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arXiv · 1303.4631

Formation and stability of a two-dimensional nickel silicide on Ni (111) an Auger, LEED, STM, and high-resolution photoemission Study

B. Lalmi·C. Girardeaux·A. Portavoce·C. Ottaviani·B. Aufray·J. Bernardini
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Abstract

Using low energy electron diffraction (LEED), Auger electron spectroscopy (AES), scanning tunnelling microscopy (STM) and high resolution photo-electron spectroscopy (HR-PES) techniques we have studied the annealing effect of one silicon monolayer deposited at room temperature onto a Ni (111) substrate. The variations of the Si surface concentration, recorded by AES at 300°C and 400°C, show at the beginning a rapid Si decreasing followed by a slowing down up to a plateau equivalent to about 1/3 silicon monolayer. STM images and LEED patterns, both recorded at room temperature just after annealing, reveal the formation of an ordered hexagonal superstructure(rot3xrot3)R30°-type. From these observations and from a quantitative analysis of HR-PES data, recorded before and after annealing, we propose that the (rot3 x rot3)R30°superstructure corresponds to a two dimensional (2D) Ni2Si surface silicide.

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B. Lalmi, C. Girardeaux, A. Portavoce, C. Ottaviani, B. Aufray, J. Bernardini. 2013-03-19. Formation and stability of a two-dimensional nickel silicide on Ni (111) an Auger, LEED, STM, and high-resolution photoemission Study. https://arxiv.org/abs/1303.4631

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