Shoulder at the 887 cm(-1) infrared band in neutron irradiated Si

Infrared spectroscopy was used to study the 887 cm(-1) band in neutron irra diated Czochralski-grown silicon arising in the spectra upon annealing of t he 830 cm(-1) band of the VO defect. Our analysis showed the presence of a 884 cm(-1) shoulder in the region of the 887 cm(-1) infrared band. The 887 cm(-1) band is generally attributed to the VO2 defect formed by the capture of a mobile VO center by an oxygen interstitial impurity. In our study the shoulder at 884 cm(-1) is tentatively correlated with the V3O defect. Semi empirical calculations carried out for the vibrational frequency of V3O str ucture gave a value at 883 cm(-1) thus corroborating the latter assignment. This new picture of the spectra in the range of the 887 cm(-1) band could explain some so far unaccounted for experimental findings previously report ed in literature. (C) 1999 American Institute of Physics. [S0021-8979(99)03 812-8].