Rectifying properties of ZnO thin films deposited on FTO by electrodeposition technique

Abstract ZnO thin films were successfully grown on fluorine-doped tin oxide glass by electrodeposition technique. The crystal structure, surface morphology and optical properties of the thin films were investigated. The average crystallite size and intensity of A 1 (LO) mode increase with improving the absolute value of deposition potential. The best preferential orientation along c -axis and the richest oxygen interstitial defects have been observed in the sample deposited at −0.8 V. A heterojunction device consisting of ZnO thin film and n-type fluorine-doped tin oxide was fabricated. The current–voltage ( I – V ) characteristic of the p–n heterojunction device deposited at −0.8 V shows the best rectifying diode behavior. The p-type conductivity of the ZnO thin film could be attributed to complex defect of unintentional impurity and interstitial oxygen.