Characterization of n and p-type (SnO2)x(ZnO)1-x nanoparticles thin films

Electron beam evaporation technique was used to deposit (SnO2)x(ZnO)1-x thin films with different concentrations of SnO2 and ZnO. Optical transmittance (T) and reflectance (R) of the films were measured in the wavelength range 200–2500 nm. It was found that the optical properties of the films are strongly affected by the ratio of Sn content. The optical energy gaps of direct and indirect transition for the films were determined. Values of energy gap were in the range from 3.35 to 4 eV for direct transition, and from 2.53 to 3.43 eV for indirect transition. The electrical resistivity of the films was measured by means of two contact method. Values of electrical resistivity were in the range between 5.06 × 10-4 and 1.55 × 102 Ω cm depending on the ratio of Sn and Zn ratios. A transformation from n-type to p-type semiconductors was observed.