Annealing experiments were performed on undoped single-well heterostructures which had been grown by means of molecular beam epitaxy. The annealing was carried out in evacuated and sealed silica ampoules. The annealing temperature and time were 1000C and 4h, respectively, while the As vapor pressure in the ampoules was varied from the dissociation pressure to about 108kPa. Compositional profiles were obtained by using dynamic secondary ion mass spectrometry. It was found that the amount of intermixing in the layers depended upon both the As pressure and the distance from the sample surface. In contrast with previous studies, the complex variation in interdiffusion as a function of As pressure which was observed here could not be explained in terms of interdiffusion via group-III vacancies and interstitials alone.

Arsenic Pressure Dependence of Group III Atom Interdiffusion in GaAs-AlAs Single-Well Heterostructures. N.Baba-Ali, I.Harrison, B.Tuck: Journal of Materials Science - Materials in Electronics, 1995, 6[3], 127-34