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Development of copper-free ZnTe buffer layers for CdTe-based solar cells is an important avenue for improving stability. Group V elements offer a path towards that goal. This work explores two group V elements, phosphorous and antimony, as candidates for making copper-free p-type ZnTe buffer layer using thermal evaporation. It is found that incorporation of both elements into ZnTe film can easily be done. In addition, as deposited ZnTe films are Te-rich and Cd1-xZnxTe alloys form upon co-evaporation of ZnTe and Cd3P2 , improving crystallinity and stoichiometry of the film. Activation of P poses a challenge, while ZnTe films with Sb produced good sheet resistance values.
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Effect of Process Temperature and Copper Doping on the Performance of ZnTe:Cu Back Contacts in CdTe Photovoltaics
CdTe photovoltaic devices with a ZnTe back contact have the potential to improve device performance and stability. After performing a sweep of ZnTe deposition and annealing temperatures, device performances were evaluated. Copper doping was performed after the ZnTe depositions by sublimating CuCl. Initial results indicate that ZnTe deposited and annealed for 20 minutes at 250°C improved device performance in terms of fill factor, J SC , and V OC as compared to other deposition temperatures. Copper doping also impacted device performance and a longer copper treatment on ZnTe led to a 17.6% device.
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- Award ID(s):
- 1821526
- PAR ID:
- 10173543
- Date Published:
- Journal Name:
- 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC)
- Page Range / eLocation ID:
- 0189 to 0192
- 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/PVSC40753.2019.8981395
