K. Mahalingam et al., A MONTE-CARLO STUDY OF GALLIUM DESORPTION-KINETICS DURING MBE OF (100)-GAAS ALGAAS HETEROSTRUCTURES/, Journal of crystal growth, 175, 1997, pp. 211-215
In situ desorption mass spectrometry studies (DMS) of AlGaAs/GaAs mole
cular beam epitaxy (MBE) at high substrate temperatures reveals a rich
transient behavior in the Ga desorption signal during the formation o
f the AlGaAs-on-GaAs interface. In this study we develop Monte Carlo (
MC) models for Ga desorption, in which the effects of the Al-Ga intera
ction strength and the inclusion of an Al-Ga surface exchange mechanis
m are investigated. The models which best describe the experimental ob
servations are identified. The transients in Ga desorption rate at the
AlGaAs-on-GaAs interface and the experimentally observed reduction in
Ga desorption energy during growth of AlGaAs are explained in terms o
f the reduction in V/III flux ratio accompanying the opening of the Al
shutter. The proposed effects of this reduction in V/III flux ratio a
re consistent with the results predicted by the different models.