Disordering of Si-Doped AlAs/GaAs Superlattice by Annealing

Abstract

Effect of Si-doping levels and annealing temperature on disordering of 150-Å AlAs/150-Å GaAs superlattices is studied. The doping level of 4×10 18 cm -3 cause disorder for 800°C, 2 h annealing, while the doping level of 1×10 18 cm -3 does not induce disorder on this annealing condition. A superlattice which is doped with 1×10 19 Si cm -3 disintegrates after 650°C, 2 h annealing and the diffusion coefficient of Al–Ga interdiffusion is estimated to be 3×10 -17 cm 2 s -1 . For 800°C, 2 h annealing the two undoped AlAs/GaAs layers adjacent to the doped region are disordered by Si diffusion.