X-Ray diffraction studies of the InSb(001) surface

The (001) surface of the III-V alloy semiconductors exhibits many reconstructions with large unit meshes. The appearance of a given reconstruction depends on the processing conditions and, in particular on the stoichiometry at the surface. A surface X-ray diffraction study of the atomic structure of the Sb-rich c(4 x 4) and the In-rich c(8 x 2) surfaces is described which allows for the first time, a detailed atomic model of these important reconstructions to be derived. The basic units consist of groups of Sb dimers and rows of In atoms on top of an Sb terminated bulk. The local bonding is similar to that found in rhombahedral Sb and tetragonal In bulk structures. The results explain why the Sb rich surface is used as a starting point for the growth and are relevant to other III-V (001) surfaces. (author)