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Title: The Effect of Crystallographic Orientation and Nanoscale Surface Morphology on Poly-Si/SiO x Contacts for Silicon Solar Cells

Abstract

High-efficiency crystalline silicon (Si) solar cells require textured surfaces for efficient light trapping. However, passivation of a textured surface to reduce carrier recombination is difficult. Here, we related the electrical properties of cells fabricated on a KOH-etched, random pyramidal textured Si surface to nanostructure of the passivated contact and the textured surface morphology. The effects of both microscopic pyramidal morphology and nanoscale surface roughness on passivated contacts consisting of a polycrystalline Si (poly-Si) deposited on top of an ultrathin, 1.5-2.2 nm, SiOx layer is investigated. Using atomic force microscopy we show a pyramid face, which is predominantly a Si(111) plane to be significantly rougher than a polished Si(111) surface. This roughness results in a nonuniform SiOx layer as determined by transmission electron microscopy (TEM) of a poly-Si/SiOx contact. Our device measurements also show an overall more resistive, and hence thicker SiOx layer over the pyramidal surface as compared to a polished Si(111) surface, which we relate to increased roughness. Using electron-beam-induced current measurements of poly-Si/SiOx contacts we further show that the SiOx layer near the pyramid valleys is preferentially more conducting, and hence likely thinner than over pyramid tips, edges and faces. Hence, both the microscopic pyramidal morphology and nanoscalemore » roughness lead to nonuniform SiOx layer, thus leading to poor poly-Si/SiOx contact passivation. Finally, we report >21% efficient and =80% fill factor front/back poly-Si/SiOx solar cells on both single-side and double-side textured wafers without the use of transparent conductive oxide layers and show that the poorer contact passivation on a textured surface is limited to boron-doped poly-Si/SiOx contacts.« less

Authors:
 [1];  [2]; ORCiD logo [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [3]
+ Show Author Affiliations
  1. Colorado School of Mines, Golden, CO (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Colorado School of Mines, Golden, CO (United States)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
OSTI Identifier:
1571392
Report Number(s):
NREL/JA-5900-75083
Journal ID: ISSN 1944-8244
Grant/Contract Number:  
AC36-08GO28308
Resource Type:
Accepted Manuscript
Journal Name:
ACS Applied Materials and Interfaces
Additional Journal Information:
Journal Volume: 11; Journal Issue: 45; Journal ID: ISSN 1944-8244
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; silicon solar cell; passivated contact; silicon oxide; tunneling; surface orientation; electron beam induced current; atomic force microscopy

Citation Formats

Kale, Abhijit, Nemeth, William M., Guthrey, Harvey L., Nanayakkara, Sanjini U., LaSalvia, Vincenzo A., Theingi, San, Findley, Dawn, Page, Matthew, Al-Jassim, Mowafak M., Young, David L., Stradins, Pauls, and Agarwal, Sumit. The Effect of Crystallographic Orientation and Nanoscale Surface Morphology on Poly-Si/SiO x Contacts for Silicon Solar Cells. United States: N. p., 2019. Web. doi:10.1021/acsami.9b11889.
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Kale, Abhijit, Nemeth, William M., Guthrey, Harvey L., Nanayakkara, Sanjini U., LaSalvia, Vincenzo A., Theingi, San, Findley, Dawn, Page, Matthew, Al-Jassim, Mowafak M., Young, David L., Stradins, Pauls, & Agarwal, Sumit. The Effect of Crystallographic Orientation and Nanoscale Surface Morphology on Poly-Si/SiO x Contacts for Silicon Solar Cells. United States. https://doi.org/10.1021/acsami.9b11889
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Kale, Abhijit, Nemeth, William M., Guthrey, Harvey L., Nanayakkara, Sanjini U., LaSalvia, Vincenzo A., Theingi, San, Findley, Dawn, Page, Matthew, Al-Jassim, Mowafak M., Young, David L., Stradins, Pauls, and Agarwal, Sumit. Tue . "The Effect of Crystallographic Orientation and Nanoscale Surface Morphology on Poly-Si/SiO x Contacts for Silicon Solar Cells". United States. https://doi.org/10.1021/acsami.9b11889. https://www.osti.gov/servlets/purl/1571392.
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@article{osti_1571392,
title = {The Effect of Crystallographic Orientation and Nanoscale Surface Morphology on Poly-Si/SiO x Contacts for Silicon Solar Cells},
author = {Kale, Abhijit and Nemeth, William M. and Guthrey, Harvey L. and Nanayakkara, Sanjini U. and LaSalvia, Vincenzo A. and Theingi, San and Findley, Dawn and Page, Matthew and Al-Jassim, Mowafak M. and Young, David L. and Stradins, Pauls and Agarwal, Sumit},
abstractNote = {High-efficiency crystalline silicon (Si) solar cells require textured surfaces for efficient light trapping. However, passivation of a textured surface to reduce carrier recombination is difficult. Here, we related the electrical properties of cells fabricated on a KOH-etched, random pyramidal textured Si surface to nanostructure of the passivated contact and the textured surface morphology. The effects of both microscopic pyramidal morphology and nanoscale surface roughness on passivated contacts consisting of a polycrystalline Si (poly-Si) deposited on top of an ultrathin, 1.5-2.2 nm, SiOx layer is investigated. Using atomic force microscopy we show a pyramid face, which is predominantly a Si(111) plane to be significantly rougher than a polished Si(111) surface. This roughness results in a nonuniform SiOx layer as determined by transmission electron microscopy (TEM) of a poly-Si/SiOx contact. Our device measurements also show an overall more resistive, and hence thicker SiOx layer over the pyramidal surface as compared to a polished Si(111) surface, which we relate to increased roughness. Using electron-beam-induced current measurements of poly-Si/SiOx contacts we further show that the SiOx layer near the pyramid valleys is preferentially more conducting, and hence likely thinner than over pyramid tips, edges and faces. Hence, both the microscopic pyramidal morphology and nanoscale roughness lead to nonuniform SiOx layer, thus leading to poor poly-Si/SiOx contact passivation. Finally, we report >21% efficient and =80% fill factor front/back poly-Si/SiOx solar cells on both single-side and double-side textured wafers without the use of transparent conductive oxide layers and show that the poorer contact passivation on a textured surface is limited to boron-doped poly-Si/SiOx contacts.},
doi = {10.1021/acsami.9b11889},
journal = {ACS Applied Materials and Interfaces},
number = 45,
volume = 11,
place = {United States},
year = {Tue Oct 15 00:00:00 EDT 2019},
month = {Tue Oct 15 00:00:00 EDT 2019}
}
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Journal Article:
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Publisher's Version of Record
https://doi.org/10.1021/acsami.9b11889
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Cited by: 16 works
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Figures / Tables:

Figure 1 Figure 1: (a) Schematic of front/back poly-Si/SiOx contact cells on SST and DST n-Cz Si wafers. (b) Cross section SEM image of the front-side of the Al/n + poly-Si/SiOx/n-Si contact stack on a textured Si surface. (c) Current-voltage measurements of the cells shown in “a”. The table in the insetmore » shows their cell parameters.« less
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Works referenced in this record:

Solar cell efficiency tables (version 51)
journal, December 2017

  • Green, Martin A.; Hishikawa, Yoshihiro; Dunlop, Ewan D.
  • Progress in Photovoltaics: Research and Applications, Vol. 26, Issue 1
  • DOI: 10.1002/pip.2978

n-Type Si solar cells with passivating electron contact: Identifying sources for efficiency limitations by wafer thickness and resistivity variation
journal, December 2017

Silicon heterojunction solar cell with interdigitated back contacts for a photoconversion efficiency over 26%
journal, March 2017

Light trapping properties of pyramidally textured surfaces
journal, July 1987

  • Campbell, Patrick; Green, Martin A.
  • Journal of Applied Physics, Vol. 62, Issue 1, p. 243-249
  • DOI: 10.1063/1.339189

Minimizing lifetime degradation associated with thermal oxidation of upright randomly textured silicon surfaces
journal, January 2006

Effect of texturing and surface preparation on lifetime and cell performance in heterojunction silicon solar cells
journal, November 2008

Tunnel oxide passivated carrier-selective contacts based on ultra-thin SiO 2 layers
journal, November 2015

High-eficiency silicon solar cells: Si/SiO2, interface parameters and their impact on device performance
journal, October 1994

  • Aberle, A. G.; Glunz, S. W.; Stephens, A. W.
  • Progress in Photovoltaics: Research and Applications, Vol. 2, Issue 4
  • DOI: 10.1002/pip.4670020402

Surface passivation of crystalline silicon solar cells: a review
journal, September 2000

Dielectric surface passivation for silicon solar cells: A review
journal, June 2017

  • Bonilla, Ruy S.; Hoex, Bram; Hamer, Phillip
  • physica status solidi (a), Vol. 214, Issue 7
  • DOI: 10.1002/pssa.201700293

A 720 mV open circuit voltage SiO x : c ‐Si:SiO x double heterostructure solar cell
journal, December 1985

  • Yablonovitch, E.; Gmitter, T.; Swanson, R. M.
  • Applied Physics Letters, Vol. 47, Issue 11
  • DOI: 10.1063/1.96331

Dependence of Interface State Density on Silicon Thermal Oxidation Process Variables
journal, January 1979

  • Razouk, Reda R.; Deal, Bruce E.
  • Journal of The Electrochemical Society, Vol. 126, Issue 9, p. 1573-1581
  • DOI: 10.1149/1.2129333

The application of poly-Si/SiOx contacts as passivated top/rear contacts in Si solar cells
journal, January 2017

Phosphorous-Doped Silicon Carbide as Front-Side Full-Area Passivating Contact for Double-Side Contacted c-Si Solar Cells
journal, March 2019

Bias temperature instability in scaled p/sup +/ polysilicon gate p-MOSFET's
journal, May 1999

  • Yamamoto, T.; Uwasawa, K.; Mogami, T.
  • IEEE Transactions on Electron Devices, Vol. 46, Issue 5
  • DOI: 10.1109/16.760398

Discontinuity of B‐diffusion profiles at the interface of polycrystalline Si and single crystal Si
journal, April 1993

  • Batra, S.; Manning, M.; Dennison, C.
  • Journal of Applied Physics, Vol. 73, Issue 8
  • DOI: 10.1063/1.352886

Contacting boron emitters on n-type silicon solar cells with aluminium-free silver screen-printing pastes
journal, February 2016

  • Fritz, Susanne; Engelhardt, Josh; Ebert, Stefanie
  • physica status solidi (RRL) - Rapid Research Letters, Vol. 10, Issue 4
  • DOI: 10.1002/pssr.201510443

Polycrystalline silicon passivated tunneling contacts for high efficiency silicon solar cells
journal, March 2016

  • Nemeth, Bill; Young, David L.; Page, Matthew R.
  • Journal of Materials Research, Vol. 31, Issue 6, p. 671-681
  • DOI: 10.1557/jmr.2016.77

Effect of silicon oxide thickness on polysilicon based passivated contacts for high-efficiency crystalline silicon solar cells
journal, October 2018

Thermal oxidation of silicon in various oxygen partial pressures diluted by nitrogen
journal, July 1977

  • Kamigaki, Y.; Itoh, Y.
  • Journal of Applied Physics, Vol. 48, Issue 7
  • DOI: 10.1063/1.324099

Thick-film metallization for solar cell applications
journal, May 1984

  • Che, G. C.; Mertens, R. P.; Van Overstraeten, R.
  • IEEE Transactions on Electron Devices, Vol. 31, Issue 5
  • DOI: 10.1109/t-ed.1984.21575

Numerical Simulations of IBC Solar Cells Based on Poly-Si Carrier-Selective Passivating Contacts
journal, March 2019

Structure and morphology of polycrystalline silicon‐single crystal silicon interfaces
journal, April 1985

  • Bravman, John C.; Patton, Gary L.; Plummer, James D.
  • Journal of Applied Physics, Vol. 57, Issue 8
  • DOI: 10.1063/1.335421

Thermal oxidation of silicon in the ultrathin regime
journal, July 1997

Effect of silicon substrate microroughness on gate oxide quality
journal, September 1996

  • Hegde, Rama I.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 14, Issue 5
  • DOI: 10.1116/1.588823

Stress effect on the kinetics of silicon thermal oxidation
journal, March 2001

  • Yen, Jui-Yuan; Hwu, Jenn-Gwo
  • Journal of Applied Physics, Vol. 89, Issue 5
  • DOI: 10.1063/1.1342801

Oxidation induced stresses and some effects on the behavior of oxide films
journal, November 1983

  • Hsueh, C. H.; Evans, A. G.
  • Journal of Applied Physics, Vol. 54, Issue 11
  • DOI: 10.1063/1.331854

Understanding the charge transport mechanisms through ultrathin SiO x layers in passivated contacts for high-efficiency silicon solar cells
journal, February 2019

  • Kale, Abhijit S.; Nemeth, William; Guthrey, Harvey
  • Applied Physics Letters, Vol. 114, Issue 8
  • DOI: 10.1063/1.5081832

Electron beam induced current studies of MS and MIS devices on CdS
journal, January 1980

  • Russell, G. J.; Robertson, M. J.; Woods, J.
  • Physica Status Solidi (a), Vol. 57, Issue 1
  • DOI: 10.1002/pssa.2210570128

Electron-beam induced current determination of shallow junction depth
journal, January 1994

  • Fitzgerald, E. A.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 12, Issue 1
  • DOI: 10.1116/1.587125

Properties of interfaces in amorphous/crystalline silicon heterojunctions
journal, March 2010

  • Olibet, Sara; Vallat-Sauvain, Evelyne; Fesquet, Luc
  • physica status solidi (a), Vol. 207, Issue 3
  • DOI: 10.1002/pssa.200982845

Stress‐related problems in silicon technology
journal, September 1991

Hydrogen passivation of poly-Si/SiO x contacts for Si solar cells using Al 2 O 3 studied with deuterium
journal, May 2018

  • Schnabel, Manuel; van de Loo, Bas W. H.; Nemeth, William
  • Applied Physics Letters, Vol. 112, Issue 20
  • DOI: 10.1063/1.5031118
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    An assessment on crystallization phenomena of Si in Al/a-Si thin films via thermal annealing and ion irradiation
    journal, January 2020

    • Maity, G.; Dubey, S.; El-Azab, Anter
    • RSC Advances, Vol. 10, Issue 8
    • DOI: 10.1039/c9ra08836a
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