Evidence of Buried Junctions in CdSeTe Absorbers

Jones, Sean M.; Moseley, John; Gorman, Brian P.; Al-Jassim, Mowafak; Ablekim, Tursun; Guthrey, Harvey (ORCID:0000000315743379)

doi:10.1109/pvsc45281.2020.9300427

DOE OSTI · 1669554

Evidence of Buried Junctions in CdSeTe Absorbers

Jones, Sean M.·Moseley, John·Gorman, Brian P.·Al-Jassim, Mowafak·Ablekim, Tursun·Guthrey, Harvey (ORCID:0000000315743379)

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Abstract

The introduction of selenium band gap gradients has been shown to be a promising path for improving CdTe devices. Controlling maximum selenium concentration during deposition should allow for better device performance. In this work cross-section electron beam induced current (EBIC) maps were measured for CdSeTe/CdTe devices with as-grown selenium concentration between 0 and 20 percent. Measured EBIC profiles show high collection in the middle of the absorber layer, which differs from past EBIC studies of CdSe/CdTe devices. Increasing as-deposited selenium concentrations resulted in increased collection at this mid-absorber location. Combined with a 2-dimensional numerical model, these results suggest a buried homo-junction in the absorber layer of the device. This buried junction may be associated with a number of composition dependent parameters including electron affinity and p-dopability. Understanding this collection profile and its implications for device performance may be key in optimizing CdSeTe/CdTe devices.

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Jones, Sean M., Moseley, John, Gorman, Brian P., Al-Jassim, Mowafak, Ablekim, Tursun, Guthrey, Harvey (ORCID:0000000315743379). 2020-08-24. Evidence of Buried Junctions in CdSeTe Absorbers. https://doi.org/10.1109/pvsc45281.2020.9300427

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