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

  • Kayla X. Nguyen (a1), Megan E. Holtz (a1), Justin Richmond-Decker (a1) and David A. Muller (a1) (a2)
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 400 μm, 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 and in situ chemical and electrochemical processes.

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* Corresponding author. kn324@cornell.edu
References
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AbramsI.M. & McBainJ.W. (1944). A closed cell for electron microscopy. Science 100, 273274.
BotheW. (1921 a). Theory of the diffusion of alpha-rays on small angles. Z Phys 4, 300314.
BotheW. (1921 b). The validity limits of Gauss’ laws for independent elementary error sources. Z Phys 4, 161177.
BozzolaJ.J., JohnsonM.C. & ShechmeiI.L. (1973). In-situ multiple sampling of attached bacteria for scanning and transmission electron-microscopy. Stain Technol 48(6), 317325.
DanilatosG.D. & PostleR. (1982). Advances in environmental and atmospheric scanning electron-microscopy. Micron 13(3), 253254.
de JongeN. & RossF.M. (2011). Electron microscopy of specimens in liquid. Nat Nanotechnol 6(11), 695704.
DemersH., RamachandraR., DrouinD. & de JongeN. (2012). The probe profile and lateral resolution of scanning transmission electron microscopy of thick specimens. Microsc Microanal 18(3), 582590.
GentschP., GildeH. & ReimerL. (1974). Measurement of top bottom effect in scanning-transmission electron-microscopy of thick amorphous specimens. J Microsc 100, 8192.
GoldsteinJ. (2003). Scanning Electron Microscopy and X-Ray Microanalysis. New York: Kluwer Academic/Plenum Publishers.
GreenE.D. & KinoG.S. (1991). Atmospheric scanning electron-microscopy using silicon-nitride thin-film windows. J Vac Sci Technol B 9(3), 15571558.
HayatM.A. (1970). Principles and Techniques of Electron Microscopy; Biological Applications. New York: Van Nostrand Reinhold Co.
HoltzM.E., YuY.C., GaoJ., AbrunaH.D. & MullerD.A. (2013). In situ electron energy-loss spectroscopy in liquids. Microsc Microanal 19(4), 10271035.
HyunJ.K., ErciusP. & MullerD.A. (2008). Beam spreading and spatial resolution in thick organic specimens. Ultramicroscopy 109(1), 17.
JacksonJ.D. (1998) [1962]. Classical Electrodynamics (3rd ed.). New York: John Wiley and Sons.
JoyD.C. (1995). Monte Carlo Modeling for Electron Microscopy and Microanalysis. New York: Oxford University Press.
MathieuC. (1998). Effects of electron-beam/gas interactions on x-ray microanalysis in the variable pressure SEM. Mikrochim Acta 15, 295300.
MoncrieffD.A., RobinsonV.N.E. & HarrisL.B. (1978). Charge neutralization of insulating surfaces in the SEM by gas ionization. J Phys D Appl Phys 11(17), 23152325.
ReimerL. (1968). Monte-Carlo calculations for electron diffusion. Optik 27(2), 86.
ReimerL. (1985). Scanning Electron Microscopy : Physics of Image Formation and Microanalysis. Berlin and New York: Springer-Verlag.
ReimerL. (1998). Scanning Electron Microscopy: Physics of Image Formation and Microanalysis. Berlin and New York: Springer.
ShahJ.S. & BeckettA. (1979). Preliminary evaluation of moist environment ambient-temperature scanning electron-microscopy. Micron 10(1), 1323.
SolomonovI., Talmi-FrankD., MilsteinY., AddadiS., AloshinA. & SagiI. (2014). Introduction of correlative light and airSEM (TM) microscopy imaging for tissue research under ambient conditions. Sci Rep 4, 17.
StokesD., Royal Microscopical Society (Great Britain) (2008). Principles and Practice of Variable Pressure/Environmental Scanning Electron Microscopy (VP-ESEM). Chichester, UK: Wiley.
SugaM., NishiyamaH., KonyubaY., IwamatsuS., WatanabeY., YoshiuraC., UedaT. & SatoC. (2011). The atmospheric scanning electron microscope with open sample space observes dynamic phenomena in liquid or gas. Ultramicroscopy 111(12), 16501658.
SwiftJ.A. & BrownA.C. (1970). Environmental cell for examination of wet biological specimens at atmospheric pressure by transmission scanning electron microscopy. J Phys E Sci Instrum 3(11), 924992.
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Microscopy and Microanalysis
  • ISSN: 1431-9276
  • EISSN: 1435-8115
  • URL: /core/journals/microscopy-and-microanalysis
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