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DOE OSTI · 2204848

Quantifying carrier dynamics and PL characterization of antimony-doped CdTe and CdSeTe

Manoukian, Gregory·Du, Bin·Fai, Calvin·Hages, Charles·Shafarman, William·Baxter, Jason
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Abstract

Our team has achieved ~20% doping activation of CdSeTe with antimony (Sb), whose shallow acceptor level makes it a viable alternative to As.1,2 Arsenic (As)-doped graded CdSeTe photovoltaics have achieved record efficiencies of 22.3%. Remaining challenges include doping activation of only ~2% in polycrystalline films and radiative voltage losses of ~100 mV. Here we use (transient) terahertz and photoluminescence spectroscopy of CdTe:Sb and CdSeTe:Sb to show sufficiently long bulk lifetimes to enable high-efficiency devices. Early results also indicate dominant bandgap emission in CdSeTe:Sb and a lack of potential fluctuations with Sb-doping that have proven detrimental for As-doped films. While more work is needed, these results show significant promise for Sb doping.

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Manoukian, Gregory, Du, Bin, Fai, Calvin, Hages, Charles, Shafarman, William, Baxter, Jason. 2023-10-25. Quantifying carrier dynamics and PL characterization of antimony-doped CdTe and CdSeTe. https://doi.org/10.2172/2204848

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