Radiation-induced bistable centers with deep levels in silicon n +-p structures

The method of deep level transient spectroscopy is used to study electrically active defects in p-type silicon crystals irradiated with MeV electrons and alpha particles. A new radiation-induced defect with the properties of bistable centers is determined and studied. After keeping the irradiated samples at room temperature for a long time or after their short-time annealing at T similar to 370 K, this defect does not display any electrical activity in p-type silicon. However, as a result of the subsequent injection of minority charge carriers, this center transforms into the metastable configuration with deep levels located at E (V) + 0.45 and E (V) + 0.54 eV. The reverse transition to the main configuration occurs in the temperature range of 50-100A degrees C and is characterized by the activation energy similar to 1.25 eV and a frequency factor of similar to 5 x 10(15) s(-1). The determined defect is thermally stable at temperatures as high as T similar to 450 K. It is assumed that this defect can either be a complex of an intrinsic interstitial silicon atom with an interstitial carbon atom or a complex consisting of an intrinsic interstitial silicon atom with an interstitial boron atom.