Kinetics of thermal donor generation in silicon

Abstract

The generation kinetics of thermal donors at 450 °C in Czochralski-grown silicon was found to be altered by high-temperature preannealing (e.g., 1100 °C for 30 min). Thus, when compared with as-grown Si, high-temperature preannealed material exhibits a smaller concentration of generated thermal donors and a faster thermal donor saturation. A unified mechanism of nucleation and oxygen diffusion-controlled growth (based on solid-state phase transformation theory) is proposed to account for generation kinetics of thermal donors at 450 °C, in as-grown and high-temperature preannealed Czochralski silicon crystals. This mechanism is consistent with the main features of the models which have been proposed to explain the formation of oxygen thermal donors in silicon.