A detailed study was made of the structures of (001)-(2 x 4) surfaces by using ab initio pseudopotential calculations. The results indicated that the surface atomic geometries of the InAs(001)-β2(2 x 4) and GaAs(001)-β2(2 x 4) surfaces were very similar, and that the calculated geometrical results for InAs(001)-β2(2 x 4) agreed well with X-ray diffraction measurements. The equilibrium geometries of the equivalent surface atoms on the α(2 x 4), α2(2 x 4) and β2(2 x 4) reconstructions of InAs(001) were very similar. Simulation of the desorption of an As dimer from the β2(2 x 4) reconstruction indicated that the α2(2 x 4) reconstruction could easily take place at the InAs(001) surface, but not at the GaAs(001) surface. The calculations also suggested that, at 600 to 800K, the desorption rate of the As dimer from InAs(001)-β2(2 x 4) was approximately 10 times higher than that from GaAs(001)-β2(2 x 4).

Structure and Electronic States of InAs(001)-(2x4) Surfaces. R.H.Miwa, G.P.Srivastava: Physical Review B, 2000, 62[23], 15778-87