Atomic force microscopy (AFM) and X-ray diffraction (XRD) investigations of copper thin films prepared by dc magnetron sputtering technique

Abstract

This paper addresses the influences of sputtering power and deposition pressure on the surface morphology and structural behavior of dc magnetron sputter-deposited copper (Cu) thin films on p-type silicon grown at room temperature. Results from our experiments show that the deposition rate of the Cu film increases proportionally with the sputtering power and decreases with deposition pressure. From the atomic force microscopy (AFM) and X-ray diffraction (XRD) analysis, high sputtering power enhances the microstructure of the Cu film through the surface diffusion mechanism of the adatom. The poor microstructure as a result of low sputtering power deposition was manifested with the smaller value of Cu film root mean square (RMS) roughness obtained. The deposition pressure has the contrary influence on structural properties of Cu film in which high deposition pressure favors the formation of voided boundaries film structure with degraded film crystallinity due to the shadowing effect, which varies with different deposition pressures.