Rapid progress has been achieved in thin film CdTe solar cells, reaching a power conversion efficiency of 22.1 %. Researchers demonstrated a short-circuit current density (Jsc) of ≈ 31 mA/cm2 and a fill factor (FF) of ≈ 79 %, close to the theoretically calculated maximum values. However, the open-circuit voltage (Voc) remains below 0.9 V, much lower than the estimated Voc of 1.2 V. One strategy to improve the Voc is to implement a passivated back-contact on CdTe that can reduce the recombination by repelling minority carriers at the surface (i.e., electrons in CdTe). An aluminum oxide thin film (Al2O3) is an attractive candidate owing to its innate fixed negative charges (1012 ~ 1013 cm-2). Here, we use a patterned Al2O3 layer on CdTe to produce PERC-like CdTe solar cells (CdTe PERC).
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Doping CdSe x Te 1-x /CdTe Graded Absorber Films with Arsenic for Thin-Film Photovoltaics
CdTe thin-film photovoltaics have demonstrated some of the lowest costs of electricity generation owing to its low material cost and ease of manufacturing. However, the full potential of polycrystalline CdTe photovoltaics can only be realized if the open-circuit voltage can be increased beyond 1 V Open-circuit voltage ~850-900 mV has been consistently observed for state-of-the-art polycrystalline CdTe solar cells. Open-circuit voltage of over 1V has been demonstrated for single crystal CdTe devices by doping with Group V elements. Therefore, this study is aimed at understanding behavior of polycrystalline CdTe devices with arsenic doping, its activation and process and performance optimization in order to overcome current voltage limitations in CdTe solar cells.
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- Award ID(s):
- 1821526
- PAR ID:
- 10173542
- Date Published:
- Journal Name:
- 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC)
- Page Range / eLocation ID:
- 28 to 31
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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