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Title: Microchannel contacting of crystalline silicon solar cells

Abstract

There is tremendous interest in reducing losses caused by the metal contacts in silicon photovoltaics, particularly the optical and resistive losses of the front metal grid. One commonly sought-after goal is the creation of high aspect-ratio metal fingers which provide an optically narrow and low resistance pathway to the external circuit. Currently, the most widely used metal contact deposition techniques are limited to widths and aspect-ratios of ~40 μm and ~0.5, respectively. In this study, we introduce the use of a micropatterned polydimethylsiloxane encapsulation layer to form narrow (~20 μm) microchannels, with aspect-ratios up to 8, on the surface of solar cells. We demonstrate that low temperature metal pastes, electroless plating and atomic layer deposition can all be used within the microchannels. Further, we fabricate proof-of-concept structures including simple planar silicon heterojunction and homojunction solar cells. While preliminary in both design and efficiency, these results demonstrate the potential of this approach and its compatibility with current solar cell architectures.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [2];  [2];  [3];  [3];  [2];  [1]
  1. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. The Australian National Univ., Canberra, ACT (Australia)
  3. Ecole Polytechnique Federale de Lausanne (EPFL), Neuchatel (Switzerland)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1417622
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE

Citation Formats

Bullock, James, Ota, Hiroki, Wang, Hanchen, Xu, Zhaoran, Hettick, Mark, Yan, Di, Samundsett, Christian, Wan, Yimao, Essig, Stephanie, Morales-Masis, Monica, Cuevas, Andres, and Javey, Ali. Microchannel contacting of crystalline silicon solar cells. United States: N. p., 2017. Web. https://doi.org/10.1038/s41598-017-08913-y.
Bullock, James, Ota, Hiroki, Wang, Hanchen, Xu, Zhaoran, Hettick, Mark, Yan, Di, Samundsett, Christian, Wan, Yimao, Essig, Stephanie, Morales-Masis, Monica, Cuevas, Andres, & Javey, Ali. Microchannel contacting of crystalline silicon solar cells. United States. https://doi.org/10.1038/s41598-017-08913-y
Bullock, James, Ota, Hiroki, Wang, Hanchen, Xu, Zhaoran, Hettick, Mark, Yan, Di, Samundsett, Christian, Wan, Yimao, Essig, Stephanie, Morales-Masis, Monica, Cuevas, Andres, and Javey, Ali. Tue . "Microchannel contacting of crystalline silicon solar cells". United States. https://doi.org/10.1038/s41598-017-08913-y. https://www.osti.gov/servlets/purl/1417622.
@article{osti_1417622,
title = {Microchannel contacting of crystalline silicon solar cells},
author = {Bullock, James and Ota, Hiroki and Wang, Hanchen and Xu, Zhaoran and Hettick, Mark and Yan, Di and Samundsett, Christian and Wan, Yimao and Essig, Stephanie and Morales-Masis, Monica and Cuevas, Andres and Javey, Ali},
abstractNote = {There is tremendous interest in reducing losses caused by the metal contacts in silicon photovoltaics, particularly the optical and resistive losses of the front metal grid. One commonly sought-after goal is the creation of high aspect-ratio metal fingers which provide an optically narrow and low resistance pathway to the external circuit. Currently, the most widely used metal contact deposition techniques are limited to widths and aspect-ratios of ~40 μm and ~0.5, respectively. In this study, we introduce the use of a micropatterned polydimethylsiloxane encapsulation layer to form narrow (~20 μm) microchannels, with aspect-ratios up to 8, on the surface of solar cells. We demonstrate that low temperature metal pastes, electroless plating and atomic layer deposition can all be used within the microchannels. Further, we fabricate proof-of-concept structures including simple planar silicon heterojunction and homojunction solar cells. While preliminary in both design and efficiency, these results demonstrate the potential of this approach and its compatibility with current solar cell architectures.},
doi = {10.1038/s41598-017-08913-y},
journal = {Scientific Reports},
number = 1,
volume = 7,
place = {United States},
year = {2017},
month = {8}
}

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Cited by: 4 works
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Figures / Tables:

Figure 1 Figure 1: Microchannel contacted solar cell concept. (a) Basic fabrication procedure for microchannel contacted solar cells, (b) Comparison of aspect-ratio for conventional and microchannel based solar cell contacts, the individual figures approximately reflect their size relative to each other. Cross sectional SEM images of (c) high aspect-ratio microchannel (90° crossmore » section); (d) triangular microchannel (90° cross section); (e) textured surface bonding (45° cross section); and (f) magnified bonding to textured surface (45° cross section).« less

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    journal, March 2019


      Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.