Thin films of CuInSe2 prepared by RF sputtering from various compositional powder targets

CuInSe₂ thin films were prepared in the temperature range of 300–500°C by RF sputtering from powder targets, which were previously synthesized by reacting Cu, In, and Se in various ratios. The peaks from X-ray diffraction analyses were assigned to the planes of the CuInSe₂ chalcopyrite structure. The full width at half maximum of the (112) diffraction peak decreased with an increase in Cu/In ratio in the thin films. The photoelectron energies of the prepared thin films agreed with those reported for single crystalline CuInSe₂ from X-ray photoelectron spectroscopy measurements. The electronic conduction type and optical properties were found to change according to the Cu/In ratio in the thin films.