• Bär, M.; Schubert, B.-A.; Wilks, R.G.; Marsen, B.; Zhang, Y.; Blum, M.; Krause, S.; Yang, W.; Unold, T.; Weinhardt, L.; Heske, C.; Schock, H.-W.: Identification of Impurity Phases in Cu2ZnSnS4 Thin-film Solar Cell Absorber Material by Soft X-ray Absorption Spectroscopy. In: Bell, L.D. [u.a.] [Eds.] : Compound semiconductors for energy applications and environmental sustainability - 2011 : symposium held April 25 - 29, 2011, San Francisco, California, U.S.A. ; [Symposium D "Compound Semiconductors for Energy Applications and Environmental Sustainability" ... at the 2011 MRS spring meeting]New York, NY: Cambridge Univ. Press, 2011 (Materials Research Society symposium proceedings ; 1324). - ISBN 978-1-605-11301-2, p. mrs11-1324-d15-19/1-6


Abstract:
The composition of Cu2ZnSnS4 thin-film solar cell absorbers was varied to induce the formation of secondary impurity phases. For their identification, the samples have been investigated by Cu L3 and S L2,3 soft x-ray absorption (XAS) spectroscopy. We find that Cu L3 XAS is especially sensitive to the presence of copper sulfides as well as copper oxides and/or changes in the electron configuration, suggesting a basis for future studies of the surface, defect, and interface characterization of similar samples. Additionally, it is shown that the S L2,3 absorption data can be used as a very sensitive probe of the variations in the prevalence of S-Zn bonds in the near-surface region of the investigated samples.