Preparation and characterization of p- NiO:Li thin films as schottky photodiode

Abstract

Nickel oxide was prepared using the chemical method. Li-doped NiO thin films with concentrations (0.04) was deposited on glass substrate using drop casting technique with thickness 150nm, and then the annealing at 300 ° C for 60 sec. The effect of the lithium doping on the structural and optical properties of Li: NiO films were examined. The structure of the prepared films were described by x-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The results of X-ray pattern showed the NiO and Li: NiO films to have a polycrystalline structure of a cubic type and preferred orientation (111). (AFM) data indicated that the structure was nanoscale and surface of the films is highly smooth. The study of optical properties included the transmittance spectrum of the prepared films of the wavelengths of (300-900) nm, It was found that the transmittance of pure nickel oxide is 79% in the visible area after doping by Li The transmittance decreases and the absorption increases. The energy gap was also calculated and found to be decreasing by increasing the doping concentration. Other important optical properties of the absorption coefficient and extinction coefficient were calculated. The electrical properties of the prepared films were studied, It was found that the concentration of the carriers increases with increasing doping concentration and mobility decreases. The thin films were deposited on a substrate of FTO to make of schottky diode. The characteristics of I-V, C-V were studied. A solar cell was found the efficiency of the cell was increased by doping.