SURFACE-REACTION OF CF2 RADICALS FOR FLUOROCARBON FILM FORMATION IN SIO2 SI SELECTIVE ETCHING PROCESS/

The surface reaction of CF2 radicals on Si and fluorocarbon films was investigated in electron cyclotron resonance (ECR) Ar and H-2/Ar downs tream plasmas employing CF2 radical injection technique. The effects o f Ar+ ions, Ar metastable species and radiation from plasmas on the f luorocarbon film formation were evaluated in ECR Ar downstream plasma with CF2 radical injection. As a result, CF2 radicals with assistance of Ar+ ion bombardment were found to play an important role in the flu orocarbon film formation. The adsorptive reactions of CF2 radicals on the fluorocarbon film surface with and without Ar and H-2/Ar plasma ex posures were successfully investigated by in situ Fourier transform in frared reflection absorption spectroscopy and in situ x-ray photoelect ron spectroscopy. It was found that the formation of fluorocarbon film in the plasma proceeded through the adsorptive reaction of CF2 radica ls at a high probability on the active sites formed by the bombardment of Ar+ ions on the fluorocarbon film surface. (C) 1998 American Vacuu m Society.