Structural properties and refractive index dispersion of cobalt doped SnO2 thin films

Tin dioxide and cobalt doped tin dioxide thin films were prepared using chemical spray pyrolysis. X-ray diffraction study showed that the deposited films exhibited tetragonal structure with (110) plane as the preferred orientation. The AFM study showed that the rms roughness of undoped films reduced from 20.7 to 15.2 nm due to cobalt doping. The refractive index dispersion curves of undoped and cobalt doped SnO2 thin films obeyed the single oscillator model. The dispersion parameter E-d was found to increase as the doping content was increased, while oscillator energy E-o was found to decrease.