Sputter Power Influenced Structural, Electrical, and Optical Behaviour of Nanocrystalline CuNiO 2 Films Formed by RF Magnetron Sputtering

Abstract

Copper nickel oxide (CuNiO 2 ) films were deposited on glass and silicon substrates using RF magnetron sputtering of equimolar Cu 50 Ni 50 alloy target at different sputter powers in the range of 3.1–6.1 W/cm 2 . The effect of sputter power on the chemical composition, crystallographic structure, chemical binding configuration, surface morphology, and electrical and optical properties of CuNiO 2 films was investigated. The films formed at sputter power of 5.1 W/cm 2 were of nearly stoichiometric CuNiO 2 . Fourier transform infrared spectroscopic studies indicated the presence of the characteristic vibrational bands of copper nickel oxide. The nanocrystalline CuNiO 2 films were formed with the increase in grain size from 75 to 120 nm as the sputter power increased from 3.1 to 5.1 W/cm 2 . The stoichiometric CuNiO 2 films formed at sputter power of 5.1 W/cm 2 exhibited electrical resistivity of 27 Ωcm, Hall mobility of 21 cm 2 /Vsec, and optical bandgap of 1.93 eV.