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Title: Dramatic Recrystallization During CdCl2 Treatment of Evaporated CdTe Thin Filmsa
In this work, we report the different effects of CdCl 2 treatment on CdTe films deposited by thermal evaporation onto CdS and MgZnO (MZO) buffer layers. The main finding, which is relevant for understanding recent advances in CdTe device efficiency, is that few-μm thick CdTe films deposited on MZO can be induced to completely recrystallize forming a film consisting of grains that span the film thickness and are up to 30 μm laterally. On CdS buffer layers, the changes in microstructure with Cl treatment are much less pronounced and the final microstructure is less ideal for thin film photovoltaics. We propose a thermodynamic framework for understanding the microstructural changes during CdCl 2 treatment which can assist in understanding the wide range of behaviors observed across the many CdTe thin film solar cell fabrication procedures.  more » « less
Award ID(s):
1711885
PAR ID:
10121610
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC)
Page Range / eLocation ID:
176-179
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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