Formation of single and double donor states of trivacancy-oxygen complexes in p-type silicon

摘要

Deep level transient spectroscopy (DLTS) has been applied to study the formation of trivacancy-oxygen complexes in Si. Samples of p-type Czochralski grown (Cz) silicon, with a boron doping concentration of ～1×10~(15) cm~(-3), have been irradiated at room temperature (RT) with 1.8 MeV protons to a dose of 5×10~(12) cm~(-2). Two new energy levels at E_v+0.24 eV and E_v+0.11 eV (E_v denotes the valence band edge) emerge when the divacancy (V_2) to divacancy-oxygen (V_2O) transition takes place during post-irradiation annealing. The concentration is ～30% relative to V_2 (or V_2O) and further, the two new levels exhibit an almost one-to-one correlation in strength. The present results strongly support that both levels are related to the same defect with a possible identification as single and double donor states of V_3O.