Modified chemical deposition and physico-chemical properties of copper(I) selenide thin films

Semiconducting stoichiometric copper(I) selenide (Cu2Se) thin films were deposited onto glass substrate using a modified chemical method. The deposition conditions such as concentration and pH of cation and anionic precursor solutions, immersion and rinsing times and number of immersions, etc. were optimized for Cu2Se films. The characterization of Cu2Se films was carried out by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Rutherford back scattering (RBS), optical absorption/transmittance, electrical resistivity and thermoemf measurement techniques. The XRD shows the formation of copper(I) selenide with monoclinic crystal structure. Absorbance of the Cu2Se thin film is found to be high (104 cm−1) with optical band gap of 2.35 eV. The electrical resistivity is of the order of 10−1 Ω cm. Film exhibits p-type electrical conductivity.