Diffusion of P- and N-Type Dopants in GaAs/AIGaAs DH Structure Grown by MOCVD

Most of AIGaAs laser diodes (LDs) contain the doublehetero (DH) structure. The DH structure consists of AIGaAs layers with high Al composition as cladding layers and undoped GaAs or AIGaAs with low Al composition. Therefore, it is important for improvement of device characteristics to understand and control the diffusion of dopants. However, most work on the diffusion of dopants have been carried out on the diffusion in GaAs. In this paper, we compared electrical and optical properties of Si-doped AIGaAs with those of Se-doped AIGaAs and investigated the diffusion of Si, Se and Zn in the GaAs/Al0.48Ga0.52As DH structure by secondary ion mass spectroscopy (SIMS). Doping profile of Si is controllable rather than that of Se. However, from the viewpoint of device characteristics, Se is more suitable than Si.