SURFACE REACTION OF CF2 RADICAL WITH Ar ION BOMBARDMENT IN FLUOROCARBON FILM FORMATION OR HIGHLY SELECTIVE SiO2/Si ETCHING

摘要

The surface reaction of CF2 radicals on Si and fluorocarbon films was investigated in electron cyclotron resonance (ECR) Ar and Hb/Ar downstream plasmas employing CF2 radical injection technique. The effects of Ar+ ions on the fluorocarbon film formation were evaluated in ECR Ar downstream plasma with CF2 radical injection. As a result, Ar+ ions with assistance of CF2 radicals were found to play an important role in the fluorocarbon film formation. The adsorptive reactions of CF2 radicals on the fluorocarbon film surface exposed to Ar and H2/Ar plasma were successfully investigated by in-situ Fourier transform infrared reflection absorption spectroscopy (FT-IR RAS) and in-situ X-ray photoelectron spectroscopy (XPS). It was found that the formation of fluorocarbon film in the plasma proceeded through the adsorptive reaction of CF2 radicals at a high probability on the active sites formed by the bombardment of Ar+ ions on the fluorocarbon film surface.