Fabrication and Characterization of Oxide Heterojunctions Prepared by Electrodepositing Cuprous Oxide on Conductive Glasses

Abstract

The properties of oxide heterojunctions prepared by electrodepositing Cu2O on commercial F-doped SnO2 (FTO) and Sn-doped In2O3 (ITO) glasses were studied. The X-ray diffraction patterns showed that Cu2O films grown on both FTO and ITO glasses are mainly (111)-oriented. The optical band gap of the electrodeposited Cu2O films grown on FTO glass determined from the absorption spectrum is about 2 eV. A peak with a wavelength of 622 nm that could be correlated to the near band edge emission was observed in the photoluminescence spectrum. Nonlinear and rectifying behaviors were observed in the current–voltage measurements of these fabricated heterojunctions. Furthermore, the high turn-on voltage of 4.7 V indicates the absence of defect states at the interface of the Cu2O/FTO heterojunction. Moreover, thermal annealing on Cu2O/FTO heterojunctions may cause Cu diffusion into the n-type layers.