Direct photochemical deposition of SiO2 from the Si2H6+O2 system

Abstract

Silicon dioxide films have been prepared by the direct photolysis of disilane with oxygen at temperatures as low as 150 °C. The photochemical deposition rate at temperatures below 300 °C has an activation energy of 0.53 eV, which is appreciably lower than the activation energy of 0.96 eV obtained for the thermal chemical vapor deposition (CVD). The infrared absorption peaks due to the SiH and SiOSi stretching modes in the photo-CVD SiO2 matrix always appear at higher wave numbers than those in thermal CVD films. This is interpreted in terms of the densification of the SiO2 network through photochemical reactions.