Transition metal impurities in silicon: New defect reactions

Recent investigations on transition-metal impurities in silicon emphasizing the effect of the combined diffusion of two transition metals are presented and briefly discussed. The electronic properties and basic thermal kinetics are analysed by DLTS. The conversion of a Pd-related multivalent defect atE_c-0.35 eV andE_c-0.57 eV to the Pd-related defect atE_c –0.22 eV is observed, and a Pd-Fe complex level atE_c –0.32 eV is identified. The annealing characteristics of the multivalent Rh levels atE_c-0.33 eV andE_c-0.57 eV are observed, and used to analyse the influence of prior Rh doping on the Au diffusion. A complex formed by the codiffusion of Au and Cu is observed atE_v+0.32eV andE_v+0.42 eV, and shown to exhibit bistable behavior as does a similarly produced Au-Ni complex observed atE_v + 0.35 eV andE_v+0.48 eV.