Effect of Li Doping on Structural, Optical, and Electrical Properties of CuO Thin Films Produced by Spray Pyrolysis Method

Abstract

In the present work, structural, optical, and electrical properties of lithium-doped (0–6 at.%) copper oxide thin films were investigated. The films were obtained by the spray pyrolysis method on glass substrates at 450◦C. The X-ray diffraction method, UV-visible spectroscopy, and the four-point probe technique were used to analyze the films. Based on the X-ray diffraction investigations, it was found that the polycrystalline films have monoclinic phases with preferred (111) and (1̄11) crystallographic planes. The incorporation of lithium doping into the copper oxide thin film yielded crystallite sizes of approximately 2 nm. The estimated optical band gap values are decreased from 1.88 to 1.64 eV with increasing lithium concentration. Four-point probe studies revealed that the resistivity of the films decreased from 339 to 186 K Ω cm with increasing lithium concentration.