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Title: Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe

Abstract

Cryogenic focused ion beam (Cryo-FIB) milling at near-grazing angles is employed to fabricate cross-sections on thin Cu(In,Ga)Se2 with >8x expansion in thickness. Kelvin probe force microscopy (KPFM) on sloped cross sections showed reduction in grain boundaries potential deeper into the film. Cryo Fib-KPFM enabled the first determination of the electronic structure of the Mo/CIGSe back contact, where a sub 100 nm thick MoSey assists hole extraction due to 45 meV higher work function. This demonstrates that CryoFIB-KPFM combination can reveal new targets of opportunity for improvement in thin-films photovoltaics such as high-work-function contacts to facilitate hole extraction through the back interface of CIGS.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1260136
Report Number(s):
NREL/JA-5K00-66733
Journal ID: ISSN 1944-8244
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: ACS Applied Materials and Interfaces; Journal Volume: 8; Journal Issue: 24
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; back contacts; CIGSe; Cryo-FIB; KPFM; thin-film photovoltaics

Citation Formats

Sardashti, Kasra, Haight, Richard, Anderson, Ryan, Contreras, Miguel, Fruhberger, Bernd, and Kummel, Andrew C. Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe. United States: N. p., 2016. Web. doi:10.1021/acsami.6b04214.
Sardashti, Kasra, Haight, Richard, Anderson, Ryan, Contreras, Miguel, Fruhberger, Bernd, & Kummel, Andrew C. Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe. United States. doi:10.1021/acsami.6b04214.
Sardashti, Kasra, Haight, Richard, Anderson, Ryan, Contreras, Miguel, Fruhberger, Bernd, and Kummel, Andrew C. 2016. "Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe". United States. doi:10.1021/acsami.6b04214.
@article{osti_1260136,
title = {Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe},
author = {Sardashti, Kasra and Haight, Richard and Anderson, Ryan and Contreras, Miguel and Fruhberger, Bernd and Kummel, Andrew C.},
abstractNote = {Cryogenic focused ion beam (Cryo-FIB) milling at near-grazing angles is employed to fabricate cross-sections on thin Cu(In,Ga)Se2 with >8x expansion in thickness. Kelvin probe force microscopy (KPFM) on sloped cross sections showed reduction in grain boundaries potential deeper into the film. Cryo Fib-KPFM enabled the first determination of the electronic structure of the Mo/CIGSe back contact, where a sub 100 nm thick MoSey assists hole extraction due to 45 meV higher work function. This demonstrates that CryoFIB-KPFM combination can reveal new targets of opportunity for improvement in thin-films photovoltaics such as high-work-function contacts to facilitate hole extraction through the back interface of CIGS.},
doi = {10.1021/acsami.6b04214},
journal = {ACS Applied Materials and Interfaces},
number = 24,
volume = 8,
place = {United States},
year = 2016,
month = 6
}
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