High‐rate preparation of thin Si films by atmospheric‐pressure plasma enhanced chemical transport

Abstract

AbstractPolycrystalline Si films were prepared by chemical transport using near‐atmospheric‐pressure pure hydrogen plasma (6.7 × 10−3 to 5.3 × 10−2 MPa). Substrate temperatures were varied from 200 to 600 °C and solid Si source was used as the feedstock to generate SiHx species. To generate high‐density stable glow hydrogen plasma at near atmospheric pressure, 150 MHz very high frequency (VHF) power was used. The dependence of deposition rate on various preparation parameters, such as VHF input power, hydrogen pressure, and substrate temperature, was investigated. The deposition rate increased with increasing VHF power density and substrate temperature. The attained deposition rate on glass substrates was 15 nm/s at 400 °C. Prepared Si films exhibited columnar structures along the growth direction. The maximum lateral grain size was 5 µm at the film thickness of 15 µm. It was found by Raman spectroscopy that the crystalline fraction of prepared Si film would not be influenced with increasing deposition rate (Rd). Copyright © 2008 John Wiley & Sons, Ltd.