Investigation of Electronic and Optical Properties of Thin Films of Copper Oxides Deposited by Low-Pressure Arc Discharge

Abstract—In this investigation, thin films of copper oxides obtained by arc deposition at low pressure on borosilicate glass are studied. The phase composition, structural characteristics, and chemical state of the samples are confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. Hall measurements using the van der Pauw method show that films of both Cu2O and CuO phase compositions have hole conductivity (p-type). The concentration of charge carriers, mobility, and resistivity of the samples are determined. The formation of a heterojunction with a significant decrease in the concentration of charge carriers due to the recombination of electron–hole pairs is observed in a thin film of mixed composition (Cu2O/CuO). From UV-visible spectroscopy measurements, the absorption/transmission characteristics of the films are determined and the optical band gap is calculated. It is shown that change in the phase composition of the oxide from Cu2O to CuO leads to a decrease in the band gap from 1.90 to 1.34 eV.