Co-implantation of Al+, P+, and S+ with Si+ implants into In0.53Ga0.47As

Abstract

Elevated temperature, nonamorphizing implants of Si+, and a second co-implant of either Al+, P+, or S+ at varying doses were performed into In0.53Ga0.47As to observe the effect that individual co-implant species had on the activation and diffusion of Si doping after postimplantation annealing. It was found that Al, P, and S co-implantation all resulted in a common activation limit of 1.7 × 1019 cm−3 for annealing treatments that resulted in Si profile motion. This is the same activation level observed for Si+ implants alone. The results of this work indicate that co-implantation of group V or VI species is an ineffective means for increasing donor activation of n-type dopants above 1.7 × 1019 cm−3 in InGaAs. The S+ co-implants did not show an additive effect in the total doping despite exhibiting significant activation when implanted alone. The observed n-type active carrier concentration limits appear to be the result of a crystalline thermodynamic limit rather than dopant specific limits.