A strained single quantum well of GaAs/Ga0.77In0.23Ga/GaAs was grown, via low-pressure metal-organic vapor phase epitaxy, onto a (100)GaAs substrate at 625C. Samples were annealed under AsH3/H2 at temperatures ranging from 750 to 900C. Since the quantum well thickness of about 8nm was below the critical value for this lattice-mismatched system, it was assumed that the GaInAs layer was commensurate with the GaAs substrate. The low-temperature (2K) photoluminescence of the electron to heavy hole transition in the quantum well of these samples was analyzed in order to study In/Ga interdiffusion at the GaInAs/GaAs interfaces. The energies of the photoluminescence peaks shifted to higher values during annealing. These shifts were quantitatively interpreted in terms of changes in the quantum well profile, due to In and Ga interdiffusion. The interdiffusion coefficient at 850C was deduced to be 3 x 10-17cm2/s; with an activation energy of 2.07eV. The values which were obtained for the In/Ga interdiffusion coefficient were larger than the published values for Al and Ga interdiffusion in AlGaAs/GaAs heterojunctions.

F.Iikawa, P.Motisuke, J.A.Brum, M.A.Sacilotti, A.P.Roth, R.A.Masut: Journal of Crystal Growth, 1988, 93, 336-41