Effective low power microwave plasma CVD of carbon nitride films

摘要

A new type of microwave plasma source was applied for high rate low power PE CVD of carbon nitride films. The source is based on a modified waveguide surfatron where the plasma slab is substituted by a metallic antenna. This original arrangement allows to generate a ball-shaped plasma, located at the tip of the antenna close to the substrate surface, at very low microwave powers. The tubular antenna served as an inlet of the gas ixture consisting of nitrogen and acetlyene. Films were deposited through a circular window of 2 (or 3) cm in diameter onto Si, Al, glass, plastics and paper substrates. The film depsotion rates were about 1 mu m/ming already at 10 W of the absorbed microwave power. Maximum rates exceeding 3 mu m/min wer reached at 30 W with slight dependence on the substrate temperature. FIlm properties dependen on both the gas mixture and the substrate temperature. The XRD and soft X-ray spectra of 10 mu m thick C-N films deposited at temperatures below 400 deg C fonfirm an amorphous structure. However, the polycrystalline C-N phase were detected in hard films deposited at higher temperatures. Main features of the deposition processes are discussed with respect to the film properties.