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Title: Local Photovoltaic Measurements of CdTe Solar Cells Using Microscale Point Back-Contacts
Cadmium telluride (CdTe) thin-film semiconductors exhibit many desirable properties for low-cost and high-efficiency photovoltaic (PV) technology, including inherent robustness of inorganic absorber, a direct bandgap that allows full absorption of the solar spectrum with thicknesses of only few microns, and inexpensive and high-throughput manufacturing processes. At the best efficiency of 22 %, the power conversion efficiency of CdTe PVs is still well below the maximum theoretical limit (approximately 30 %). It has been suggested that the inferior efficiency is mainly attributed to the inherent polycrystalline nature of CdTe absorber (e.g., grains, grain boundaries). Understanding local photocarrier dynamics is vital to overcoming roadblocks toward higher efficiency CdTe PVs. However, conventional cell-level PV measurements often limit the microstructural analysis. In this work, we present a local PV characterization technique using point back-contacts. The thin-film CdTe solar cells used in this work were prepared by CSS (close-spaced sublimation) on a stack of n-type window layer (e.g., CdS) / transparent conductive layer (TCO; e.g., SnO2) / glass substrate.  more » « less
Award ID(s):
1711885
PAR ID:
10310242
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
electronic materials conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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