High efficiency thin film CdTe and a-Si based solar cells [electronic resource]
Photovoltaics;High Efficiency;Cdte;A-Si;Thin Films;Solar Cells.
Saved in:
| Online Access: |
Online Access (via OSTI) |
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| Format: | Government Document Electronic eBook |
| Language: | English |
| Published: |
Washington, D.C. : Oak Ridge, Tenn. :
United States. Department of Energy ; distributed by the Office of Scientific and Technical Information, U.S. Department of Energy,
2000.
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| Subjects: |
| Summary: | Photovoltaics;High Efficiency;Cdte;A-Si;Thin Films;Solar Cells. |
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| Abstract: | This report describes work done by the University of Toledo during the first year of this subcontract. During this time, the CdTe group constructed a second dual magnetron sputter deposition facility; optimized reactive sputtering for ZnTe:N films to achieve 10 ohm-cm resistivity and ∼9% efficiency cells with a copper-free ZnTe:N/Ni contact; identified Cu-related photoluminescence features and studied their correlation with cell performance including their dependence on temperature and E-fields; studied band-tail absorption in CdSₓTe{sub 1−x} films at 10 K and 300 K; collaborated with the National CdTe PV Team on (1) studies of high-resistivity tin oxide (HRT) layers from ITN Energy Systems, (2) fabrication of cells on the HRT layers with 0, 300, and 800-nm CdS, and (3) preparation of ZnTe:N-based contacts on First Solar materials for stress testing; and collaborated with Brooklyn College for ellipsometry studies of CdSₓTe{sub 1−x} alloy films, and with the University of Buffalo/Brookhaven NSLS for synchrotron X-ray fluorescence studies of interdiffusion in CdS/CdTe bilayers. The a-Si group established a baseline for fabricating a-Si-based solar cells with single, tandem, and triple-junction structures; fabricated a-Si/a-SiGe/a-SiGe triple-junction solar cells with an initial efficiency of 9.7% during the second quarter, and 10.6% during the fourth quarter (after 1166 hours of light-soaking under 1-sun light intensity at 50 C, the 10.6% solar cells stabilized at about 9%); fabricated wide-bandgap a-Si top cells, the highest Voc achieved for the single-junction top cell was 1.02 V, and top cells with high FF (up to 74%) were fabricated routinely; fabricated high-quality narrow-bandgap a-SiGe solar cells with 8.3% efficiency; found that bandgap-graded buffer layers improve the performance (Voc and FF) of the narrow-bandgap a-SiGe bottom cells; and found that a small amount of oxygen partial pressure (∼2 × 10{sup −5} torr) was beneficial for growing high-quality films from ITO targets. |
| Item Description: | Published through SciTech Connect. 01/04/2000. "nrel/sr-520-27666" Compaan, A. D.; Deng, X.; Bohn, R. G. National Renewable Energy Lab., Golden, CO (US) |
| Physical Description: | vp. : digital, PDF file. |
| Type of Report and Period Covered Note: | Annual; |