The crystal structure and photoresponse of ZnO thin films fabricated on ITO substrates

The influence of different RF-power on the crystal structures, surface morphologies and optical properties of ZnO thin films fabricated on ITO (ln₂O₃: Sn) substrates was investigated. With the increase of RF-power, the crystal quality of c-axis oriented ZnO thin films is improved dramatically; The grain size decreases slightly, which was determined by atomic force microscopy (AFM); the roughness of ZnO thin films decreases from 13.13 nm to 5.06 nm; the optical transmittance of ZnO/ITO/glass decreases in the wavelength range from 300 nm to 400 nm. The existence of inner electric field in the interface of double layer is responsible for the effective separation between electrons and holes, which provides a good photoresponse and 14μ A photocurrent. This means the ZnO/ITO has great application potential on photovoltaic field and can be used as the electrode materials with high photocurrent and short response time.