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DOE OSTI · 1878343

Hybrid Functional Calculations for Antimony Doping in CdTe

Chatratin, Intuon·Mukherjee, Shagorika·Janotti, Anderson
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Abstract

CdTe-based solar cells are leading thin-film photovoltaic technology, with efficiencies over 22%, but still much lower than the theoretical maximum of 29%. Further improvements will rely on increasing the open-circuit voltage Voc, which, in turn, depends on carrier density and lifetime. Using hybrid density functional calculations, we investigate Sb doping of CdTe, focusing on its limitation as shallow acceptor and the formation of compensating AX center. Paying special attention to supercell size and effects of spin-orbit coupling, we predict an ionization energy of 116 meV in the dilute limit, much closer to recent experimental value of 103 meV from temperature-dependent Hall measurements in bulk single crystals, and in contrast to much larger values from previous calculations. We also find that the Sb-related AX centers are not major compensation centers in Sb-doped CdTe.

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14 SOLAR ENERGYCdTe, solar cells, defects

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Chatratin, Intuon, Mukherjee, Shagorika, Janotti, Anderson. 2022-06-06. Hybrid Functional Calculations for Antimony Doping in CdTe. https://doi.org/10.1109/pvsc48317.2022.9938763

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