  Influence of the prolonged irradiation by fission products of 252Cf
radionuclide on the operational parameters of silicon-lithium Si(Li) p-i-n
detectors, Si surface barrier detectors and Si planar p+n detector was
investigated. The obtained results revealed a linear shift of the fission
fragment peaks positions towards the lower energies with increase of the
irradiation dose for all investigated detectors. The rate of the peaks shift
was found to depend strongly on the detector type and the strength of the
electric field in the detectors active region, but not on the temperature of
irradiation (room or liquid nitrogen temperature). Based on the obtained
results, the possibility of integration of the investigated types of Si
semiconductor detectors in a radionuclide neutron calibration source is
considered.
