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Cu2ZnSnS4 thin-film solar cell absorbers illuminated by soft x-rays

Published online by Cambridge University Press:  20 March 2012

M. Bär*
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany; Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus, D-03046 Cottbus, Germany; and Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003
B.-A. Schubert
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany
B. Marsen
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany
R.G. Wilks
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany
M. Blum
Affiliation:
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003; and Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720
S. Krause
Affiliation:
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003
S. Pookpanratana
Affiliation:
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003
Y. Zhang
Affiliation:
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003; and Department of Physics, Xiamen University, Xiamen 361005, People’s Republic of China
T. Unold
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany
W. Yang
Affiliation:
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720
L. Weinhardt
Affiliation:
Exp. Physik VII, Universität Würzburg, D-97074 Würzburg, Germany
C. Heske
Affiliation:
Department of Chemistry, University of Nevada, Las Vegas, Las Vegas, Nevada 89154-4003
H.-W. Schock
Affiliation:
Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin, Germany
*
a)Address all correspondence to this author. e-mail: marcus.baer@helmholtz-berlin.de
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Abstract

In view of the complexity of thin-film solar cells, which are comprised of a multitude of layers, interfaces, surfaces, elements, impurities, etc., it is crucial to characterize and understand the chemical and electronic structure of these components. Because of the high complexity of the Cu2ZnSn(S,Se)4 compound semiconductor absorber material alone, this is particularly true for kesterite-based devices. Hence, this paper reviews our recent progress in the characterization of Cu2ZnSnS4 (CZTS) thin films. It is demonstrated that a combination of different soft x-ray spectroscopies is an extraordinarily powerful method for illuminating the chemical and electronic material characteristics from many different perspectives, ultimately resulting in a comprehensive picture of these properties. The focus of the article will be on secondary impurity phases, electronic structure, native oxidation, and the CZTS surface composition.

Type
Invited Feature Paper
Copyright
Copyright © Materials Research Society 2012

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References

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