OPTICAL CHARACTERIZATIONS OF PHOTOINDUCED CHEMICAL-VAPOR-DEPOSITION PRODUCED SIO2-FILMS IN VACUUM-ULTRAVIOLET, ULTRAVIOLET, AND VISIBLE REGION

Photoluminescence and absorption properties of photo-induced chemical vapor deposition produced SiO2 films have been studied to identify the defects and the other imperfections. Two kinds of distinct absorption peak have been found which lie at 6.3 eV for low temperature deposition (around 30-degrees-C), and at 7.6 eV for high temperature deposition (around 300-degrees-C). Photoluminescence peaks at 2.7, 3.6-3.8, and 4.4 eV are found in the film deposited at high temperature, but the 4.4 eV peak is not seen in film deposited at low temperature. Intensity changes of the photoluminescence and absorption peaks have been obtained in various films which were deposited at different gas-flow-rate-ratios of Si2H6/O2 and were annealed in O2 and N2 ambients. It is considered from the treatment dependence of these peaks that the absorption peak at 7.6 eV and photoluminescence peak at 2.7 eV are attributable to oxygen-vacancies, but the absorption peak at 6.3 eV relates to oxygen-excess defects.