Copper Nickel Oxide Thin Films Deposited by DC Sputtering for gas sensing applications

Abstract: Copper nickel oxide (CuNiO2) thin films were deposited onto unheated glass substrates by DC reactive magnetron sputtering the composite target of Cu50Ni50 at a fixed oxygen partial pressure of 3x10-4 mbar and sputter pressure of 3x10-2 mbar. The as-deposited copper nickel oxide films were annealed in air at temperature of 200oC in one hour. The as-deposited and annealed film was characterized for their chemical composition, electrical, optical and Hydrogen gas sensing properties. The as-deposited films were amorphous in nature. The electrical resistivity of the film increased with annealing temperature due to the filling of oxygen ion vacancies. The films annealed at 200oC exhibited the crystallite size of 25 nm, electrical resistivity of 12 Ωcm and optical band gap of 1.97 eV.

Keywords: CuNiO2 thin films, DC magnetron sputtering, Electrical, Optical and Hydrogen gas sensing properties.