Growth - etching competitive mechanism governing the structure and chemical composition of plasma-deposited silicon-based materials

The plasma-enhanced chemical vapour deposition technique has been utilized to deposit silicon-carbon alloys from SiH4-CH4 and SiF4-CH4 glow discharges and silicon films from SiF4-H2-He mixtures. The silicon-based material deposition is shown to result from a competition between growth and etching reactions. Control of the two competitive channels is capable of determining the alloy composition and the amorphous-to-microcrystalline transition. Data from optical emission spectroscopy can provide a powerful tool for monitoring the channels governing the net material deposition rate.