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DOE OSTI · 1877026

Low-temperature and effective ex situ group V doping for efficient polycrystalline CdSeTe solar cells

Li, Deng-Bing·Yao, Canglang·Vijayaraghavan, S. N.·Awni, Rasha A.·Subedi, Kamala K.·Ellingson, Randy J.·Li, Lin·Yan, Yanfa·Yan, Feng
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Abstract

CdTe solar cell technology is one of the lowest-cost methods of generating electricity in the solar industry, benefiting from fast CdTe absorber deposition, CdCl 2 treatment and Cu doping. However, Cu doping has low photovoltage and issues with instability. Doping group V elements into CdTe is therefore a promising route to address these challenges. Although high-temperature in situ group V doped CdSeTe devices have demonstrated efficiencies exceeding 20%, they face obstacles including post-deposition doping activation processes, short carrier lifetimes and low activation ratios. Here, we demonstrate low-temperature and effective ex situ group V doping for CdSeTe solar cells using group V chlorides. For AsCl 3 doped CdSeTe solar cells, the dopant activation ratio can be 5.88%, hole densities reach >2 × 10 15 cm -3 and carrier lifetime is longer than 20 ns. Thus, ex situ As doped CdSeTe solar cells show open-circuit voltages ~863 mV, compared to the highest open-circuit voltage of 852 mV for Cu doped CdSeTe solar cells.

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14 SOLAR ENERGYCdTe solar cellsEfficiencyGroup V Chlorides dopingLow-temperaturePolycrystalline CdSeTe Solar Cellsexsitu diffusion dopinggroup V doping

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Li, Deng-Bing, Yao, Canglang, Vijayaraghavan, S. N., Awni, Rasha A., Subedi, Kamala K., Ellingson, Randy J., Li, Lin, Yan, Yanfa, Yan, Feng. 2021-06-24. Low-temperature and effective ex situ group V doping for efficient polycrystalline CdSeTe solar cells. https://doi.org/10.1038/s41560-021-00848-z

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