skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Plasmon-enhanced electron scattering in nanostructured thin metal films revealed by low-voltage scanning electron microscopy

Abstract

The drastic enhancement of backscattered electrons (BSE) yield from nanostructured thin metal film which exceeded well the one from massive metal was observed at accelerating voltages below 400 V. The dependences of BSE signal from nanostructured gold film on accelerating voltage and on retarding grid potential applied to BSE detector were investigated. It was shown that enhanced BSE signal was formed by inelastic scattered electrons coming from the gaps between nanoparticles. A tentative explanation of the mechanism of BSE signal enhancement was suggested.

Authors:
 [1];  [2]; ;  [1]
  1. V.A. Fok Institute of Physics, St. Petersburg State University (Russian Federation)
  2. (Russian Federation)
Publication Date:
OSTI Identifier:
22609115
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1748; Journal Issue: 1; Conference: STRANN 2016: 5. international conference on state-of-the-art trends of scientific research of artificial and natural nanoobjects, St. Petersburg (Russian Federation), 26-29 Apr 2016; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; BACKSCATTERING; ELECTRIC POTENTIAL; ELECTRONS; FILMS; GOLD; NANOPARTICLES; NANOSTRUCTURES; PLASMONS; SCANNING ELECTRON MICROSCOPY; SCATTERING

Citation Formats

Mikhailovskii, V., E-mail: v.mikhailovskii@spbu.ru, IRC for Nanotechnology, Research Park, St.-Petersburg State University, Petrov, Yu., and Vyvenko, O. Plasmon-enhanced electron scattering in nanostructured thin metal films revealed by low-voltage scanning electron microscopy. United States: N. p., 2016. Web. doi:10.1063/1.4954339.
Mikhailovskii, V., E-mail: v.mikhailovskii@spbu.ru, IRC for Nanotechnology, Research Park, St.-Petersburg State University, Petrov, Yu., & Vyvenko, O. Plasmon-enhanced electron scattering in nanostructured thin metal films revealed by low-voltage scanning electron microscopy. United States. doi:10.1063/1.4954339.
Mikhailovskii, V., E-mail: v.mikhailovskii@spbu.ru, IRC for Nanotechnology, Research Park, St.-Petersburg State University, Petrov, Yu., and Vyvenko, O. Fri . "Plasmon-enhanced electron scattering in nanostructured thin metal films revealed by low-voltage scanning electron microscopy". United States. doi:10.1063/1.4954339.
@article{osti_22609115,
title = {Plasmon-enhanced electron scattering in nanostructured thin metal films revealed by low-voltage scanning electron microscopy},
author = {Mikhailovskii, V., E-mail: v.mikhailovskii@spbu.ru and IRC for Nanotechnology, Research Park, St.-Petersburg State University and Petrov, Yu. and Vyvenko, O.},
abstractNote = {The drastic enhancement of backscattered electrons (BSE) yield from nanostructured thin metal film which exceeded well the one from massive metal was observed at accelerating voltages below 400 V. The dependences of BSE signal from nanostructured gold film on accelerating voltage and on retarding grid potential applied to BSE detector were investigated. It was shown that enhanced BSE signal was formed by inelastic scattered electrons coming from the gaps between nanoparticles. A tentative explanation of the mechanism of BSE signal enhancement was suggested.},
doi = {10.1063/1.4954339},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1748,
place = {United States},
year = {Fri Jun 17 00:00:00 EDT 2016},
month = {Fri Jun 17 00:00:00 EDT 2016}
}
  • In this study silver, gold, palladium, and chromium films have been evaporated onto mica at substrate temperatures ranging from {minus}150C to +400C. Scanning tunneling microscopy (STM) images were obtained under ambient conditions. Silver and gold films exhibit an increasing grain size together with a grain flattening as the substrate temperature increases. At 275 and 400C for silver and gold, respectively, terraces with dimensions of the order of more than 100 nm are formed. However, also characteristic holes on the scale of a few 10 nm were always present. In addition, the gold films exhibit characteristic holes on the nanometer scale.more » While the larger holes are also visible on scanning electron microscopy micrographs, the small are not. Low-energy electron diffraction patterns prove the (111) orientation of both, silver and gold films; however, the quality of the silver patterns is better, consistent with the more perfect terraces as seen by STM. Palladium, evaporated at temperatures up to 350C did not exhibit similarly large and flat terraces. An improvement is achieved if prior to the palladium, silver is evaporated at elevated temperatures. Chromium, contrary to the fcc metals Ag, Au, and Pd crystallizes bcc, and forms a stable surface oxide under ambient conditions. The reproducibility of its STM images under ambient conditions depends on the applied bias and can be attributed to the surface oxide. Films evaporated at 50C exhibit a grainy structure. For the 350C films areas with columnar morphology have been observed. In conclusion, epitaxially grown Ag(111) films evaporated at 275C onto mica have been shown to exhibit large flat terraces suitable for nanoscale modifications and chemisorption studies with the STM.« less
  • Nanometal particles show characteristic features in chemical and physical properties depending on their sizes and shapes. For keeping and further enhancing their features, the particles should be protected from coalescence or degradation. One approach is to encapsulate the nanometal particles inside pores with chemically inert or functional materials, such as carbon, polymer, and metal oxides, which contain mesopores to allow permeation of only chemicals not the nanometal particles. Recently developed low-voltage high-resolution scanning electron microscopy was applied to the study of structural, chemical, and electron state of both nanometal particles and encapsulating materials in yolk-shell materials of Au@C, Ru/Pt@C, Au@TiO{submore » 2}, and Pt@Polymer. Progresses in the following categories were shown for the yolk-shell materials: (i) resolution of topographic image contrast by secondary electrons, of atomic-number contrast by back-scattered electrons, and of elemental mapping by X-ray energy dispersive spectroscopy; (ii) sample preparation for observing internal structures; and (iii) X-ray spectroscopy such as soft X-ray emission spectroscopy. Transmission electron microscopy was also used for characterization of Au@C.« less
  • We have studied the growth and structure of thin TiO{sub {ital x}} films on W(110) using Auger electron spectroscopy, low energy electron diffraction (LEED), and scanning tunneling microscopy (STM). The procedure used to grow these films includes the deposition of Ti metal onto the W(110) surface followed by a saturation oxygen exposure. LEED and STM reveal that several different ordered TiO{sub {ital x}} film structures can result depending upon the initial amount of Ti deposited and the final annealing temperature. Specifically, the oxidation and anneal to 1350 K of a one monolayer (ML) film of Ti resulted in the formationmore » of a strained ML structure that has a distorted hexagonal lattice and long-range order as observed by LEED and STM. The epitaxial relationship of this 1 ML TiO{sub {ital x}} structure with the W(110) substrate is found to occur with a Nishiyama{endash}Wassermann orientation. {copyright} {ital 1996 American Vacuum Society}« less
  • The surface topography of YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] thin films has been studied with both atomic force microscopy (AFM) and scanning tunneling microscopy (STM). The AFM images reveal a high density of small distinct nanoparticles, 10--50 nm across and 5--20 nm high, which do not appear in STM images of the same samples. In addition, we have shown that scanning the STM tip across the surface breaks off these particles and moves them to the edge of the scanned area, where they can later be imaged with the AFM.