OPTICAL-ABSORPTION OF THE NANOSTRUCTURED SIO2 IN ULTRAVIOLET NEAR-INFRARED LIGHT RANGE

The electronic structure of nanostructured SiO2 was studied by means o f ultraviolet-near infrared absorption spectra. A strong and broad abs orption hand was observed in the wavelength range of ultraviolet-near infrared light. This band is caused by the electronic transition from the valence band to the defect energy level in the band-gap which was theoretically calculated by using molecular orbital approach. With inc reasing the annealing temperature, the red shift of this band was obse rved. The mechanism of this band is discussed.