Investigation of the structural, optical and electrical transport properties of n-doped CdSethin films

Abstract

Thin films of (CdSe)90(In2O3)10, (CdSe)90(SnO2)10 and (CdSe)90(ZnO)10 have been grown on glass substrates by the electron beam evaporationtechnique. It has been found that undoped and Sn or In doped CdSefilms have two direct transitions corresponding to the energy gapsEg and Eg+Δ due to spin–orbit splitting of the valence band. The electrical resistivity for n-doped CdSethin films as a function of light exposure time has been studied. The influence of doping onthe structural, optical and electrical characteristics of In doped CdSe films hasbeen investigated in detail. The lattice parameters, grain size and dislocationwere determined from x-ray diffraction patterns. The optical transmittance andband gap of these films were determined using a double beam spectrophotometer.The DC conductivity of the films was measured in vacuum using a two-probetechnique.