and Technical Information (OSTI)

    origin of white luminescence from silicon oxycarbide thin films Citation Details In-Document Search Title: The origin of white luminescence from silicon oxycarbide thin films ...

  8. Cermet layer for amorphous silicon solar cells

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1979-01-01

    A transparent high work function metal cermet forms a Schottky barrier in a Schottky barrier amorphous silicon solar cell and adheres well to the P+ layer in a PIN amorphous silicon solar cell.

  9. 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:...

  10. 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...

  11. Method for processing silicon solar cells

    DOE Patents [OSTI]

    Tsuo, Y. Simon; Landry, Marc D.; Pitts, John R.

    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.

  12. 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.

  13. Laser wafering for silicon solar.

    SciTech Connect (OSTI)

    Friedmann, Thomas Aquinas; Sweatt, William C.; Jared, Bradley Howell

    2011-03-01

    Current technology cuts solar Si wafers by a wire saw process, resulting in 50% 'kerf' loss when machining silicon from a boule or brick into a wafer. We want to develop a kerf-free laser wafering technology that promises to eliminate such wasteful wire saw processes and achieve up to a ten-fold decrease in the g/W{sub p} (grams/peak watt) polysilicon usage from the starting polysilicon material. Compared to today's technology, this will also reduce costs ({approx}20%), embodied energy, and green-house gas GHG emissions ({approx}50%). We will use short pulse laser illumination sharply focused by a solid immersion lens to produce subsurface damage in silicon such that wafers can be mechanically cleaved from a boule or brick. For this concept to succeed, we will need to develop optics, lasers, cleaving, and high throughput processing technologies capable of producing wafers with thicknesses < 50 {micro}m with high throughput (< 10 sec./wafer). Wafer thickness scaling is the 'Moore's Law' of silicon solar. Our concept will allow solar manufacturers to skip entire generations of scaling and achieve grid parity with commercial electricity rates. Yet, this idea is largely untested and a simple demonstration is needed to provide credibility for a larger scale research and development program. The purpose of this project is to lay the groundwork to demonstrate the feasibility of laser wafering. First, to design and procure on optic train suitable for producing subsurface damage in silicon with the required damage and stress profile to promote lateral cleavage of silicon. Second, to use an existing laser to produce subsurface damage in silicon, and third, to characterize the damage using scanning electron microscopy and confocal Raman spectroscopy mapping.

  14. 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.

  15. 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.

  16. Comparison of Thin Epitaxial Film Silicon Photovoltaics Fabricated...

    Office of Scientific and Technical Information (OSTI)

    Silicon Photovoltaics Fabricated on Monocrystalline and Polycrystalline Seed Layers on Glass Citation Details In-Document Search Title: Comparison of Thin Epitaxial Film Silicon ...

  17. Amorphous silicon solar cell allowing infrared transmission

    DOE Patents [OSTI]

    Carlson, David E.

    1979-01-01

    An amorphous silicon solar cell with a layer of high index of refraction material or a series of layers having high and low indices of refraction material deposited upon a transparent substrate to reflect light of energies greater than the bandgap energy of the amorphous silicon back into the solar cell and transmit solar radiation having an energy less than the bandgap energy of the amorphous silicon.

  18. 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.

  19. 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.

  20. Tandem junction amorphous silicon solar cells

    DOE Patents [OSTI]

    Hanak, Joseph J.

    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.

  1. Solar cell with silicon oxynitride dielectric layer

    SciTech Connect (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.

  2. Thin film solar energy collector

    DOE Patents [OSTI]

    Aykan, Kamran; Farrauto, Robert J.; Jefferson, Clinton F.; Lanam, Richard D.

    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.

  3. 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.

  4. Intermediate Bandgap Solar Cells From Nanostructured Silicon

    SciTech Connect (OSTI)

    Black, Marcie

    2014-10-30

    This project aimed to demonstrate increased electronic coupling in silicon nanostructures relative to bulk silicon for the purpose of making high efficiency intermediate bandgap solar cells using silicon. To this end, we formed nanowires with controlled crystallographic orientation, small diameter, <111> sidewall faceting, and passivated surfaces to modify the electronic band structure in silicon by breaking down the symmetry of the crystal lattice. We grew and tested these silicon nanowires with <110>-growth axes, which is an orientation that should produce the coupling enhancement.

  5. 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.

  6. Fabricating solar cells with silicon nanoparticles

    SciTech Connect (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.

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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)...

  15. 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...

  16. 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...

  17. 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,...

  18. 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.

  19. Inverted amorphous silicon solar cell utilizing cermet layers

    DOE Patents [OSTI]

    Hanak, Joseph J.

    1979-01-01

    An amorphous silicon solar cell incorporating a transparent high work function metal cermet incident to solar radiation and a thick film cermet contacting the amorphous silicon opposite to said incident surface.

  20. 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.

  1. High-efficiency silicon heterojunction solar cells: Status and perspectives

    SciTech Connect (OSTI)

    De Wolf, S.; Geissbuehler, J.; Loper, P.; Martin de Nicholas, S.; Seif, J.; Tomasi, A.; Ballif, C.

    2015-05-11

    Silicon heterojunction technology (HJT) uses silicon thin-film deposition techniques to fabricate photovoltaic devices from mono-crystalline silicon wafers (c-Si). This enables energy-conversion efficiencies above 21 %, also at industrial-production level. In this presentation we review the present status of this technology and point out recent trends. We first discuss how the properties of thin hydrogenated amorphous silicon (a-Si:H) films can be exploited to fabricate passivating contacts, which is the key to high- efficiency HJT solar cells. Such contacts enable very high operating voltages, approaching the theoretical limits, and yield small temperature coefficients. With this approach, an increasing number of groups are reporting devices with conversion efficiencies well over 20 % on both-sides contacted n-type cells, Panasonic leading the field with 24.7 %. Exciting results have also been obtained on p-type wafers. Despite these high voltages, important efficiency gains can still be made in fill factor and optical design. This requires improved understanding of carrier transport across device interfaces and reduced parasitic absorption in HJT solar cells. For the latter, several strategies can be followed: Short-wavelength losses can be reduced by replacing the front a-Si:H films with wider-bandgap window layers, such as silicon alloys or even metal oxides. Long- wavelength losses are mitigated by introducing new high-mobility TCO’s such as hydrogenated indium oxide, and also by designing new rear reflectors. Optical shadow losses caused by the front metallization grid are significantly reduced by replacing printed silver electrodes with fine-line plated copper contacts, leading also to possible cost advantages. The ultimate approach to minimize optical losses is the implementation of back-contacted architectures, which are completely devoid of grid shadow losses and parasitic absorption in the front layers can be minimized irrespective of electrical

  2. High-efficiency silicon heterojunction solar cells: Status and perspectives

    SciTech Connect (OSTI)

    De Wolf, S.

    2015-04-27

    Silicon heterojunction technology (HJT) uses silicon thin-film deposition techniques to fabricate photovoltaic devices from mono-crystalline silicon wafers (c-Si). This enables energy-conversion efficiencies above 21 %, also at industrial-production level. In this presentation we review the present status of this technology and point out recent trends. We first discuss how the properties of thin hydrogenated amorphous silicon (a-Si:H) films can be exploited to fabricate passivating contacts, which is the key to high- efficiency HJT solar cells. Such contacts enable very high operating voltages, approaching the theoretical limits, and yield small temperature coefficients. With this approach, an increasing number of groups are reporting devices with conversion efficiencies well over 20 % on n-type wafers, Panasonic leading the field with 24.7 %. Exciting results have also been obtained on p-type wafers. Despite these high voltages, important efficiency gains can still be made in fill factor and optical design. This requires improved understanding of carrier transport across device interfaces and reduced parasitic absorption in HJT solar cells. For the latter, several strategies can be followed: Short- wavelength losses can be reduced by replacing the front a-Si:H films with wider-bandgap window layers, such as silicon alloys or even metal oxides. Long-wavelength losses are mitigated by introducing new high-mobility TCO’s such as hydrogenated indium oxide, and also by designing new rear reflectors. Optical shadow losses caused by the front metalisation grid are significantly reduced by replacing printed silver electrodes with fine-line plated copper contacts, leading also to possible cost advantages. The ultimate approach to minimize optical losses is the implementation of back-contacted architectures, which are completely devoid of grid shadow losses and parasitic absorption in the front layers can be minimized irrespective of electrical transport requirements. The

  3. Metal electrode for amorphous silicon solar cells

    DOE Patents [OSTI]

    Williams, Richard

    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.

  4. Indium oxide/n-silicon heterojunction solar cells

    DOE Patents [OSTI]

    Feng, Tom; Ghosh, Amal K.

    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%.

  5. 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

  6. 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.

  7. Thin-Film Photovoltaics on Solar House

    Broader source: Energy.gov [DOE]

    In this photograph, people are reflected on Team Germany's window louvers with integrated thin-film copper indium gallium selenide (CIGS) cells during the U.S. Department of Energy Solar Decathlon...

  8. 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.

  9. 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.

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

    Office of Energy Efficiency and Renewable Energy (EERE)

    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...

  11. Radiation resistance of thin-film solar cells for space photovoltaic power

    SciTech Connect (OSTI)

    Woodyard, J.R.; Landis, G.A.

    1991-01-01

    Copper indium diselenide, cadmium telluride, and amorphous silicon alloy solar cells have achieved noteworthy performance and are currently being studied for space power applications. Cadmium sulfide cells had been the subject of much effort but are no longer considered for space applications. A review is presented of what is known about the radiation degradation of thin film solar cells in space. Experimental cadmium telluride and amorphous silicon alloy cells are reviewed. Damage mechanisms and radiation induced defect generation and passivation in the amorphous silicon alloy cell are discussed in detail due to the greater amount of experimental data available.

  12. Amorphous silicon materials and solar cells

    SciTech Connect (OSTI)

    Stafford, B.L. )

    1991-01-01

    An International Meeting on Stability of Amorphous Silicon Materials and Solar Cells was held in Denver, CO on February 20--22, 1991. The main objectives of the meeting were to bring to light-and stimulate discussion on-recent advances in (1) understanding the underlying mechanisms of light-induced instability and (2) engineering approaches to stable solar cells. Several of the experimental and theoretical papers presented here, particularly those regarding low-hydrogen-content materials, give cause for optimism that the performance may finally be yielding to worldwide concerted efforts to understand and mitigate it. The four main topics discussed are modeling metastability, experimental data and model verification, materials studies, and solar cell studies.

  13. Techniques of Nanoscale Silicon Texturing of Solar Cells - Energy...

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

    Technology Marketing SummarySandia National Laboratories has created a technology that produces an antireflective (matte) surface on a silicon photovoltaic solar cell. The process ...

  14. 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...

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

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

    Building Energy Efficiency Building Energy ... Return to Search Low Cost, High Efficiency Tandem Silicon Solar Cells and LEDs ... gaps will lead to efficient power conversion. ...

  16. 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.

  17. 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...

  18. Metal catalyst technique for texturing silicon solar cells

    DOE Patents [OSTI]

    Ruby, Douglas S.; Zaidi, Saleem H.

    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.

  19. 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

  20. Thin film absorber for a solar collector

    DOE Patents [OSTI]

    Wilhelm, William G.

    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.

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

    DOE Patents [OSTI]

    Pankove, Jacques I.; Wu, Chung P.

    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.

  2. Substrate for thin silicon solar cells

    DOE Patents [OSTI]

    Ciszek, Theodore F.

    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.

  3. 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.

  4. 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.

    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.

  5. 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.

  6. 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.

  7. 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...

  8. 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 ... Being a solar energy enthusiast, he suggested that the investi- gation include solar ...

  9. Process development for high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Gee, J.M.; Basore, P.A.; Buck, M.E.; Ruby, D.S.; Schubert, W.K.; Silva, B.L.; Tingley, J.W.

    1991-01-01

    Fabrication of high-efficiency silicon solar cells in an industrial environment requires a different optimization than in a laboratory environment. Strategies are presented for process development of high-efficiency silicon solar cells, with a goal of simplifying technology transfer into an industrial setting. The strategies emphasize the use of statistical experimental design for process optimization, and the use of baseline processes and cells for process monitoring and quality control. 8 refs.

  10. 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 oxide–plasma 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.

  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

    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.

  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 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.

  14. 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

  15. Formation of thin-film resistors on silicon substrates

    DOE Patents [OSTI]

    Schnable, George L.; Wu, Chung P.

    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.

  16. Copper doped polycrystalline silicon solar cell

    DOE Patents [OSTI]

    Lovelace, Alan M. Administrator of the National Aeronautics and Space; Koliwad, Krishna M.; Daud, Taher

    1981-01-01

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

  17. 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...

  18. Overview and Challenges of Thin Film Solar Electric Technologies

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

    and Challenges 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. 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.

  20. NREL Achieves World Record Performance For Thin Film Solar Cell...

    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 ...

  1. 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.

  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. 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

  8. Amorphous Silicon Carbide Passivating Layers to Enable Higher Processing Temperature in Crystalline Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Boccard, Mathieu; Holman, Zachary

    2015-04-06

    "Very efficient crystalline silicon (c-Si) solar cells have been demonstrated when thin layers of intrinsic and doped hydrogenated amorphous silicon (a-Si:H) are used for passivation and carrier selectivity in a heterojunction device. One limitation of this device structure is the (parasitic) absorption in the front passivation/collection a-Si:H layers; another is the degradation of the a-Si:H-based passivation upon temperature, limiting the post-processes to approximately 200°C thus restricting the contacting possibilities and potential tandem device fabrication. To alleviate these two limitations, we explore the potential of amorphous silicon carbide (a-SiC:H), a widely studied material in use in standard a-Si:H thin-film solar cells, which is known for its wider bandgap, increased hydrogen content and stronger hydrogen bonding compared to a-Si:H. We study the surface passivation of solar-grade textured n-type c-Si wafers for symmetrical stacks of 10-nm-thick intrinsic a-SiC:H with various carbon content followed by either p-doped or n-doped a-Si:H (referred to as i/p or i/n stacks). For both doping types, passivation (assessed through carrier lifetime measurements) is degraded by increasing the carbon content in the intrinsic a-SiC:H layer. Yet, this hierarchy is reversed after annealing at 350°C or more due to drastic passivation improvements upon annealing when an a-SiC:H layer is used. After annealing at 350°C, lifetimes of 0.4 ms and 2.0 ms are reported for i/p and i/n stacks, respectively, when using an intrinsic a-SiC:H layer with approximately 10% of carbon (initial lifetimes of 0.3 ms and 0.1 ms, respectively, corresponding to a 30% and 20-fold increase, respectively). For stacks of pure a-Si:H material the lifetimes degrade from 1.2 ms and 2.0 ms for i/p and i/n stacks, respectively, to less than 0.1 ms and 1.1 ms (12-fold and 2-fold decrease, respectively). For complete solar cells using pure a-Si:H i/p and i/n stacks, the open-circuit voltage (Voc

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

    Office of Scientific and Technical Information (OSTI)

    Conference: Thin Silicon MEMS Contact-Stress Sensor Citation Details In-Document Search ... and exhibits good stability over time with no loss of calibration with load cycling. ...

  10. 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.

  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. 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...

  13. 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...

  14. 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.

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

    Office of Scientific and Technical Information (OSTI)

    Conference: Thin Silicon MEMS Contact-Stress Sensor Citation Details In-Document Search Title: Thin Silicon MEMS Contact-Stress Sensor This 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

  16. 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%.

  17. 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%.

  18. Researchers Growing Silicon Films for Solar Cells

    Broader source: Energy.gov [DOE]

    This photograph features Chaz Teplin, left, and Howard Branz, right, scientists at the National Renewable Energy Laboratory. They use a hot-wire chemical vapor deposition system to grow silicon...

  19. 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.

  20. 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.

  1. 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.

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

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

    Although its current market share is small, in the last several years the solar cell ... systems decreased from the current price of approximately 16,000-25,000. One way ...

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

    DOE Patents [OSTI]

    Feng, Tom; Ghosh, Amal K.

    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%.

  4. 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)

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

    DOE Patents [OSTI]

    Weiner, Kurt H.

    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.

  6. 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.

  7. High-efficiency solar cells using HEM silicon

    SciTech Connect (OSTI)

    Khattak, C.P.; Schmid, F.; Schubert, W.K.

    1994-12-31

    Developments in Heat Exchanger Method (HEM) technology for production of multicrystalline silicon ingot production have led to growth of larger ingots (55 cm square cross section) with lower costs and reliability in production. A single reusable crucible has been used to produce 18 multicrystalline 33 cm square cross section 40 kg ingots, and capability to produce 44 cm ingots has been demonstrated. Large area solar cells of 16.3% (42 cm{sup 2}) and 15.3% (100 cm{sup 2}) efficiency have been produced without optimization of the material production and the solar cell processing.

  8. 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.

  9. 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.

  10. 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.

  11. Modeling of Silicon Heterojunction Solar Cells

    SciTech Connect (OSTI)

    Luppina, P.; Lugli, P.; Goodnick, S.

    2015-06-14

    Here we present modeling results on crystalline Si/amorphous Si (a-Si) heterojunction solar cells using Sentaurus including various models for defect states in the a-Si barriers, as well as explicit models for the ITO emitter contact. We investigate the impact of the band offsets and barrier heights of the a-Si/c-Si interface, particularly in terms of the open circuit voltage. It is also shown that the solar cell performance is sensitively dependent on the quality of the a-Si in terms of defect states and their distribution, particularly on the emitter side. Finally, we have investigate the role of tunneling and thermionic emission across the heterointerface in terms of transport from the Si to the ITO contact layer

  12. 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.

  13. 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.

  14. Silicon Ink Technology Offers Path to Higher Efficiency Solar Cells at Lower Cost

    Broader source: Energy.gov [DOE]

    EERE supported the development of the first liquid silicon on the market that offers a novel path to producing more efficient solar cells at lower cost.

  15. 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.

  16. 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.

  17. Thin-Film Solar Cell Manufacturing

    Broader source: Energy.gov [DOE]

    In this b-roll, thin-film photovoltaic cells are manufactured and deployed in Arizona. Steps shown in the manufacturing process include the screen printing of conductive material onto laminated...

  18. Delaminations of thin layers by high dose hydrogen ion implantation in silicon. Formation of thin silicon on insulator silicon layers

    SciTech Connect (OSTI)

    Hara, Tohru; Onda, Takayuki; Kakizaki, Yasuo; Oshima, Sotaro; Kitamura, Taira; Kajiyama, Kenji; Yoneda, Tomoaki; Sekine, Kohei; Inoue, Morio

    1996-08-01

    The delamination of a thin layer from a Si wafer by high dose H{sup +} implantation has been studied. This process is applicable to the manufacture of Si on insulator wafers. Hydrogen ions are implanted into (100) p-Si through a 100 nm thick oxide layer at 100 keV with doses of 1.0 {times} 10{sup 16} and 1.0 {times} 10{sup 17} ion/cm{sup 2}. The implanted layer is measured by 1.5 MeV He{sup +} Rutherford backscattering spectrometry aligned spectra and by cross-sectional transmission electron microscopy after annealing. With annealing at 600 C, delamination of the Si layer, which occurred parallel to the surface, could be observed clearly at a depth of 0.85 {micro}m for a dose of 1.0 {times} 10{sup 17} ion/cm{sup 2}. The gap of the split Si layer is 20--30 nm wide. The roughness of the split layer surface is 7.5 nm. Point defects at the split layer surface decreased with annealing at high temperatures.

  19. 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.

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

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; EFFICIENCY; ENERGY CONVERSION; SOLAR CELLS; THIN FILMS ...

  1. 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...

  2. CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and...

    Office of Scientific and Technical Information (OSTI)

    CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and Accomplishments Citation Details In-Document Search Title: CIGS Thin-Film Solar Cell Research at NREL: FY04 Results and ...

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

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

    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 ...

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

    DOE Patents [OSTI]

    McKee, Rodney A.; Walker, Frederick Joseph

    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.

  5. 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....

  6. Spectral and temperature correction of silicon photovoltaic solar radiation detectors

    SciTech Connect (OSTI)

    Michalsky, J.J.; Perez, R.; Harrison, L. ); LeBaron, B.A. )

    1991-01-01

    Silicon photovoltaic sensors are an inexpensive alternative to standard thermopile sensors for the measurement of solar radiation. However, their temperature and spectral response render them less accurate for global horizontal irradiance and unsuitable for direct beam and diffuse horizontal irradiance unless they can be reliably corrected. A correction procedure for the rotating shadowband radiometer, which measures all three components, based on a three-way parameterization of the solar position and sky conditions is proposed. After correction, root-mean-square errors for the global and diffuse horizontal irradiance and the direct normal irradiance are about 10, 12, and 13 W/m{sup 2} in comparison with coincident, 5-minute thermopile measurements. While the numerical results are specific to the rotating shadowband instrument, the correction algorithm should apply universally.

  7. 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

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

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

    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

  9. 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.

  10. 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.

  11. 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.

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

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

    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 configurations. APPROACH In

  13. Light trapping in thin-film solar cells measured by Raman spectroscopy

    SciTech Connect (OSTI)

    Ledinský, M.; Moulin, E.; Bugnon, G.; Meillaud, F.; Ballif, C.; Ganzerová, K.; Vetushka, A.; Fejfar, A.

    2014-09-15

    In this study, Raman spectroscopy is used as a tool to determine the light-trapping capability of textured ZnO front electrodes implemented in microcrystalline silicon (μc-Si:H) solar cells. Microcrystalline silicon films deposited on superstrates of various roughnesses are characterized by Raman micro-spectroscopy at excitation wavelengths of 442 nm, 514 nm, 633 nm, and 785 nm, respectively. The way to measure quantitatively and with a high level of reproducibility the Raman intensity is described in details. By varying the superstrate texture and with it the light trapping in the μc-Si:H absorber layer, we find significant differences in the absolute Raman intensity measured in the near infrared wavelength region (where light trapping is relevant). A good agreement between the absolute Raman intensity and the external quantum efficiency of the μc-Si:H solar cells is obtained, demonstrating the validity of the introduced method. Applications to thin-film solar cells, in general, and other optoelectronic devices are discussed.

  14. 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.

  15. X-ray Study Reveals How Silver-to-Silicon Contacts Form for Solar Cells |

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

    Stanford Synchrotron Radiation Lightsource X-ray Study Reveals How Silver-to-Silicon Contacts Form for Solar Cells Saturday, April 30, 2016 Solar energy must be one of the primary energy sources as society transitions away from predominantly fossil fuels based economy. Currently, the overwhelming majority (>90%) of the photovoltaic (PV) market consists of silicon solar cells. While relatively inexpensive, this technology depends predominately on a screen-printed silver electrical

  16. National solar technology roadmap: Film-silicon PV

    SciTech Connect (OSTI)

    Keyes, Brian

    2007-06-01

    Silicon photovoltaic (PV) technologies are addressed in two different technology roadmaps: Film-Silicon PV and Wafer-Silicon PV. This Film-Silicon PV roadmap applies to all silicon-film technologies that rely on a supporting substrate such as glass, polymer, aluminum, stainless steel, or metallurgical-grade silicon. Such devices typically use amorphous, nanocrystalline, fine-grained polycrystalline, or epitaxial silicon layers that are 1–20 μm thick.

  17. 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.

  18. 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.

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

    SciTech Connect (OSTI)

    Guha, Subhendu; Yang, Chi-Chung; Ovshinsky, Stanford R.

    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.

  20. 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.

  1. 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.

  2. 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.

  3. 22.5% efficient silicon heterojunction solar cell with molybdenum oxide hole collector

    SciTech Connect (OSTI)

    Geissbühler, Jonas Werner, Jérémie; Martin de Nicolas, Silvia; Hessler-Wyser, Aïcha; Tomasi, Andrea; Niesen, Bjoern; De Wolf, Stefaan; Barraud, Loris; Despeisse, Matthieu; Nicolay, Sylvain; Ballif, Christophe

    2015-08-24

    Substituting the doped amorphous silicon films at the front of silicon heterojunction solar cells with wide-bandgap transition metal oxides can mitigate parasitic light absorption losses. This was recently proven by replacing p-type amorphous silicon with molybdenum oxide films. In this article, we evidence that annealing above 130 °C—often needed for the curing of printed metal contacts—detrimentally impacts hole collection of such devices. We circumvent this issue by using electrodeposited copper front metallization and demonstrate a silicon heterojunction solar cell with molybdenum oxide hole collector, featuring a fill factor value higher than 80% and certified energy conversion efficiency of 22.5%.

  4. 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...

  5. 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...

  6. 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

  7. Comment on “Towards high efficiency thin-film crystalline silicon solar cells: The roles of light trapping and non-radiative recombinations” [J. Appl. Phys. 115, 094501 (2014)

    SciTech Connect (OSTI)

    Abenante, L.

    2015-01-14

    In the above paper, an analytical approach including a new solution to the differential diffusion equation in illuminated quasi-neutral regions (QNR) is exploited to calculate the short-circuit current density (J{sub sc}), open-circuit voltage (V{sub oc}), fill factor (FF), and efficiency (η) of light-trapping (LT) c-Si solar cells with a given structure. Comparisons with numerical results calculated by the Silvaco ATLAS device simulator in the same LT cells show that the analytical results are systematically overestimated. According to the authors, the inaccuracies in J{sub sc}, V{sub oc}, and η are due to the fact that assuming ideal collection from space-charge region (SCR) and using the superposition approximation introduce systematic errors into analytical models. In this comment, an analytical approach using reported solutions to the transport equations in QNR and SCR, where ideal collection from SCR is assumed and the superposition approximation is used, is shown to agree with both the Silvaco and PC1d numerical approaches in calculating J{sub sc}, V{sub oc}, and η, in the same LT devices as considered in the commented paper. Reasons for the inaccuracies detected in the commented paper are suggested.

  8. Hot wire deposited hydrogenated amorphous silicon solar cells

    SciTech Connect (OSTI)

    Mahan, A.H.; Iwaniczko, E.; Nelson, B.P.; Reedy, R.C. Jr.; Crandall, R.S.

    1996-05-01

    This paper details the results of a study in which low H content, high deposition rate hot wire (HW) deposited amorphous silicon (a-Si:H) has been incorporated into a substrate solar cell. The authors find that the treatment of the top surface of the HW i layer while it is being cooled from its high deposition temperature is crucial to device performance. They present data concerning these surface treatments, and correlate these treatments with Schottky device performance. The authors also present first generation HW n-i-p solar cell efficiency data, where a glow discharge (GD) {mu}c-Si(p) layer was added to complete the partial devices. No light trapping layer was used to increase the device Jsc. Their preliminary investigations have yielded efficiencies of up to 6.8% for a cell with a 4000 {Angstrom} thick HW i-layer, which degrade less than 10% after a 900 hour light soak. The authors suggest avenues for further improvement of their devices.

  9. Hot wire deposited hydrogenated amorphous silicon solar cells

    SciTech Connect (OSTI)

    Mahan, A.H.; Iwaniczko, E.; Nelson, B.P.; Reedy, R.C., Jr.; Unold, T.; Crandall, R.S.; Guha, S.; Yang, J. |

    1997-02-01

    This paper details the results of a study in which low H content, high deposition rate hot wire (HW) deposited amorphous silicon (a-Si:H) has been incorporated into a substrate solar cell. We find that the treatment of the top surface of the HW i-layer while it is cooled from its high deposition temperature is crucial to device performance. We present data concerning these surface treatments, and correlate these treatments with Schottky device performance. We also present first generation HW n-i-p solar cell data, where a glow discharge (GD) {mu}c-Si(p) layer completes the partial devices. No light trapping layer is used to increase the device Jsc. Our preliminary results yield efficiencies of up to 6.8{percent} for a cell with a 4000 {Angstrom} thick HW i-layer, which degrade less than 10{percent} after a 900h AM1 light soak. We suggest areas for further improvement of our devices. {copyright} {ital 1997 American Institute of Physics.}

  10. Hot wire deposited hydrogenated amorphous silicon solar cells

    SciTech Connect (OSTI)

    Mahan, A.H.; Iwaniczko, E.; Nelson, B.P.; Reedy, R.C. Jr.; Crandall, R.S.; Guha, S.; Yang, J.

    1996-09-01

    This paper details the results of a study in which low H content, high deposition rate hot wire (HW) deposited amorphous silicon (a-Si:H) has been incorporated into a substrate solar cell. The authors find that the treatment of the top surface of the HW i layer while it is being cooled from its high deposition temperature is crucial to device performance. They present data concerning these surface treatments, and they correlate these treatments with Schottky device performance. They also present first generation HW n-i-p solar cell efficiency data, where a glow discharge (GD) {mu}c-Si(p) layer was added to complete the partial devices. No light trapping layer was used to increase the device Jsc. The preliminary investigations have yielded efficiencies of up to 6.8% for a cell with a 4,000 {angstrom} thick HW i-layer, which degrade less than 10% after a 900 hour light soak. They suggest avenues for further improvement of the devices.

  11. The effects of concentrated ultraviolet light on high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Ruby, D.S.; Schubert, W.K.

    1991-01-01

    The importance of stability in the performance of solar cells is clearly recognized as fundamental. Some of the highest efficiency silicon solar cells demonstrated to date, such as the Point Contact solar cell and the Passivated Emitter solar cell, rely upon the passivation of cell surfaces in order to minimize recombination, which reduces cell power output. Recently, it has been shown that exposure to ultraviolet (UV) light of wavelengths present in the terrestrial solar spectrum can damage a passivating silicon-oxide interface and increase recombination. In this study, we compared the performance of Point Contact and Passivated Emitter solar cells after exposure to UV light. We also examined the effect of UV exposure on oxide-passivated silicon wafers. We found that current Passivated Emitter designs are stable at both one-sun and under concentrated sunlight. The evolution of Point Contact concentrator cell performance shows a clear trend towards more stable cells. 15 refs., 18 figs.

  12. 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

  13. Hybrid emitter all back contact solar cell

    DOE Patents [OSTI]

    Loscutoff, Paul; Rim, Seung

    2016-04-12

    An all back contact solar cell has a hybrid emitter design. The solar cell has a thin dielectric layer formed on a backside surface of a single crystalline silicon substrate. One emitter of the solar cell is made of doped polycrystalline silicon that is formed on the thin dielectric layer. The other emitter of the solar cell is formed in the single crystalline silicon substrate and is made of doped single crystalline silicon. The solar cell includes contact holes that allow metal contacts to connect to corresponding emitters.

  14. GaP/Silicon Tandem Solar Cell with Extended Temperature Range - Energy

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

    Innovation Portal Vehicles and Fuels Vehicles and Fuels Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search GaP/Silicon Tandem Solar Cell with Extended Temperature Range NASA Glenn Research Center (http://www.nasa.gov/centers/glenn/home/index.html) National Aeronautics and Space Administration Contact NASA About This Technology Technology Marketing SummaryNASA Glenn Research Center (GRC) innovators have developed unique, tandem photovoltaic cells (or "solar

  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. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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....

  2. 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,...

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

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

    Maximum Efficiency (SLME) is a new and calculable selection metric to identify new andor improved photovoltaic (PV) absorber candidate materials for thin- film solar cells. ...

  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. 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

  6. 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.

  7. Hot wire deposited hydrogenated amorphous silicon solar cells

    SciTech Connect (OSTI)

    Mahan, A.H.; Nelson, B.P.; Iwaniczko, E.; Wang, Q.; Molenbroek, E.C.; Asher, S.E.; Reedy, R.C. Jr.; Crandall, R.S.

    1996-01-01

    This paper details preliminary results obtained in incorporating low H content, high substrate temperature hot wire (HW) deposited amorphous silicon material into a substrate solar cell structure. By necessity, since the learning curve for this complete structure involves metal/{ital n}-{ital i}/Schottky barrier structure optimization, a large part of the results are focused on this (partial) structure. We have found that the treatment of the top surface of the HW {ital i} layer during cooling is crucial to device performance. Without any particular attention paid to the treatment of this surface while the sample is cooling from its high deposition temperature, a significant amount of H diffuses out of the sample during the cooling process, particularly near the surface, resulting in devices with very poor photovoltaic properties. By designing a surface treatment to address this problem, we have been able to deposit HW Schottky structures with device characteristics as good as the best glow discharge devices produced in our laboratory. We present data concerning these surface treatments, and how they influence the H content at the {ital i}/Pd interface. {copyright} {ital 1996 American Institute of Physics.}

  8. Properties of boron-doped thin films of polycrystalline silicon

    SciTech Connect (OSTI)

    Merabet, Souad

    2013-12-16

    The properties of polycrystalline-silicon films deposited by low pressure chemical vapor deposition and doped heavily in situ boron-doped with concentration level of around 2×10{sup 20}cm{sup −3} has been studied. Their properties are analyzed using electrical and structural characterization means by four points probe resistivity measurements and X-ray diffraction spectra. The thermal-oxidation process are performed on sub-micron layers of 200nm/c-Si and 200nm/SiO{sub 2} deposited at temperatures T{sub d} ranged between 520°C and 605°C and thermally-oxidized in dry oxygen ambient at 945°C. Compared to the as-grown resistivity with silicon wafers is known to be in the following sequence <ρ{sub 200nm/c−Si}> < <ρ{sub 200nm/SiO2}> and <ρ{sub 520}> < <ρ{sub 605}>. The measure X-ray spectra is shown, that the Bragg peaks are marked according to the crystal orientation in the film deposited on bare substrates (poly/c-Si), for the second series of films deposited on bare oxidized substrates (poly/SiO{sub 2}) are clearly different.

  9. 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; Hernández, José 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.

  10. 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.

  11. Efficient nanorod-based amorphous silicon solar cells with advanced light trapping

    SciTech Connect (OSTI)

    Kuang, Y.; Lare, M. C. van; Polman, A.; Veldhuizen, L. W.; Schropp, R. E. I.; Rath, J. K.

    2015-11-14

    We present a simple, low-cost, and scalable approach for the fabrication of efficient nanorod-based solar cells. Templates with arrays of self-assembled ZnO nanorods with tunable morphology are synthesized by chemical bath deposition using a low process temperature at 80 °C. The nanorod templates are conformally coated with hydrogenated amorphous silicon light absorber layers of 100 nm and 200 nm thickness. An initial efficiency of up to 9.0% is achieved for the optimized design. External quantum efficiency measurements on the nanorod cells show a substantial photocurrent enhancement both in the red and the blue parts of the solar spectrum. Key insights in the light trapping mechanisms in these arrays are obtained via a combination of three-dimensional finite-difference time-domain simulations, optical absorption, and external quantum efficiency measurements. Front surface patterns enhance the light incoupling in the blue, while rear side patterns lead to enhanced light trapping in the red. The red response in the nanorod cells is limited by absorption in the patterned Ag back contact. With these findings, we develop and experimentally realize a further advanced design with patterned front and back sides while keeping the Ag reflector flat, showing significantly enhanced scattering from the back reflector with reduced parasitic absorption in the Ag and thus higher photocurrent generation. Many of the findings in this work can serve to provide insights for further optimization of nanostructures for thin-film solar cells in a broad range of materials.

  12. 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.

  13. 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.

  14. Titanium dioxide/silicon hole-blocking selective contact to enable double-heterojunction crystalline silicon-based solar cell

    SciTech Connect (OSTI)

    Nagamatsu, Ken A. Man, Gabriel; Jhaveri, Janam; Berg, Alexander H.; Kahn, Antoine; Wagner, Sigurd; Sturm, James C.; Avasthi, Sushobhan; Sahasrabudhe, Girija; Schwartz, Jeffrey

    2015-03-23

    In this work, we use an electron-selective titanium dioxide (TiO{sub 2}) heterojunction contact to silicon to block minority carrier holes in the silicon from recombining at the cathode contact of a silicon-based photovoltaic device. We present four pieces of evidence demonstrating the beneficial effect of adding the TiO{sub 2} hole-blocking layer: reduced dark current, increased open circuit voltage (V{sub OC}), increased quantum efficiency at longer wavelengths, and increased stored minority carrier charge under forward bias. The importance of a low rate of recombination of minority carriers at the Si/TiO{sub 2} interface for effective blocking of minority carriers is quantitatively described. The anode is made of a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) heterojunction to silicon which forms a hole selective contact, so that the entire device is made at a maximum temperature of 100 °C, with no doping gradients or junctions in the silicon. A low rate of recombination of minority carriers at the Si/TiO{sub 2} interface is crucial for effective blocking of minority carriers. Such a pair of complementary carrier-selective heterojunctions offers a path towards high-efficiency silicon solar cells using relatively simple and near-room temperature fabrication techniques.

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

    DOE Patents [OSTI]

    Carey, Paul G.; Smith, Patrick M.

    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.

  16. 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 ...

  17. Method for fabricating pixelated silicon device cells

    SciTech Connect (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. Beyond Silicon: Cutting the Costs of Solar Power

    DOE R&D Accomplishments [OSTI]

    Ahlberg, Liz

    2011-04-15

    New method of fabricating semiconductors from gallium arsenide promises more affordable solar power, improved semiconductor devices.

  19. 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.

  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. 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.

  2. 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)

  3. 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......

  4. Size effects on the thermal conductivity of amorphous silicon thin films

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

    Thomas Edwin Beechem; Braun, Jeffrey L.; Baker, Christopher H.; Elahi, Miraz; Artyushkova, Kateryna; Norris, Pamela M.; Leseman, Zayd Chad; Gaskins, John T.; Hopkins, Patrick E.; Giri, Ashutosh

    2016-04-01

    In this study, we investigate thickness-limited size effects on the thermal conductivity of amorphous silicon thin films ranging from 3 to 1636 nm grown via sputter deposition. While exhibiting a constant value up to ~100 nm, the thermal conductivity increases with film thickness thereafter. The thickness dependence we demonstrate is ascribed to boundary scattering of long wavelength vibrations and an interplay between the energy transfer associated with propagating modes (propagons) and nonpropagating modes (diffusons). A crossover from propagon to diffuson modes is deduced to occur at a frequency of ~1.8 THz via simple analytical arguments. These results provide empirical evidencemore » of size effects on the thermal conductivity of amorphous silicon and systematic experimental insight into the nature of vibrational thermal transport in amorphous solids.« less

  5. 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.

  6. 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 Deputy 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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 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.

  14. Evaluation of transition metal oxide as carrier-selective contacts for silicon heterojunction solar cells

    SciTech Connect (OSTI)

    Ding, L.; Boccard, Matthieu; Holman, Zachary; Bertoni, M.

    2015-04-06

    "Reducing light absorption in the non-active solar cell layers, while enabling the extraction of the photogenerated minority carriers at quasi-Fermi levels are two key factors to improve current generation and voltage, and therefore efficiency of silicon heterojunction solar devices. To address these two critical aspects, transition metal oxide materials have been proposed as alternative to the n- and p-type amorphous silicon used as electron and hole selective contacts, respectively. Indeed, transition metal oxides such as molybdenum oxide, titanium oxide, nickel oxide or tungsten oxide combine a wide band gap typically over 3 eV with a band structure and theoretical band alignment with silicon that results in high transparency to the solar spectrum and in selectivity for the transport of only one carrier type. Improving carrier extraction or injection using transition metal oxide has been a topic of investigation in the field of organic solar cells and organic LEDs; from these pioneering works a lot of knowledge has been gained on materials properties, ways to control these during synthesis and deposition, and their impact on device performance. Recently, the transfer of some of this knowledge to silicon solar cells and the successful application of some metal oxide to contact heterojunction devices have gained much attention. In this contribution, we investigate the suitability of various transition metal oxide films (molybdenum oxide, titanium oxide, and tungsten oxide) deposited either by thermal evaporation or sputtering as transparent hole or electron selective transport layer for silicon solar cells. In addition to systematically characterize their optical and structural properties, we use photoemission spectroscopy to relate compound stoichiometry to band structure and characterize band alignment to silicon. The direct silicon/metal oxide interface is further analyzed by quasi-steady state photoconductance decay method to assess the quality of surface

  15. 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/.

  16. 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.}

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

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

    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 ...

  18. 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.

  19. 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.

  20. 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., 20–5000 μm) and cavity height (e.g., 200–1000 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.

  1. 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.

  2. Process and apparatus for casting multiple silicon wafer articles

    DOE Patents [OSTI]

    Nanis, Leonard

    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. Unique Quantum Effect Found in Silicon Nanocrystals - News Releases...

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

    MEG provides a way to convert some of this energy lost as heat into additional electricity. The silicon nanocrystals produced by Innovalight, Inc., a thin-film solar cell developer ...

  4. 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

  5. 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 ...

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

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

    a novel path to producing solar cells with higher conversion efficiencies at lower cost. ... Often referred to as the "Oscars of Innovation," the awards are given to the top 100 ...

  7. 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 ...

  8. Control of back surface reflectance from aluminum alloyed contacts on silicon solar cells

    SciTech Connect (OSTI)

    Cudzinovic, M.; Sopori, B.

    1996-05-01

    A process for forming highly reflective aluminum back contacts with low contact resistance to silicon solar cells is described. By controlling the process conditions, it is possible to vary the silicon/aluminum interface from a specular to a diffuse reflector while maintaining a high interface reflectance. The specular interface is found to be a uniform silicon/aluminum alloy layer a few angstroms thick that has epitaxially regrown on the silicon. The diffuse interface consists of randomly distributed (111) pyramids produced by crystallographic out-diffusion of the bulk silicon. The light trapping ability of the diffuse contact is found to be close to the theoretical limit. Both types of contacts are found to have specific contact resistivities of 10{sup {minus}5} {Omega}-cm{sup 2}. The process for forming the contacts involves illuminating the devices with tungsten halogen lamps. The process is rapid (under 100 s) and low temperature (peak temperature < 580{degrees}C), making it favorable for commercial solar cell fabrication.

  9. 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.

  10. 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 μm, 0.75 μm, and 0.5 μm). 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 μm dielectric layer between the Cu and the molten Si layer, a favorable condition for monolithic 3D integration.