Abstract:
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 $T\sim$ 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 50–100$^\circ$C and is characterized by the activation energy $\sim$1.25 eV and a frequency factor of $\sim$5 $\times$ 10$^{15}$ s$^{-1}$. The determined defect is thermally stable at temperatures as high as $T\sim$ 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.