Influence of heat treatment of silicon on minority carrier lifetime

The influence of annealing on the lifetime of minority carriers has been investigated in a temperature range from 600 °C to 1200 °C. The annealing introduces the recombiation and trapping centres into Si. The process of recombination can be explained on a two-level model where one level acts as a recombination one and the other acts either as a recombination or as a trapping level, depending on the Fermi level position. The ways of preventing the diffusion of impurities from the surface into Si material were sought because this diffusion is the main cause of variations of due to annealing.