Defect energy levels in boron-doped silicon irradiated with 1-MeV electrons

Using transient capacitance spectroscopy, we studied defect energy levels and their annealing behavior in boron-doped silicon of various resistivities irradiated with 1-MeV electrons at room temperature. Three levels located at $E_v+0.23\mathrm{}$, $E_v+0.38\mathrm{}$, and $E_c-0.27\mathrm{}$ eV consistently appear in various samples, showing they are characteristic defects in boron-doped silicon. Many properties of the $E_v+0.23\mathrm{}$-eV level and the divacancy are the same, according to the present study and others. We correlated the $E_v+0.38\mathrm{}$-eV level to the vacancy-oxygen-carbon complex recently identified by Lee and Corbett using the EPR technique. The $E_c-0.27\mathrm{}$-eV level could arise from an interstitial defect of oxygen and boron; and a new level at $E_v+0.30\mathrm{}$ eV arising upon its disappearance could be a vacancy defect trapping an oxygen atom and a boron. Several additional defect levels are reported.