The effect of laser irradiation on electrical and structural properties of ZnO thin films

In this paper، ZnO thin film was prepared by sol-gel process on glass substrates. The deposited films were dried at 100 and 240 ˚C and then annealed at 300، 400 and 500 ˚C. The two-probe measurement showed that resistance of as-prepared films is very high. The KrF excimer (λ=248 nm) laser irradiation with 1000 pulses، frequency of 1 Hz and 90 mJ/cm2 energy on surface of film resulted in the reduction of the films electrical resistance. X-ray diffraction (XRD) patterns confirmed the improved hexagonal wurtzite structure of film، and AFM and FE-SEM analyses showed regular and spherical grain was formed on the surface. The particle size was increased from ~10 to ~30 nm after leaser irradiation. Generally، it was showed that electrical، structural and morphological properties of films improve considerably by laser irradiation.