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Title: Growth and structural evolution of Sn on Ag(001): Epitaxial monolayer to thick alloy film

Abstract

The growth and structure of Sn on Ag(001), from submonolayer to thick film coverages at room temperature, are studied using low energy electron diffraction, x-ray photoemission spectroscopy and angle-resolved photoemission spectroscopy (ARPES) techniques. The authors observe different growth modes for submonolayer Sn coverages and for higher Sn coverages. Systematic surface structural evolution, consistent with the substitution of surface Ag atoms by Sn atoms, is observed for submonolayer Sn coverages while an ordered Ag-Sn bulk alloy film is formed for higher Sn coverages with an Ag overlayer. For monolayer coverage of Sn, a pseudomorphic growth of a Sn layer without alloying is determined. ARPES results also confirm the presence of an ordered Ag overlayer on the bulk Ag-Sn alloy film, suggesting the formation of an Ag/Ag{sub 3}Sn/Ag(001) sandwich structure at the surface for higher Sn coverages. The present results illustrate the complex interplay of atomic mobilities, surface free-energies, and alloy formation energies in determining the growth and structural properties of the system.

Authors:
 [1];  [2]
  1. Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India and Department of Applied Sciences, Haldia Institute of Technology, Haldia, 721657 Purba Medinipur, West Bengal (India)
  2. Surface Physics and Material Science Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)
Publication Date:
OSTI Identifier:
22592879
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 4; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRON DIFFRACTION; EPITAXY; FILMS; FORMATION HEAT; FREE ENERGY; LAYERS; PHOTOELECTRON SPECTROSCOPY; PHOTOEMISSION; SILVER ALLOYS; SURFACES; TEMPERATURE RANGE 0273-0400 K; TIN ALLOYS; X-RAY DIFFRACTION

Citation Formats

Chakraborty, Suvankar, and Menon, Krishnakumar S. R., E-mail: krishna.menon@saha.ac.in. Growth and structural evolution of Sn on Ag(001): Epitaxial monolayer to thick alloy film. United States: N. p., 2016. Web. doi:10.1116/1.4953543.
Chakraborty, Suvankar, & Menon, Krishnakumar S. R., E-mail: krishna.menon@saha.ac.in. Growth and structural evolution of Sn on Ag(001): Epitaxial monolayer to thick alloy film. United States. doi:10.1116/1.4953543.
Chakraborty, Suvankar, and Menon, Krishnakumar S. R., E-mail: krishna.menon@saha.ac.in. 2016. "Growth and structural evolution of Sn on Ag(001): Epitaxial monolayer to thick alloy film". United States. doi:10.1116/1.4953543.
@article{osti_22592879,
title = {Growth and structural evolution of Sn on Ag(001): Epitaxial monolayer to thick alloy film},
author = {Chakraborty, Suvankar and Menon, Krishnakumar S. R., E-mail: krishna.menon@saha.ac.in},
abstractNote = {The growth and structure of Sn on Ag(001), from submonolayer to thick film coverages at room temperature, are studied using low energy electron diffraction, x-ray photoemission spectroscopy and angle-resolved photoemission spectroscopy (ARPES) techniques. The authors observe different growth modes for submonolayer Sn coverages and for higher Sn coverages. Systematic surface structural evolution, consistent with the substitution of surface Ag atoms by Sn atoms, is observed for submonolayer Sn coverages while an ordered Ag-Sn bulk alloy film is formed for higher Sn coverages with an Ag overlayer. For monolayer coverage of Sn, a pseudomorphic growth of a Sn layer without alloying is determined. ARPES results also confirm the presence of an ordered Ag overlayer on the bulk Ag-Sn alloy film, suggesting the formation of an Ag/Ag{sub 3}Sn/Ag(001) sandwich structure at the surface for higher Sn coverages. The present results illustrate the complex interplay of atomic mobilities, surface free-energies, and alloy formation energies in determining the growth and structural properties of the system.},
doi = {10.1116/1.4953543},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 4,
volume = 34,
place = {United States},
year = 2016,
month = 7
}
  • The structural and magnetic properties of a series of Co{sub 2}FeAl Heusler alloy films grown on GaAs(001) substrate by molecular beam epitaxy have been studied. The epitaxial Co{sub 2}FeAl films with an ordered L{sub 21} structure have been successfully obtained at growth temperature of 433 K, with an in-plane cubic magnetic anisotropy superimposed with an unusual uniaxial magnetic anisotropy. With increasing growth temperature, the ordered L{sub 21} structure degrades. Meanwhile, the uniaxial anisotropy decreases and eventually disappears above 673 K. The interfacial bonding between As and Co or Fe atom is suggested to be responsible for the additional uniaxial anisotropy.
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