INFLUENCE OF MONOMOLECULAR STEPS ON THE 1ST-ORDER STRUCTURE TRANSITION OF AN INAS(001) SURFACE

The surface stoichiometry transition from As-covered 2x4 to In-covered 4x2 on InAs(001) misoriented surface is studied by reflection high-energy electron diffraction. The width of the hysteresis due to the first-order phase transition between these two structures is smaller with a surface misoriented toward the [110BAR] direction than that with an exactly oriented surface. The results from Monte Carlo simulation indicate that this phenomenon can be explained by the finite size effect on the first-order surface stoichiometry transition caused by the existence of monomolecular steps.