Photoinduced paramagnetic defects in amorphous silicon dioxide

Abstract

Several paramagnetic defects are photoinduced in amorphous Si${\mathrm{O}}_{2}$ by sub-band-gap light. The resulting EPR spectrum changes dramatically as the excitation energy is varied, and is sensitive to the OH content of the material. A three-component resonance seen in high-OH-content Si${\mathrm{O}}_{2}$ is ascribed to a nitrogen-impurity-related defect.