衬底温度对CuCrO_2薄膜结构及光电性能的影响

Effect of substrate temperature on structural and optoelectronic properties of CuCrO_2 thin films

采用射频磁控溅射方法,在石英衬底上制备CuCrO_2薄膜。通过X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外吸收光谱以及电导率的测定,表征不同衬底温度沉积薄膜样品的结构与光电性能。结果表明:薄膜的结晶度、可见光透过率与室温电导率均随衬底温度的升高而增大。衬底温度升高至923 K后,薄膜由非晶转变为具有铜铁矿结构的单相CuCrO_2。1023 K沉积的薄膜光电性能最佳,其平均可见光透过率为50%,室温电导率为0.33 S/cm。在近室温区(150～300 K),1023 K沉积薄膜导电规律符合半导体热激活模式,激活能为0.04 eV。

CuCrO2 thin films were prepared by radio frequency magnetron sputtering on quartz substrates. The influence of substrate temperature on the structural and optoelectronic properties was investigated. XRD and XPS results show that923 K and 1023 K deposited films has a delafossite structure without other phases. The electrical conductivity and optical transmittance increase with the increase of substrate temperature. When the substrate temperature is 1023 K, the film has a higher optical transmittance and electrical conductivity. Its transparence in visible light is 50%, and the conductivity at room temperature is 0.33 S/cm. The temperature dependence of electrical conductivity agrees well with the Arrhenius rule in the temperature range of 150-300 K for the 1023 K deposited sample, and the activation energy is 0.04 eV.