Characteristics of molybdenum-containing a-C:H films deposited using electron cyclotron resonance CVD

Metal-containing carbon (Me-C:H) films are presently attracting wide interests due to their unique properties such as good adhesion, low resistivity and friction value. As a result, numerous techniques for depositing such films have been proposed. In this paper, a novel technique which involves the incorporation of two molybdenum (Mo) screen grids embedded in an electron cyclotron resonance chemical vapor deposition (ECR-CVD) system is presented. A set of film deposition experiments based on this screen grid sputtering technique has been carried out. The Mo-containing carbon films were characterized using x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS). The changes in film resistivity were evaluated as a function of changes in the gas flow ratio (CH4/Ar). XPS analysis showed that the fraction of Mo incorporated in the carbon dim decreases drastically from 15.11% to 0.32% following an increase in the CH4/Ar flow ratio. The film resistivity was found to increase by 11 orders of magnitude following the decrease in the metal fraction. It is found that Mo can exist in the forms of MoC, Mo2C, Mo, and even MoO3 in the films, the last being mainly due to air exposure. The results showed that our ECR-based screen grid deposition technique for Me-C:H is highly effective and flexible with good control over the amount of metal incorporated.