Electrical Properties of Nanocrystalline CuxO Thin Films Prepared by r. f. Sputtering Method

Abstract

Nanocrystalline CuxO (0 < x < 1) thin films have been synthesized using r. f. sputtering method at different r. f. power in an atmosphere of O2 and Ar. The effect of varying r. f. power, oxygen partial pressure and film thickness during deposition on the crystal size and electrical properties of CuxO thin films have been studied. The films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and four-point electrical-resistivity probe measurements. The nanocrystallite size in these films was varied by varying deposition parameters. The electrical sheet resistance of the films was found to vary from 6.5 × 103 W/square for films prepared at 250 W r .f. power to as high as 2.78 W/square for films prepared at 400 W r. f. power. The variation in the electrical resistivity of the films with deposition conditions has been explained in terms of stoichiometric changes induced by copper or oxygen ion vacancies and neutral defects. The piezoelectric properties of the deposited films have been carried out.

Keywords: CuxO, r. f. sputtering, electrical properties; nanocrystalline thin films; piezoelectric properties