Investigation of Fluorocarbon Film Deposition from Ar/CF4/H2 Plasma for the Implementation of the Atomic Layer Etching Process

Plasma was diagnosed using Langmuir probe and optical actinometry methods, and growth rates of films or etching of surfaces of functional layers from Ar/CF4/H2 plasma were investigated in a plasma etching setup. It was found that the deposition rate varies non-monotonically with the proportion of CF4 in the plasma, and the film deposition process is replaced by the SiO2 etching process. At high CF4 proportions in the plasma, the deposition rate is determined by the concentration of fluorocarbon radicals in the plasma. Understanding the kinetics of the fluorocarbon film deposition process enables optimization of the atomic layer etching process.