Use of platinum for lifetime control in power devices

The diffusion of Pt into Si at temperatures between 800 and 1000°C has been found to provide room-temperature minority-carrier lifetimes between 1 µsec and 10 nsec. Evaluation of the dependence of lifetime on ambient temperature and on majority carrier doping as well as the measurement of thermally stimulated currents indicate the presence of two recombination centers: an acceptor located 0.26 eV below the conduction band edge for n-type Si and a donor located 0.32 eV above the valence band edge for p-type Si.