Surface reactions of As and Ga on Sb-terminated GaAs(001) were investi
gated by reflection high energy electron diffraction and photoelectron
spectroscopy to examine the stability of an Sb terminating layer as a
pseudomorphic GaSb layer formed on GaAs(001) for fabricating GaAs/GaS
b/GaAs single quantum wells. In the As reaction, As atoms react with t
he Sb atoms and induce the breaking of Ga-Sb bonds. On the other hand,
when Ga atoms are deposited, Ga atoms migrate on the Sb-terminated su
rface and the Sb layer is conserved even when the substrate is anneale
d until Sb atoms desorb. These features indicate that controlling As d
eposition on the Sb layer plays a key role in preventing intermixing b
etween GaSb and a GaAs overlayer for fabricating the abrupt interface
of GaAs/GaSb/GaAs single quantum well structures.