Studies of deep levels in high resistivity silicon detectors irradiated by high fluence fast neutrons using a thermally stimulated current spectrometer

Measurements of deep level spectra for high resistivity silicon detectors irradiated by high fluence fast neutrons (up to 10(14) n/cm2) have been performed using a Thermally Stimulated Current (TSC) spectrometer. Nine new defect levels, with peaking temperatures of respectively 26K, 34K, 41K, 47K, 90K, 110K, 135K, 147K and 155K begin to appear for flunces over 10(13) n/cm2. All peaks are strongly dependent on the filling forward voltage. V(fill), or injection current, especially for high fluences of irradiations. Energy levels inside the band gap and trap concentrations corresponding to each of the TSC peaks, totaling at most 18, have been studied systematically and possible relations to lattice defects have been discussed.