Formation of Diamond-Like Carbon Thin Films by Using Surface Discharge Plasma under Atmospheric Pressure

Abstract

The deposition of diamond-like carbon (DLC) thin films was conducted by using surface discharge plasma under atmospheric pressure. The high-frequency surface discharge plasma was generated by applying a pulsed voltage between electrodes. The main radicals generated by the surface discharge were H, CH, and C2 by using H2, CH4, and He as plasma gases. The optical emission intensities of these radicals increased with increasing pulse width and decreasing pulse cycle of the applied pulse voltage. By increasing the length of the surface discharge, the ratios Hβ/Hα and C2/Hα increased. It was demonstrated that a hard DLC film can be obtained at a lower deposition rate under the experimental conditions.