Growth and structural properties of hydrogenated silicon films deposited by pulsed laser ablation

Hydrogenated silicon thin films have been deposited by means of pulsed lase r ablation. Efficient hydrogenation was obtained by performing the ablation process in a controlled H-2 atmosphere. Fluorescence spectroscopy characte rization of the plume revealed the presence of both atomic hydrogen and hig hly ionized silicon atoms. The hydrogen content ranged from 2% to 15% as th e H-2 pressure was varied between 0.05 and 30 mbar. Infrared spectroscopy m easurements showed a monohydride preferential incorporation at low hydrogen pressure. The films' crystalline fraction, obtained by both Raman scatteri ng and x-ray diffraction experiments, was found to show a maximum value of about 60% for H-2 pressure values around 1 mbar. These results suggest that crystallinity and hydrogenation of the film, deposited at room temperature , can be properly adjusted as a function of the deposition parameters. (C) 1999 American Vacuum Society.