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Cadmium telluride and silicon are among the widely used absorber materials in photovoltaic industry. A tandem solar cell of these two can absorb significant portion of solar spectrum to yield high efficiency due to the added voltage of the two solar cells. On basis of low-cost production, a CdTe/Si cell has the potential to produce low-cost and high efficiency tandem PV. The CdTe top cell in a substrate configuration is essential to achieve a tandem between CdTe and Si. A functional CdS/CdTe solar cell in the substrate configuration was fabricated on a Si wafer. Current -Voltage measurements show a diode-like curve with lower J-V parameters compared to standard CdS/CdTe cells. SCAPS simulations were performed to identify possible reasons for poor performance and help improve the device performance.
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Controlling Silicon Bottom Cell Lifetime Variance in II-VI/Si Tandems
An intricate look is taken at the methods used to account for variance in minority-carrier lifetime in the silicon bottom cell of II-VI/Si tandem solar cells. A discussion on the modeling is provided. Lateral wafer variance is determined to be much less than wafer-to-wafer variance. Size testing indicates a minimum size of 4 × 4 cm is necessary for accurate results. The cleaning procedure and photoluminescence testing is described. Despite a small sample size, Si samples with CdTe deposition and CdCl2 treatment maintain over 1 ms lifetimes, enabling the Si bottom cell in II-VI/Si tandem cells to reach state-of-the-art performance.
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- Award ID(s):
- 1665299
- PAR ID:
- 10194058
- Date Published:
- Journal Name:
- 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC)
- Page Range / eLocation ID:
- 2188 to 2191
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/PVSC40753.2019.8980707
