Transparent conductive oxide (TCOs) materials still occupy the attention of many scientific researchers because of their important properties including high transmittance and high electrical conductivity. The doping process whether intrinsic or extrinsic materials. For example, elements of Group-III doped ZnO (B,Al,In,Ga) and group IV (Sn,Pb) has led to changes in optoelectronic properties [An H., 2014, Mahmoud W.E.,2011, Bae S.Y.,2005, Lee J.H.,2003, and Natsume Y.,1992]. In this research, The influence of SnO2 doped ZnO will be under studied.
Electron beam evaporation technique was used to deposit (SnO2)x(ZnO)100-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. Finally, The film resistivity was measured in the 80-475 K temperature range and the optical band gap (Eg) were investigated.
The films exhibit an amorphous structure. The optical properties of the films strongly affected by the ratio of Sn content. Values of energy gap was in the range from 3.35 to 4 eV for direct transition, whereas for indirect transition was in the range from 2.53 to 3.43 eV. Values of electrical resistivity were in the range between 5.06 x 10-4 to 155 W cm depending on the ratio of Sn and Zn ratios. Such a transformation from n-type to p-type semiconductors was observed.