Internal stress and adhesion of Cu film/Si prepared by both MEVVA and IBAD

Abstract

Three groups of copper films were deposited on the surfaces of the Si (100) crystal by both metal vapor vacuum arc (MEVVA) ion implantation and ion beam assistant deposition (IBAD) technologies. Before coating Cu film by IBAD two groups of the samples were implanted by 68 keV Cu ion with fluence of 3 × 10 17 ions/cm 2. Different sputtering ion densities and deposition times of IBAD were selected for three groups of the samples. The internal stresses in the copper films were analyzed by X-ray diffraction (XRD). The morphologies of the copper films and cross-section micrographs were observed by scanning electron microscopy (SEM). The adhesive strength of the Cu films was measured by a nano indenter. The experimental data indicate that all the copper films possessed compressive stress, which was increased as the film thickness increased. The internal stresses of the samples prepared without Cu ion implantation were minimum among three groups of the samples. The adhesive strength of the samples prepared with MEVVA ion implantation was much higher than one of the samples prepared without MEVVA ion implantation.