The surface reconstructions of indium grown onto Si(111) at coverages above one monolayer were studied by low-energy electron microscopy. Two-dimensional well-ordered In layers were prepared by deposition at room temperature onto the Si(111)-(√3 x √3)-R30° -In surface because room temperature growth of indium on clean Si(111)-(7 x 7) substrate was disordered. Three new surface reconstructions were observed when the thickness of the In layer increases from 1 to 2ML: (2 x 1); (1.5√3 x 1.5√3)-R30° and a mixture of (√7 x √3) and ‘(1 x 1)R30°’. On the double layer In grows at room temperature epitaxially in the form of three-dimensional crystals with predominant (100) orientation. The In(100) surface on top of these three-dimensional crystals was reconstructed in the same manner as found in an earlier low-energy electron diffraction study of the (100) surface of bulk In crystal. The preferred (100) orientation could be explained very well by the fact that the (√7 x √3) phase of the double layer had a centered square unit mesh that had a very small misfit with the centered unit mesh of the reconstructed In(100) surface. With increasing temperature the In(100) surface of the three-dimensional microcrystals deconstructs at ≈120C. At the same temperature the (√7 x √3) structure of the two-dimensional In layer underwent a reversible transition to a (1 x 1) pattern that was attributed to disordering of the In double layer. At low temperatures a third monolayer of In with a packing density of a slightly compressed In(111) plane grows on the double layer. Surface Reconstructions in Two and Three Dimensions - In on Si(111). A.Pavlovska, E.Bauer: Surface and Interface Analysis, 2005, 37[2], 110-4

2 x 1 Reconstruction of Si (111)