INGAAS(P) INP MQW MIXING BY ZN DIFFUSION, GE AND S IMPLANTATION FOR OPTOELECTRONIC APPLICATIONS

There is a growing interest in impurity-induced layer disordering for the technologically important InGaAs(P)/InP system. More complicated than in the AlGaAs/GaAs ternary system, which concerns only interdiffusion of group III atoms, interdiffusion in this quaternary system can occur for both group III (Ga,In) and group V (P,As) atoms, which may or may not result in a strain-free alloy lattice-matched to InP, a major concern for device applications. After a brief review on the thermal stability of InP/InGaAs quantum well structures, we show that Zn diffusion at moderate temperature leads to intermixing on the group III sublattice, only, with subsequent lattice mismatch. On the other hand, either Ge or S implantation of InGaAs/InP quantum wells results in intermixing involving both the group III and the group V sublattice and approximating the lattice-matched condition.