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

Title: Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber

Abstract

Abstract A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope’s objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens andin situchemical and electrochemical processes.

Authors:
ORCiD logo; ; ;
Publication Date:
Research Org.:
Energy Frontier Research Centers (EFRC) (United States). Energy Materials Center at Cornell (EMC2)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1370449
DOE Contract Number:  
SC0001086
Resource Type:
Journal Article
Journal Name:
Microscopy and Microanalysis
Additional Journal Information:
Journal Volume: 22; Journal Issue: 04; Related Information: Emc2 partners with Cornell University (lead); Lawrence Berkeley National Laboratory; Journal ID: ISSN 1431-9276
Publisher:
Microscopy Society of America (MSA)
Country of Publication:
United States
Language:
English

Citation Formats

Nguyen, Kayla X., Holtz, Megan E., Richmond-Decker, Justin, and Muller, David A. Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber. United States: N. p., 2016. Web. doi:10.1017/s1431927616011405.
Nguyen, Kayla X., Holtz, Megan E., Richmond-Decker, Justin, & Muller, David A. Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber. United States. doi:10.1017/s1431927616011405.
Nguyen, Kayla X., Holtz, Megan E., Richmond-Decker, Justin, and Muller, David A. Mon . "Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber". United States. doi:10.1017/s1431927616011405.
@article{osti_1370449,
title = {Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber},
author = {Nguyen, Kayla X. and Holtz, Megan E. and Richmond-Decker, Justin and Muller, David A.},
abstractNote = {Abstract A long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope’s objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens andin situchemical and electrochemical processes.},
doi = {10.1017/s1431927616011405},
journal = {Microscopy and Microanalysis},
issn = {1431-9276},
number = 04,
volume = 22,
place = {United States},
year = {2016},
month = {7}
}

Works referenced in this record:

Electron microscopy of specimens in liquid
journal, October 2011

  • de Jonge, Niels; Ross, Frances M.
  • Nature Nanotechnology, Vol. 6, Issue 11, p. 695-704
  • DOI: 10.1038/nnano.2011.161