MISORIENTATION EFFECT ON THE MONOLAYER TERRACE TOPOGRAPHY OF (100)INPSUBSTRATES ANNEALED UNDER A PH3 H-2 AMBIENT AND HOMOEPITAXIAL LAYERS GROWN BY METALORGANIC CHEMICAL-VAPOR-DEPOSITION/

The detailed monolayer terracelike topography of nominal on-axis and m isoriented vicinal (100) InP surfaces was systematically investigated by ''ex situ'' atomic force microscopy. Vicinal (100) InP reconstructs into steps around 550 degrees C in either argon or phosphine/hydrogen . Widths of observed monoatomic terraces are measured to be in close a greement with misorientation angles. Homoepitaxial growth by metalorga nic chemical vapor deposition preserves the terracelike structure. Gro wth acts through a monoatomic step flow mode following the classical B urton-Cabrera-Frank theory. Surface diffusion length is estimated up t o 350 nm in our standard growth conditions at 630 degrees C and 2.5 mu m/h. Spiral growth is also observed and takes its origin from a screw dislocation emerging on the surface of the substrate. The critical mi sorientation angle below which the spiral growth mechanism occurs and competes with the vicinal steps is in the range of 0.05 degrees-0.1 de grees. (C) 1995 American Institute of Physics.