Voltage-Current Characteristics of Heterojunctions Prepared from Anodic-Oxidized ZnO Films and RF-Sputtered Pr-Co-O Thin Films

Abstract

ZnO films were prepared by anodic-oxidation of Zn metal plates at various anodic-oxidation conditions. Pr-Co-O thin films having various Co contents were deposited on the ZnO films by radio-frequency (RF) magnetron sputtering for the formation of heterojunctions. Nonlinear properties were observed in voltagecurrent (V-I) characteristics of the heterojunctions, and the threshold voltage shifted to the lower voltage side with increasing Co contents in the Pr-Co-O thin films. The nonlinearity coefficients α in the V-I characteristics became large as about 30 when transparent ZnO films were used.