Epitaxial growth of a silicene sheet

Using atomic resolved scanning tunneling microscopy, we present here the experimental evidence of a silicene sheet (graphenelike structure) epitaxially grown on a close-packed silver surface [Ag(111)]. This has been achieved via direct condensation of a silicon atomic flux onto the single-crystal substrate in ultrahigh vacuum conditions. A highly ordered silicon structure, arranged within a honeycomb lattice, is synthesized and present two silicon sublattices occupying positions at different heights (0.02 nm) indicating possible sp(2)-sp(3) hybridizations

Formation de siliciures par réaction à l'état solide de films ultraminces de silicium sur des substrats métalliques (Si/Cu(001), Si/Ni(111)) - Etude structurale et cinétique

Ce travail porte sur l'étude des premiers stades de la formation des siliciures par réaction à l'état solide de dépôts ultraminces de silicium sur des substrats métalliques monocristallins (Cu(OO1), Ni(111)). Les deux systèmes modèles choisis (Si/Ni, Si/Cu) se caractérisent par une forte tendance à l'ordre, des solubilités limites importantes du Si dans le métal et une très forte tendance à la ségrégation superficielle du Si. Notre approche consiste à déposer deux sortes de films ultraminces de Si (~ 1 monocouche ou 5 monocouches) à température ambiante et ensuite à réaliser des expériences de dissolution (diffusion à l'état solide). A travers les cinétiques de dissolution, en couplant différentes techniques d'analyse de surface (AES, LEED, PES et STM) nous avons pu, d'une part, caractériser d'un point de vue cinétique et structural les composés 2D qui se forment lors de la dissolution d'une monocouche et, d'autre part, nous avons mis en évidence la formation séquentielle de deux composés 3D dans le cas de la dissolution de dépôts de l'ordre de 5 MC.AIX-MARSEILLE3-BU Sc.St Jérô (130552102) / SudocSudocFranceF

Atomic Transport in Nano-Crystalline Silicides Studied by <i>In Situ</i> Auger Electron Spectroscopy: Interfacial Reaction Effect

International audienc

Unusual Behaviour of the Dissolutions Kinetics of one Monolayer of Si in Cu(001)

International audienc

Silicene Structures On Silver Surfaces

In this paper we report on several structures of silicene, the analog of graphene for silicon, on the silver surfaces Ag(100), Ag(110) and Ag(111). Deposition of Si produces honeycomb structures on these surfaces. In particular, we present an extensive theoretical study of silicene on Ag(111) for which several recent experimental studies have been published. Different silicene structures were obtained only by varying the silicon coverage and/or its atomic arrangement. All the structures studied show that silicene is buckled, with a Si-Si nearest neighbor distance varying between 2.28 and 2.5. Due to the buckling in the silicene sheet, the apparent (lateral) Si-Si distance can be as low as 1.89. We also found that for a given coverage and symmetry, one may observe different scanning tunneling microscopy images corresponding to structures that differ by only a translation. © 2012 IOP Publishing Ltd

Theoretical and Experimental Evidences of Sequential Phase Formation during Sub-Nanometric-Thick Film Reactive Diffusion

International audienc

Adsorption of silicon on Au(110): An ordered two dimensional surface alloy

We report on experimental evidence for the formation of a two dimensional Si/Au(110) surface alloy. In this study, we have used a combination of scanning tunneling microscopy, low energy electron diffraction, Auger electron spectroscopy, and ab initio calculations based on density functional theory. A highly ordered and stable Si-Au surface alloy is observed subsequent to growth of a sub-monolayer of silicon on an Au(110) substrate kept above the eutectic temperature

Adsorption of silicon on Au(110): An ordered two dimensional surface alloy

We report on experimental evidence for the formation of a two dimensional Si/Au(110) surface alloy. In this study, we have used a combination of scanning tunneling microscopy, low energy electron diffraction, Auger electron spectroscopy, and ab initio calculations based on density functional theory. A highly ordered and stable Si-Au surface alloy is observed subsequent to growth of a sub-monolayer of silicon on an Au(110) substrate kept above the eutectic temperature. (C) 2012 American Institute of Physics. http://dx.doi.org/10.1063/1.4735310