Effect of Oxygen on the Stability of Ag islands on Si(111)-(7x7)

ORAL

Abstract

We are working to determine whether an electronic effect known as the quantum size effect can influence chemisorption on Ag islands of different height. We have used scanning tunneling microscopy to probe the effect of oxygen exposure on an ensemble of Ag islands separated by a Ag wetting layer on Si(111)-(7x7). Starting from a distribution dominated by islands that are 1 layer high (measured with respect to the wetting layer), coarsening in ultrahigh vacuum at room temperature leads to growth of 2-layer islands at the expense of 1-layer islands, which is expected. If, however, the sample is exposed to oxygen, coarsening leads to growth of 3-layer islands. There is no evidence for oxygen adsorption on top of Ag islands, but there is clear evidence for adsorption in the wetting layer. Density functional theory supports a model in which traces of oxygen on top of Ag islands can change the height-dependent relative stabilities of the islands. Dahai Shao, et al. Surf. Sci. 606, 1871 (2012).

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Authors

  • Dahai Shao

    Ames Laboratory. Department of Chemistry, Iowa State University

  • Jatinder Kumar

    Harvard U., Baker University, Bejing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Northrop Grumman, Baltimore, MD, University of Kansas Dept. of Physics \& Astronomy, Kansas State University, Department of Chemistry, College of Materials Science \& Engineering, Sichuan University, China, Illinois State University, Mullard Space Science Laboratory, University College of London, Holmbury St. Mary, United Kingdom, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States, Weizmann Institute of Science, Rehovot, Israel, Monmouth College, Missouri State University, Birla Institute of Technology and Science, University of Illinois at Urbana Champaign, Ames Laboratory. Department of Physics and Astronomy, Iowa State University, Siena College, \'Ecole Polytechnique F\'ed\'erale de Lausanne, Switzerland, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Kansas State University, Purdue University, Princeton University, Oklahoma State University, University of Chicago, University of Iowa, University of Kansas, University of Kansas and University of Iowa

  • Jatinder Kumar

    Harvard U., Baker University, Bejing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Northrop Grumman, Baltimore, MD, University of Kansas Dept. of Physics \& Astronomy, Kansas State University, Department of Chemistry, College of Materials Science \& Engineering, Sichuan University, China, Illinois State University, Mullard Space Science Laboratory, University College of London, Holmbury St. Mary, United Kingdom, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States, Weizmann Institute of Science, Rehovot, Israel, Monmouth College, Missouri State University, Birla Institute of Technology and Science, University of Illinois at Urbana Champaign, Ames Laboratory. Department of Physics and Astronomy, Iowa State University, Siena College, \'Ecole Polytechnique F\'ed\'erale de Lausanne, Switzerland, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Kansas State University, Purdue University, Princeton University, Oklahoma State University, University of Chicago, University of Iowa, University of Kansas, University of Kansas and University of Iowa

  • Jatinder Kumar

    Harvard U., Baker University, Bejing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Northrop Grumman, Baltimore, MD, University of Kansas Dept. of Physics \& Astronomy, Kansas State University, Department of Chemistry, College of Materials Science \& Engineering, Sichuan University, China, Illinois State University, Mullard Space Science Laboratory, University College of London, Holmbury St. Mary, United Kingdom, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States, Weizmann Institute of Science, Rehovot, Israel, Monmouth College, Missouri State University, Birla Institute of Technology and Science, University of Illinois at Urbana Champaign, Ames Laboratory. Department of Physics and Astronomy, Iowa State University, Siena College, \'Ecole Polytechnique F\'ed\'erale de Lausanne, Switzerland, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Kansas State University, Purdue University, Princeton University, Oklahoma State University, University of Chicago, University of Iowa, University of Kansas, University of Kansas and University of Iowa

  • Jatinder Kumar

    Harvard U., Baker University, Bejing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Northrop Grumman, Baltimore, MD, University of Kansas Dept. of Physics \& Astronomy, Kansas State University, Department of Chemistry, College of Materials Science \& Engineering, Sichuan University, China, Illinois State University, Mullard Space Science Laboratory, University College of London, Holmbury St. Mary, United Kingdom, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States, Weizmann Institute of Science, Rehovot, Israel, Monmouth College, Missouri State University, Birla Institute of Technology and Science, University of Illinois at Urbana Champaign, Ames Laboratory. Department of Physics and Astronomy, Iowa State University, Siena College, \'Ecole Polytechnique F\'ed\'erale de Lausanne, Switzerland, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Kansas State University, Purdue University, Princeton University, Oklahoma State University, University of Chicago, University of Iowa, University of Kansas, University of Kansas and University of Iowa

  • Jatinder Kumar

    Harvard U., Baker University, Bejing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Northrop Grumman, Baltimore, MD, University of Kansas Dept. of Physics \& Astronomy, Kansas State University, Department of Chemistry, College of Materials Science \& Engineering, Sichuan University, China, Illinois State University, Mullard Space Science Laboratory, University College of London, Holmbury St. Mary, United Kingdom, Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, United States, Weizmann Institute of Science, Rehovot, Israel, Monmouth College, Missouri State University, Birla Institute of Technology and Science, University of Illinois at Urbana Champaign, Ames Laboratory. Department of Physics and Astronomy, Iowa State University, Siena College, \'Ecole Polytechnique F\'ed\'erale de Lausanne, Switzerland, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Kansas State University, Purdue University, Princeton University, Oklahoma State University, University of Chicago, University of Iowa, University of Kansas, University of Kansas and University of Iowa

  • Patricia Thiel

    Ames Laboratory. Department of Chemistry, and Department of Materials Science and Engineering, Iowa State University