Dresden 2014 – scientific programme

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HL: Fachverband Halbleiterphysik

HL 112: Energy materials: CIGS and related photovoltaics

HL 112.4: Talk

Friday, April 4, 2014, 10:15–10:30, POT 112

X-ray fluorescence on Cu(In,Ga)Se₂-lamellas — •Philipp Schöppe¹, Alexander Kusch¹, Michael Oertel¹, Claudia Sarah Schnohr¹, Andreas Johannes¹, Stefanie Eckner¹, Manfred Burghammer², and Carsten Ronning¹ — ¹Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany — ²European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble Cedex, France

Compositional and structural properties of the absorber affect significantly the efficiency of Cu(In,Ga)Se₂ solar cells. The integral composition is commonly determined using X-ray fluorescence (XRF) with high resolution. However, the absorber is typically inhomogeneous and thus there is a particular interest in collecting information from defined spatial regions in the nanometer range. Hence, XRF mapping with an X-ray beam diameter of approximately 200 to 300 nm was used to investigate cross sections of Cu(In,Ga)Se₂ solar cells. In order to implement this improved spatial resolution in the measurement, thin lamellas were prepared using a focused ion beam. Best results were obtained using a lamella thickness of about 250 nm. This enabled us to determine quantitatively the depth dependent composition of the absorber, particularly the Ga gradient, and its spatial distribution.