During the molecular beam epitaxial growth of AlAs on the vicinal (100) surface of GaAs, reflection high-energy electron diffraction was used to measure the transition temperature between 2-dimensional nucleation and pure step propagation which occurred when sub-monolayer amounts of Sn were present on the surface. In the case of samples which were misoriented by 0.5º with respect to the [011] or [01¯1] direction, the transition temperature decreased by approximately 100C after the deposition of 0.6 of a monolayer of Sn. This indicated that the Ga mobility had increased.

G.S.Petrich, A.M.Dabiran, P.I.Cohen: Applied Physics Letters, 1992, 61[2], 162-4