OPEN-AIR DEPOSITION OF SIO2 FILM FROM A COLD-PLASMA TORCH OF TETRAMETHOXYSILANE-H2-AR SYSTEM

A rf plasma beam was generated in the stream of atmospheric pressure a rgon to be exhausted from a cylindrical nozzle into air. The temperatu re measurements indicate a nonequilibrium low temperature nature of th is plasma. By using this cold plasma torch, films were deposited on th e substrates placed in air at growth rates higher than 100 angstrom/s by feeding tetramethoxysilane into the plasma. Fourier transform infra red spectroscopy and x-ray photoelectron spectroscopy revealed that th e films were essentially SiO2 and their structures and properties coul d be improved by admixing hydrogen in the plasma. The SiO2 films depos ited at a rate of 120 angstrom/s from Si(OCH3)4-H-2-Ar plasma had surf aces as smooth and hard as Coming 7059 glass.