NEUTRON-INDUCED DEFECTS IN SILICON DETECTORS CHARACTERIZED BY DLTS AND TSC METHODS

Neutron induced defects in silicon detectors fabricated from n-type fl oat zone material of different resistivity (100-6000 Omega cm) have be en studied using the C-DLTS (Capacitance-Deep Level Transient Spectros copy) and TSC (Thermally Stimulated Current) method. While the applica tion of the C-DLTS technique for high resistivity material is limited to neutron fluences below about 10(11) cm(-2) the TSC method remains a powerful tool for the defect characterization even at high fluences. Up to 5 defect levels were observed in some of the unirradiated sample s. These partly are due to thermal treatments during the fabrication p rocess. After neutron irradiation defect levels at E(c) -0.17, -0.23 a nd -0.42 eV and at E(v) + 0.36 eV were found. A detailed analysis of t he predominant peak at about -0.42 eV has shown that it is a superposi tion of two levels at -0.39 and -0.42 eV. For these defect levels intr oduction rates, annealing effects and a comparison between the DLTS an d TSC technique are presented. Possible correlations of these results with macroscopic detector properties are discussed.