Preparation of SiO₂Film by Photo-Induced Chemical Vapor Deposition Using a Deuterium Lamp and Its Annealing Effect

Silicon dioxide thin films have been prepared at low temperatures from SiH 4 and O 2 by direct photo-induced CVD using a deuterium lamp. The growth rate is 75 Å/min at 84°C while no growth occurs below 180°C without deuterium lamp irradiation. UV and VUV light irradiation and an increase of the substrate temperature have effects of increasing the refractive index, and decreasing H incorporation and the amount of the oxide charge. The photo-CVD films deposited above 180°C show refractive indices of 1.45–1.46. Annealing in an O 2 environment decreases the infrared absorptions due to Si–H stretching, Si–OH deformation and Si 2 O 3 bondings as well as the oxide charge. The activation energies of the Si–H, the Si–OH deformation, the Si 2 O 3 and the oxide charge obtained from the annealing characteristics are 0.18–0.19, 0.12, 0.19 and 0.12–0.13 eV, respectively. The reduction of Si–OH deformation absorption is considered to be closely related to the reduction of oxide charge.