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Title: Sputtered Aluminum Oxide and p + Amorphous Silicon Back-Contact for Improved Hole Extraction in Polycrystalline CdSe x Te 1-x and CdTe Photovoltaics
A thin layer of Al 2 O 3 at the back of CdSe x T e1-x /CdTe devices is shown to passivate the back interface and drastically improve surface recombination lifetimes and photoluminescent response. Despite this, such devices do not show an improvement in open-circuit voltage (V OC. ) Adding a p + amorphous silicon layer behind the Al 2 O 3 bends the conduction band upward, reducing the barrier to hole extraction and improving collection. Further optimization of the Al 2 O 3 , amorphous silicon (a-Si), and indium-doped tin oxide (ITO) layers, as well as their interaction with the CdCl 2 passivation process, are necessary to translate these electro-optical improvements into gains in voltage.  more » « less
Award ID(s):
1821526
NSF-PAR ID:
10173541
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
2019 IEEE 46th Photovoltaic Specialists Conference (PVSC)
Page Range / eLocation ID:
3018 to 3023
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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