Optical and Compositional Properties of CuInSe2 Thin Films at High Temperature

Abstract

Thin films of CuInSe2 are prepared by vacuum evaporation system on Al substrates and heated between 480 to 520°C under vacuum of 3 × 10−3 Pa for 2 h in Se atmosphere. X‐ray diffraction patterns show that the chalcopyrite structure of CuInSe2 transforms to cubic sphalerite type with a = 0.40448 ± 0.0055 nm. PL spectra show sharper lines with the disappearance of B3 transition. AES and XPS profiles show Cu diffusion after heat treatment while EPMA measurements show an excess of Cu concentration and Se deficiency.