Study of optical properties of pure and Sn doped ZnO thin films prepared by chemical spray pyrolysis method


Study of the optical properties of ZnO thin films Undoped and Sn-doped with doping percentage of (1%,3%,5%,7%) have been prepared on glass substrate at(450ºC) using chemical spray pyrolysis method , from during absorption and transmission spectra has been recorded in the wavelength range(380-900)nm,we have calculated energy gap in the allowed direct electron transition, it was found that the energy gap increased as the doping percentage increased, on contrary with urbach energy which decrease as the doping percentage increase,and calculated optical constant (Absorption, Transmission, reflectance, extinction coefficieent ,refractive index and dielectric constant in its two parts, Optical conductivity),The results shown that all these parameters in this research were affected by doping.