Influences of CuO doping on the properties of ZnO films by RF magnetron sputtering

In this study, the zinc oxide thin films were prepared by magnetron sputtering on alkali-free borosilicate glass substrates. The doping level of CuO in the ZnO targets varied from 2 to 10 at% during the preparation process to investigate its influence on the properties of ZnO films. All of CuO doped ZnO thin films grew along the preferential (002) crystal plane, with the diffraction intensity of (103) plane being lower at 4 at%, decreasing upon increasing the CuO concentration from 2 to 4 at% and increasing upon increasing the CuO concentration from 4 to 10 at%. The transmittance, as well as the optical band gap, in the wavelength range of visible light (400-700 nm) decreased upon increasing CuO concentration. The resistivity increased upon increasing CuO concentration, duo to the increasing V
_o
concentration and the increasing density of grain boundaries.