Excimer laser reactive ablation deposition of silicon nitride films

Silicon nitride films were deposited on silicon wafers by XeCl (308 nm) excimer laser ablation of silicon in low pressure (1 × 10−3−1 mbar) ammonia atmospheres. Series of 10000 pulses at the repetition rate of 8 Hz were directed to the target surface. The fluence was set at about 5 J/cm2. Pulse duration was about 30 ns. The deposited films were characterized by different techniques (X-ray diffraction, infrared spectrophotometry, X-ray photoelectron spectroscopy, Auger electron spectroscopy, scanning electron microscopy, profilometry). Deposition of stoichiometric silicon nitride films with thickness close to 1 μm (deposition rate ∼ 0.1 nm/pulse) was obtained when ablation was performed in ammonia at the pressure of 1 mbar.