Cz-grown, carbon-doped silicon samples were irradiated by fast neutrons.
We investigated the annealing behaviour of oxygen-related defects, by
infrared spectroscopy. We studied the reaction channels leading to the
formation of various VmOn defects and in particular the VOn defects
formed by the accumulation of oxygen atoms and vacancies in the
initially produced by the irradiation VO defects, as the annealing
temperature ramps upwards. We mainly focused on bands appearing in the
spectra above 450 degrees C. A band at 1005 cm(-1) is found to be the
convolution of two bands at 1004 and 1009 cm(-1). The latter band has
the same thermal stability with the 983 cm(-1) of the VO4 defect and
therefore is also attributed to this defect. The former band has the
same thermal stability with three other bands at 965, 1034 and 1048
cm(-1). These four bands may be attributed to VOn (n=5,6) defects,
although other VmOn complexes are also potential candidates.
Furthermore, we found that pre-treatments of the samples at 1000 degrees
C, with or without the application of high hydrostatic pressure lead to
an increase in the concentration of the VO2, VO3 and generally VOn
defects in comparison with that of the untreated samples
