O2 adsorption on Si(111)-c(2x8)


  • Contact Researcher: , Dr.
  • Hosted LIMMS Japanese Laboratory: [http:// Prof] --- Micro Components and Systems

Project Overview

  • Keywords

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  • Objectives :
  • Methods :The adsorption of molecular oxygen on the c(2x8) reconstruction of quenched Si(111) surfaces has been studied at the atomic scale using scanning tunneling microscopy (STM) at room temperature (RT). It has been found that clean well reconstructed c(2 x8) adatoms do not react with O2 molecules but that a limited oxidation can start where adatom sites arranged in sqr3xsqr3 reconstructed structures are present. Comparison between O2 adsorption on Si(111)-c(2x 8) and Si(111)-7x7 reconstructions coexisting on the same quenched silicon surface has been carried out in detail. For each atomic site present on the surface the variation of reacted sites with exposure has been measured. For low O2 exposures, bright and dark oxygen induced sites appear on the Si(111)-7x 7, while Si(111)-c(2x8) does not oxidized at all. At high O2 exposures, large oxidation areas have spread on the 7x7 reconstruction, preferentially on the faulted halves of the unit cell, and smaller oxidation areas induced by topological defects have grown all around clean un-reacted c(2x 8) regions.

Report(s) and Publication(s)

  • References :
F.Rose, S.Kawai,and H.Kawakatsu, Low reactivity of molecular oxygen with Si(111)-c(2x8), Surface Science 600, p. 106 (2006).