Shallow- and deep-levels analysis in irradiated medium-resistivity silicon detectors

The study analyzes the degradation of the electrical properties of siliconp+/n/n+ detectors with medium resistivities as a function of neutron irradiation in the fluence range from 6·4·1011 n/cm2 to 2·5·1015 n/cm2. The changes in the effective carrier concentration induced by irradiation and to the introduction with the fluence of deep levels. The shallow levels have been studied by thermally stimulated current (TSC) in the low-temperature range: a removal of one order of magnitude of the phosphorus concentration has been observed for fluences of the order of 1·1014 n/cm2. The presence of deep levels has been investigated by TSC and current-DLTS techniques