Scanning tunnelling microscopy was used to study the interaction of elemental B with Si(111)-(7 x 7) surface. Elemental B was evaporated at desired temperature (room temperature, 800 to 1000C), and the amount of B was varied with the evaporation time. The shapes and structures of the reconstructed areas were only dependent on B coverages. The reconstructed areas which mostly consisted of the two types of ring structures (bright ring and dark ring) were formed in very small B coverage. When larger amount of B was evaporated, the reconstructed areas containing a mixture of various adatom structures such as (√3 x √3)R30°, 2 x 2, c(4 x 2) and the 2 types of ring structures were formed. These areas grow larger over the surface in proportion to the amount of B until overall of the surface changes to these areas. When much more B was evaporated, the number of the (√3 x √3)R30° unit cells increases in these reconstructed surface and well-ordered (√3 x √3)R30° surface was formed finally.

Initial Stage of Si(111)-B Surface Reconstruction Studied by Scanning Tunnelling Microscopy. T.Yamamoto, S.Ohara, K.Ezoe, H.Kuriyama, K.Ishii, S.Matsumoto: Applied Surface Science, 1998, 130-132, 1-5