Deposition of SiO2 Films from ArF Laser Photolysis of SiH4/N2O Mixtures

Deposition of SiO2 thin films by the ArF excimer laser photolysis of mixtures of SiH4 and N2O has been studied in the low substrate temperature range of 30-400°C. The structural properties of the oxide layers were studied by FT-IR spectroscopy. The refractive index of films agreed with that of stoichiometric SiO2 in the substrate temperature range of 150-400°C. The deposition conditions were studied as a function of the substrate temperature, the deposition time, the laser repetition rate, the total pressure, and the N2O/SiH4 flow ratio. The maximum growth rate was ∼70 Å/min at a substrate temperature of 400°C, a total pressure of 2 Torr, a repetition rate of 50 Hz, and a N2O/SiH4 flow ratio of ∼800.