Preparation of Nanocrystalline Copper Doped CdS Thin Films by Spray Pyrolysis Method


Nanocrystalline undoped and Cu-doped thin films have been prepared on glass substrates at 673 K by spray pyrolysis CSP. The effect of Cu-doped on structural and optical properties was studied. XRD data indicates the formation of hexagonal nanocrystalline CdS and CdS:Cu thin films, and Cu2+ ions entering the lattice substitutionally. The optical properties of these films were studied by measuring their optical transmission and their absorption spectra in the 300-900 nm range. The optical absorption studies reveal that the transition is direct with band gap value (2.417eV) for undoped and in the range (2.413-2.4eV) for doped films. Other important optical constants, such as extinction coefficient, refractive index and dielectric constant was calculated and analyzed.