Numerical Analysis of Substrate-Incident Carbon Flux in Low-Pressure Radio-Frequency CH4 Plasmas for Deposition of Diamond-Like Carbon Films

SUMMARY Capacitively coupled hydrocarbon (CH4) plasmas used in the deposition of diamond‐like carbon films have been simulated using a self‐consistent one‐dimensional fluid model, incorporating the mass balance equations for electrons, ions, radicals, and nonradicals, as well as the electron energy balance equation, coupled with the Poisson equation. Despite the conditions in the low‐pressure CH4 gas, many positive‐ion species, such as C2H4+, CH4+, C2H2+, and CH5+ have been found in the plasmas. Nonradical neutrals such as C2H4, C3H8, C2H2, and C2H6, have also been found at higher densities comparable to the source gas density. This result indicates that this complexity in the background gas of CH4 plasmas has a substantial effect on the electron energy distribution function, which is important when making determinations about the plasmas properties.