Influence of oxygen on surface reconstruction and growth of (001) vanadium

In this paper, the role of oxygen on surface reconstruction and growth of ( 0 0 1) vanadium is investigated. By using electron diffraction, in-plane la ttice spacing oscillations are observed during the layer by layer vanadium growth. The amplitude of these oscillations which are due to elastic relaxa tion at the edges of the two-dimensional (2D) growing islands, are sometime s very large and thus cannot be explained by size effect in homo-epitaxy. W e observe that the oscillation amplitude is clearly correlated with the pre sence of oxygen on the initial surface, as checked by Auger spectroscopy. A s the presence of oxygen induces surface reconstructions, the electron diff raction experiments also allow us to demonstrate that these superstructures are compressed compared to an oxygen free 1 x 1 V surface. The peculiar mo rphology of these surface reconstructions, investigated by scanning tunnell ing microscopy, may be explained by this compressive strain. (C) 2001 Elsev ier Science B.V. All rights reserved.