Optical Emission Analysis of Atmospheric Pressure Methane Plasma Chemical Vapor Deposition

The distinctive glow features of low-temperature RF CH4/Ar plasma chemical vapor deposition and its correlation with plasma-deposited film characterizations were investigated. The optical emission spectroscopy diagnosis data and deposition results clearly indicated that, during CH4/Ar glow discharge, the CH and C2 species resulted from the low-energy electron-impact dissociation of CH4 molecules that formed the deposition species, but the strong Ar emission lines were related to nondeposition species such as the argon atom. The results of the optical emission analysis indicated that the possible contribution of atmospheric pressure plasma-deposited film growth occurs primarily owing to a combination of electron-impact–dissociation and ionization.