Marcus Bär, Björn-Arvid Schubert, Björn Marsen, Regan G. Wilks, Sujitra Pookpanratana, Monika Blum, Stefan Krause, Thomas Unold, Wan Li Yang, Lothar Weinhardt, Clemens Heske, Hans-Werner Schock
- The electronic structure of the CdS/Cu2ZnSnS4 (CZTS) heterojunction was investigated by direct and inverse photoemission. The effects of a KCN etch of the CZTS absorber prior to CdS deposition on the band alignment at the respective interface were studied. We find a “cliff”-like conduction band offset at the CdS/CZTS interface independent of absorber pretreatment and a significant etch-induced enhancement of the energetic barrier for charge carrier recombination across the CdS/CZTS interface.