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Title: Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221

Abstract

The unique properties of the semiconductor ZnTeO were explored and developed to make multiband solar cells. Like a multijunction cell, multiband solar cells use different energy gaps to convert the majority of the solar spectrum to electrical current while minimizing losses due to heating. Unlike a multijunction cell, this is accomplished within a single material in a multiband cell. ZnTe{sub 1-x}O{sub x} films with x up to 2% were synthesized and shown to have the requisite unique band structure (2 conduction bands) for multiband function. Prototype solar cells based on an n-type ZnTe{sub 1-x}O{sub x} multiband top layer and a p-type ZnTe substrate were fabricated. Contacts to the cell and the series resistance of the substrate were identified as challenges for good electrical performance. Both photovoltage and small photocurrents were demonstrated under AMO illumination. A second semiconductor system, GaN{sub x}As{sub 1-y-x}P{sub y}, was shown to have multiband function. This alloy system may have the greatest potential to realize the promise of high efficiency multiband solar cells because of the relatively advanced technology base that exists for the manufacturing of III-V-alloy-based IC and opto-electronic devices (including multijunction solar cells).

Authors:
; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director, Office of Science
OSTI Identifier:
919750
Report Number(s):
LBNL-59768
R&D Project: M50020; TRN: US200825%%388
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; ALLOY SYSTEMS; EFFICIENCY; ENERGY GAP; HEATING; ILLUMINANCE; MANUFACTURING; PERFORMANCE; PHOTOCURRENTS; SOLAR CELLS; SUBSTRATES; High efficiency solar cells

Citation Formats

Ager III, Joel W., Walukiewicz, W., and Yu, Kin Man. Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221. United States: N. p., 2006. Web. doi:10.2172/919750.
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Ager III, Joel W., Walukiewicz, W., & Yu, Kin Man. Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221. United States. doi:10.2172/919750.
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Ager III, Joel W., Walukiewicz, W., and Yu, Kin Man. Wed . "Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221". United States. doi:10.2172/919750. https://www.osti.gov/servlets/purl/919750.
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@article{osti_919750,
title = {Ultrahigh Efficiency Multiband Solar Cells Final Report forDirector's Innovation Initiative Project DII-2005-1221},
author = {Ager III, Joel W. and Walukiewicz, W. and Yu, Kin Man},
abstractNote = {The unique properties of the semiconductor ZnTeO were explored and developed to make multiband solar cells. Like a multijunction cell, multiband solar cells use different energy gaps to convert the majority of the solar spectrum to electrical current while minimizing losses due to heating. Unlike a multijunction cell, this is accomplished within a single material in a multiband cell. ZnTe{sub 1-x}O{sub x} films with x up to 2% were synthesized and shown to have the requisite unique band structure (2 conduction bands) for multiband function. Prototype solar cells based on an n-type ZnTe{sub 1-x}O{sub x} multiband top layer and a p-type ZnTe substrate were fabricated. Contacts to the cell and the series resistance of the substrate were identified as challenges for good electrical performance. Both photovoltage and small photocurrents were demonstrated under AMO illumination. A second semiconductor system, GaN{sub x}As{sub 1-y-x}P{sub y}, was shown to have multiband function. This alloy system may have the greatest potential to realize the promise of high efficiency multiband solar cells because of the relatively advanced technology base that exists for the manufacturing of III-V-alloy-based IC and opto-electronic devices (including multijunction solar cells).},
doi = {10.2172/919750},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Mar 29 00:00:00 EST 2006},
month = {Wed Mar 29 00:00:00 EST 2006}
}
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Technical Report:
View Technical Report (2.18 MB)
DOI:  10.2172/919750
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