Theoretical study of Si(001)/Te - (1×1), (2×1) and (3×1) surfaces

• Autor(a) principal: Miwa,R. H.
• Data de Publicação: 1999
• Outros Autores: Ferraz,A. C.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Physics
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97331999000400043

The atomic geometry, chemical bonding and energetics for full -, 2/3, 1/2 and 1/3 of a monolayer of Te coverages on the Si(001)/Te -(1 x 1), (2 x 1), and (3 x 1) surfaces have been studied employing first - principles total-energy calculations. For one monolayer coverage we nd that the (1 x 1) structure is energetically favourable against (2 x 1) structure, in agreement with experimental results, indicating that the dimerization of Te atoms is not an exothermic process. For a coverage of 2/3 of a monolayer, the formation of Te-Si-Te mixed trimers, in a (3 x 1) - reconstruction, is an energetically stable configuration. At 1/3 coverage, we have obtained the formation of Si-Si dimers with a single Te atom, at the surface in a (3 x 1) - reconstruction. In this structure there is a very weak interaction between the dimer and the single Te atom.