Structural and optical studies of cadmium doped zinc oxide thin films for solar cells

摘要

This study traces the effect of cadmium doping on structural and optical properties of ZnO in order to tailor energy band gap of cadmium doped ZnO thin films for solar cell applications. Sol-gel spin coating method has been deployed to deposit nanocrystalline films of cadmium doped ZnO on glass substrates at room temperature. These films were thermally annealed at 773 K in order to enhance crystallinity. High resolution X-ray diffraction studies facilitate phase analysis, while optical absorbance and transmittance studies suggest a decrease in energy band gap with increasing cadmium content. Maximum dopant concentration of 30% Cd in as-deposited films induced lowering of band gap from 3.29 eV to 2.85 eV.