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Title: Identification of critical stacking faults in thin-film CdTe solar cells

Abstract

Cadmium telluride (CdTe) is a p-type semiconductor used in thin-film solar cells. To achieve high light-to-electricity conversion, annealing in the presence of CdCl{sub 2} is essential, but the underlying mechanism is still under debate. Recent evidence suggests that a reduction in the high density of stacking faults in the CdTe grains is a key process that occurs during the chemical treatment. A range of stacking faults, including intrinsic, extrinsic, and twin boundary, are computationally investigated to identify the extended defects that limit performance. The low-energy faults are found to be electrically benign, while a number of higher energy faults, consistent with atomic-resolution micrographs, are predicted to be hole traps with fluctuations in the local electrostatic potential. It is expected that stacking faults will also be important for other thin-film photovoltaic technologies.

Authors:
;  [1];  [2];  [3];  [1]; ;  [4]
  1. Global E3 Institute, Department of Materials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)
  2. (United Kingdom)
  3. Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY (United Kingdom)
  4. Centre for Renewable Energy Systems Technology, School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire LE11 3TU (United Kingdom)
Publication Date:
OSTI Identifier:
22317996
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CADMIUM CHLORIDES; CADMIUM TELLURIDE SOLAR CELLS; CADMIUM TELLURIDES; DEFECTS; PHOTOVOLTAIC EFFECT; SEMICONDUCTOR MATERIALS; STACKING FAULTS; THIN FILMS

Citation Formats

Yoo, Su-Hyun, Walsh, Aron, E-mail: a.walsh@bath.ac.uk, Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY, Butler, Keith T., Soon, Aloysius, Abbas, Ali, and Walls, John M., E-mail: j.m.wall@loughborough.ac.uk. Identification of critical stacking faults in thin-film CdTe solar cells. United States: N. p., 2014. Web. doi:10.1063/1.4892844.
Yoo, Su-Hyun, Walsh, Aron, E-mail: a.walsh@bath.ac.uk, Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY, Butler, Keith T., Soon, Aloysius, Abbas, Ali, & Walls, John M., E-mail: j.m.wall@loughborough.ac.uk. Identification of critical stacking faults in thin-film CdTe solar cells. United States. doi:10.1063/1.4892844.
Yoo, Su-Hyun, Walsh, Aron, E-mail: a.walsh@bath.ac.uk, Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY, Butler, Keith T., Soon, Aloysius, Abbas, Ali, and Walls, John M., E-mail: j.m.wall@loughborough.ac.uk. Mon . "Identification of critical stacking faults in thin-film CdTe solar cells". United States. doi:10.1063/1.4892844.
@article{osti_22317996,
title = {Identification of critical stacking faults in thin-film CdTe solar cells},
author = {Yoo, Su-Hyun and Walsh, Aron, E-mail: a.walsh@bath.ac.uk and Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY and Butler, Keith T. and Soon, Aloysius and Abbas, Ali and Walls, John M., E-mail: j.m.wall@loughborough.ac.uk},
abstractNote = {Cadmium telluride (CdTe) is a p-type semiconductor used in thin-film solar cells. To achieve high light-to-electricity conversion, annealing in the presence of CdCl{sub 2} is essential, but the underlying mechanism is still under debate. Recent evidence suggests that a reduction in the high density of stacking faults in the CdTe grains is a key process that occurs during the chemical treatment. A range of stacking faults, including intrinsic, extrinsic, and twin boundary, are computationally investigated to identify the extended defects that limit performance. The low-energy faults are found to be electrically benign, while a number of higher energy faults, consistent with atomic-resolution micrographs, are predicted to be hole traps with fluctuations in the local electrostatic potential. It is expected that stacking faults will also be important for other thin-film photovoltaic technologies.},
doi = {10.1063/1.4892844},
journal = {Applied Physics Letters},
number = 6,
volume = 105,
place = {United States},
year = {Mon Aug 11 00:00:00 EDT 2014},
month = {Mon Aug 11 00:00:00 EDT 2014}
}
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