Cu-In-O composite thin films deposited by reactive DC magnetron sputtering

►Cu-In-O composite thin films were fabricated by DC sputtering at room temperature. ►The films are made of rhombohedral In2O3 and monoclinic CuO. ►The transmittance depends on the Cu content in the film. ►The direct optical band gap is around 4.1-4.4eV. ►The conducting mechanism is due to oxygen vacancy.