Interfacial structure and morphology of nano-crystalline Ag on Si(111)7x7: an in-situ x-ray scattering study

POSTER

Abstract

There is intense interest to understand the factors that control the growth of nano-scale metals on supported substrates and, although the Ag/Si(111) system has been extensively studied for this purpose, little is known about the buried interface of the Ag nano-islands because most experimental probes only detect the top surface. Here, we present the results of in situ synchrotron x-ray scattering studies that reveal previously unknown and unexpected features of the buried nano-island/substrate interface. It is found that the incommensurate FCC Ag nano-islands consume the wetting layer upon which they grow and the islands extend to the reconstructed 7x7 Si surface. Consequently, the Ag island height distribution is one monolayer thicker than previously assumed, with a trilayer being the most stable island height at low coverage. Moreover, the lattice spacing of the islands is determined to be the same as bulk Ag, contrary to several prior STM measurements. These results are discussed in terms of the competition between electron confinement effects versus the role of interfacial energy, both of which are important for determining the growth morphology of nano-scale metals on supported substrates.

Authors

  • Yiyao Chen

    University of Missouri

  • Mark Neubauer

    University of Missouri-Columbia, Southern Illinois University Carbondale, Indiana University, Purdue University, Argonne National Laboratory, University of Missouri, College of Physics Science, Qingda University, Qingdao, 266071, China, Indian Institute of Science, Bangalore, India, University of Massachusetts Amherst, Iowa State University, Technical University of Denmark, University of Missouri - Columbia, University of California - San Diego, La Jolla, CA 92093, Department of Physics, University of Missouri-Columbia, Columbia, Missouri 65211, Department of Physics and Astronomy, University of Missouri-Columbia, University of Missouri, Columbia, MO, Department of Physics and Department of Biochemistry, University of Missouri, Columbia, MO 65211, Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, Univ of Missouri - Columbia, Duke University, Shanghai Jiaotong University, Ames Laboratory, U.S. DOE, Texas Center of Superconductivity and the Department of Physics, University of Houston, Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 66036, Russia, Oak Ridge National Laboratory, NIST Center for Neutron Research, MU Research Reactor, Ames Laboratory and Dep. of Physics and Astronomy, Iowa State University, AmesAmes Laboratory and Dep. of Physics and Astronomy, Iowa State University, HFIR, Oak Ridge National Laboratory, University of Illinois at Urbana-Champaign

  • Mark Neubauer

    University of Missouri-Columbia, Southern Illinois University Carbondale, Indiana University, Purdue University, Argonne National Laboratory, University of Missouri, College of Physics Science, Qingda University, Qingdao, 266071, China, Indian Institute of Science, Bangalore, India, University of Massachusetts Amherst, Iowa State University, Technical University of Denmark, University of Missouri - Columbia, University of California - San Diego, La Jolla, CA 92093, Department of Physics, University of Missouri-Columbia, Columbia, Missouri 65211, Department of Physics and Astronomy, University of Missouri-Columbia, University of Missouri, Columbia, MO, Department of Physics and Department of Biochemistry, University of Missouri, Columbia, MO 65211, Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, Univ of Missouri - Columbia, Duke University, Shanghai Jiaotong University, Ames Laboratory, U.S. DOE, Texas Center of Superconductivity and the Department of Physics, University of Houston, Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 66036, Russia, Oak Ridge National Laboratory, NIST Center for Neutron Research, MU Research Reactor, Ames Laboratory and Dep. of Physics and Astronomy, Iowa State University, AmesAmes Laboratory and Dep. of Physics and Astronomy, Iowa State University, HFIR, Oak Ridge National Laboratory, University of Illinois at Urbana-Champaign

  • Mark Neubauer

    University of Missouri-Columbia, Southern Illinois University Carbondale, Indiana University, Purdue University, Argonne National Laboratory, University of Missouri, College of Physics Science, Qingda University, Qingdao, 266071, China, Indian Institute of Science, Bangalore, India, University of Massachusetts Amherst, Iowa State University, Technical University of Denmark, University of Missouri - Columbia, University of California - San Diego, La Jolla, CA 92093, Department of Physics, University of Missouri-Columbia, Columbia, Missouri 65211, Department of Physics and Astronomy, University of Missouri-Columbia, University of Missouri, Columbia, MO, Department of Physics and Department of Biochemistry, University of Missouri, Columbia, MO 65211, Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, Univ of Missouri - Columbia, Duke University, Shanghai Jiaotong University, Ames Laboratory, U.S. DOE, Texas Center of Superconductivity and the Department of Physics, University of Houston, Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 66036, Russia, Oak Ridge National Laboratory, NIST Center for Neutron Research, MU Research Reactor, Ames Laboratory and Dep. of Physics and Astronomy, Iowa State University, AmesAmes Laboratory and Dep. of Physics and Astronomy, Iowa State University, HFIR, Oak Ridge National Laboratory, University of Illinois at Urbana-Champaign

  • Mark Neubauer

    University of Missouri-Columbia, Southern Illinois University Carbondale, Indiana University, Purdue University, Argonne National Laboratory, University of Missouri, College of Physics Science, Qingda University, Qingdao, 266071, China, Indian Institute of Science, Bangalore, India, University of Massachusetts Amherst, Iowa State University, Technical University of Denmark, University of Missouri - Columbia, University of California - San Diego, La Jolla, CA 92093, Department of Physics, University of Missouri-Columbia, Columbia, Missouri 65211, Department of Physics and Astronomy, University of Missouri-Columbia, University of Missouri, Columbia, MO, Department of Physics and Department of Biochemistry, University of Missouri, Columbia, MO 65211, Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290, Univ of Missouri - Columbia, Duke University, Shanghai Jiaotong University, Ames Laboratory, U.S. DOE, Texas Center of Superconductivity and the Department of Physics, University of Houston, Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, 66036, Russia, Oak Ridge National Laboratory, NIST Center for Neutron Research, MU Research Reactor, Ames Laboratory and Dep. of Physics and Astronomy, Iowa State University, AmesAmes Laboratory and Dep. of Physics and Astronomy, Iowa State University, HFIR, Oak Ridge National Laboratory, University of Illinois at Urbana-Champaign