Tuning the optical and morphological features of CuxO thin films via La doping

Abstract

In the present investigation, the undoped and La doped CuxO thin films are deposited on glass substrates by sol-gel spin coating method. The effect of various La doping concentrations on the chemical composition, morphological and optical properties of CuxO thin films have been extensively studied using X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM), Scanning electron microscopy (SEM), and UV–Vis diffuse spectrophotometer. The valence states of Cu, La and O have been identified by X-ray photoelectron spectroscopy (XPS) method. The AFM have demonstrated that the surface roughness of CuxO thin films decreases with increasing La concentration. Optical analyses have revealed that the optical band gap energy of CuxO thin films widens from 2.063 eV to 2.090 eV as the La concentration increases from 0% to 10%. Moreover, the Urbach energies, Eu, of the undoped and La substituted CuxO thin films have been determined.