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Title: High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000

Abstract

This report describes the research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Implemented a diode-array spectrograph system and used optical emission spectroscopy to help optimize the reactive sputtering of N-doped ZnTe for CdTe back-contact structures. Identified the photoluminescence signatures of various defect states in CdTe related to Cd vacancies, CuCd acceptors, Cu-VCd complexes, and donor-acceptor pairs, and related these states to instabilities in the hole concentration at room temperature. Showed that Cu is an important non-radiative center in CdS, reducing the PL efficiency. Studied band tailing in CdS weakly alloyed with CdTe and CdTe weakly alloyed with CdS. Fabricated superstrate ITO/CdS/CdTe cells on Mo substrates with efficiencies above 7.5%. Collaborated in studies of EXAFS of Cu in CdTe which indicate a Cu-Te bond length of 2.62 {angstrom} or 6.7% shorter than the CdTe, bond in agreement with calculations of Wei et al. Provided assistance to two groups on laser scribing. Comparatively studied the performance of a-SiGe solar cells and properties of a-SiGe single-layer films deposited using a wide range of H dilution, observed transition from a-SiGe to {mu}c-SiGe at high H dilution and the impact on cell performances. Comparatively studied the performance of a-SiGemore » solar cells and properties of a-SiGe single-layer films with different Ge contents, suitable for use as component cells of triple-junction devices. Fabricated a-Si-based solar cells on ultra-thin stainless-steel substrate (7.5 micron) and obtained equivalent performance and yield as on the regular SS substrates (127 microns). Comparatively studied the performance of a-Si-based solar cells on SS substrates and on SnO2-coated glass substrates. Studied the performance of p-layers deposited under various deposition conditions for n-i-p type solar cells. Performed an analysis for the component cell current-matching within a triple-junction solar cell.« less

Authors:
; ;  [1]
+ Show Author Affiliations
  1. (The University of Toledo)
Publication Date:
Research Org.:
National Renewable Energy Lab., Golden, CO (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
788762
Report Number(s):
NREL/SR-520-30739
TRN: AH200136%%220
DOE Contract Number:
AC36-99GO10337
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 29 Aug 2001
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; BOND LENGTHS; DILUTION; EFFICIENCY; EMISSION SPECTROSCOPY; PERFORMANCE; PHOTOLUMINESCENCE; SOLAR CELLS; THIN FILMS; PV; THIN-FILM SOLAR CELLS; CDTE-BASED; A-SI-BASED; LASER SCRIBING; SPUTTER PLASMAS; AMORPHOUS SILICON; TRIPLE-JUNCTION DEVICES; COMPONENT CELLS; DIODE-ARRAY SPECTROGRAPH SYSTEM; STAINLESS STEEL SUBSTRATES

Citation Formats

Compaan, A. D., Deng, X., and Bohn, R. G. High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000. United States: N. p., 2001. Web. doi:10.2172/788762.
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Compaan, A. D., Deng, X., & Bohn, R. G. High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000. United States. doi:10.2172/788762.
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Compaan, A. D., Deng, X., and Bohn, R. G. Wed . "High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000". United States. doi:10.2172/788762. https://www.osti.gov/servlets/purl/788762.
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@article{osti_788762,
title = {High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Annual Technical Report, 4 March 1999 - 3 March 2000},
author = {Compaan, A. D. and Deng, X. and Bohn, R. G.},
abstractNote = {This report describes the research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Implemented a diode-array spectrograph system and used optical emission spectroscopy to help optimize the reactive sputtering of N-doped ZnTe for CdTe back-contact structures. Identified the photoluminescence signatures of various defect states in CdTe related to Cd vacancies, CuCd acceptors, Cu-VCd complexes, and donor-acceptor pairs, and related these states to instabilities in the hole concentration at room temperature. Showed that Cu is an important non-radiative center in CdS, reducing the PL efficiency. Studied band tailing in CdS weakly alloyed with CdTe and CdTe weakly alloyed with CdS. Fabricated superstrate ITO/CdS/CdTe cells on Mo substrates with efficiencies above 7.5%. Collaborated in studies of EXAFS of Cu in CdTe which indicate a Cu-Te bond length of 2.62 {angstrom} or 6.7% shorter than the CdTe, bond in agreement with calculations of Wei et al. Provided assistance to two groups on laser scribing. Comparatively studied the performance of a-SiGe solar cells and properties of a-SiGe single-layer films deposited using a wide range of H dilution, observed transition from a-SiGe to {mu}c-SiGe at high H dilution and the impact on cell performances. Comparatively studied the performance of a-SiGe solar cells and properties of a-SiGe single-layer films with different Ge contents, suitable for use as component cells of triple-junction devices. Fabricated a-Si-based solar cells on ultra-thin stainless-steel substrate (7.5 micron) and obtained equivalent performance and yield as on the regular SS substrates (127 microns). Comparatively studied the performance of a-Si-based solar cells on SS substrates and on SnO2-coated glass substrates. Studied the performance of p-layers deposited under various deposition conditions for n-i-p type solar cells. Performed an analysis for the component cell current-matching within a triple-junction solar cell.},
doi = {10.2172/788762},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Aug 29 00:00:00 EDT 2001},
month = {Wed Aug 29 00:00:00 EDT 2001}
}
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DOI:  10.2172/788762
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  • ; ;
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  • ; ;
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