Zn1−xAlxO:Cu2O transparent metal oxide composite thin films by sol gel method

Abstract

We have synthesized undoped zinc oxide (ZnO) and Cu2O doped Zn1−XAlXO (AZO; Al/Zn = 1.5 at.%) metal oxide films by sol–gel spin coating method. Atomic force microscopy results indicate that the Zn1−xAlxO:Cu2O is are formed form the fibers. The surface morphology of the films is found to depend on the concentration of Cu2O. The optical constants such as band gap, Urbach energy, refractive index, extinction coefficient and dielectric constants of the films were determined. The transmittance spectra shows that all the films are highly transparent. The study revealed that undoped ZnO film has direct bang gap of 3.29 eV and the optical band gap of films is increased with doping content. The hot probe measurements indicate that Zn1−xAlxO:Cu2O transparent metal oxide composite thin films exhibited p-type electrical conductivity.