Effect of substrate temperature on some of the optical parameters of CuInS2 films

Abstract

Polycrystalline CuInS2 films have been grown by spray pyrolysis method at different substrate temperatures, a simple method which can produce low cost and highly absorbing samples. Optical characteristics of the CuInS2 films have been analyzed using spectrophoto meter in the wavelength range of 400-900 nm. The absorption spectra of the films showed that this compound is a direct band gap material and gap values varied between 1.51-1.80 eV, depending on the substrate temperatures. The refractive index n, extinction coefficient k and dielectric constants epsilon(1) and epsilon(2) were also discussed and calculated as a function of wavelength A