Characterization of the native oxide of CuInSe2 using synchrotron radiation photoemission

Synchrotron radiation soft x‐ray photoemission spectroscopy was used to investigate the native oxide of n‐type single‐crystal CuInSe2. Photoemission measurements were acquired on the oxide surface before and after removal using sputter etching. Observed changes in the valence‐band electronic structure as well as changes in the In 4d and Se 3d core lines were correlated with the interface chemistry at the oxide/CuInSe2 interface. These results show the native oxide to be composed of an In2O3 outer layer (no SeO2) with an additional Cu2Se interface layer.