Analysis of crystal defects by scanning transmission electron microscopy (STEM) in a modern scanning electron microscope

Abstract Recent developments in transmission electron microscopy (TEM) sample preparation have greatly reduced the time and cost for preparing thin samples. In this paper, a method is demonstrated for viewing thin samples in transmission in an unmodified scanning electron microscope (SEM) using an easily constructed sample holder. Although not a substitute for true TEM analysis, this method allows for spatial resolution that is superior to typical SEM imaging and provides image contrast from material structure that is typical of TEM images. Furthermore, the method can produce extremely high resolution x-ray maps that are typically produced only by scanning transmission electron microscope (STEM) systems.

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Electron Tomography of HEK293T Cells Using Scanning Electron Microscope–Based Scanning Transmission Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927612001158 ◽

2012 ◽

Vol 18 (5) ◽

pp. 1037-1042 ◽

Cited By ~ 1

Author(s):

Yun-Wen You ◽

Hsun-Yun Chang ◽

Hua-Yang Liao ◽

Wei-Lun Kao ◽

Guo-Ji Yen ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Scanning Transmission Electron Microscopy ◽

Electron Tomography ◽

Transmission Electron ◽

Scanning Transmission ◽

3D Volume ◽

Scanning Electron

AbstractBased on a scanning electron microscope operated at 30 kV with a homemade specimen holder and a multiangle solid-state detector behind the sample, low-kV scanning transmission electron microscopy (STEM) is presented with subsequent electron tomography for three-dimensional (3D) volume structure. Because of the low acceleration voltage, the stronger electron-atom scattering leads to a stronger contrast in the resulting image than standard TEM, especially for light elements. Furthermore, the low-kV STEM yields less radiation damage to the specimen, hence the structure can be preserved. In this work, two-dimensional STEM images of a 1-μm-thick cell section with projection angles between ±50° were collected, and the 3D volume structure was reconstructed using the simultaneous iterative reconstructive technique algorithm with the TomoJ plugin for ImageJ, which are both public domain software. Furthermore, the cross-sectional structure was obtained with the Volume Viewer plugin in ImageJ. Although the tilting angle is constrained and limits the resulting structural resolution, slicing the reconstructed volume generated the depth profile of the thick specimen with sufficient resolution to examine cellular uptake of Au nanoparticles, and the final position of these nanoparticles inside the cell was imaged.

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On the Progress of Scanning Transmission Electron Microscopy (STEM) Imaging in a Scanning Electron Microscope

Microscopy and Microanalysis ◽

10.1017/s1431927618000181 ◽

2018 ◽

Vol 24 (2) ◽

pp. 99-106 ◽

Cited By ~ 14

Author(s):

Cheng Sun ◽

Erich Müller ◽

Matthias Meffert ◽

Dagmar Gerthsen

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Crystal Defects ◽

Low Energy ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Electron Microscopes ◽

Scanning Electron

AbstractTransmission electron microscopy (TEM) with low-energy electrons has been recognized as an important addition to the family of electron microscopies as it may avoid knock-on damage and increase the contrast of weakly scattering objects. Scanning electron microscopes (SEMs) are well suited for low-energy electron microscopy with maximum electron energies of 30 keV, but they are mainly used for topography imaging of bulk samples. Implementation of a scanning transmission electron microscopy (STEM) detector and a charge-coupled-device camera for the acquisition of on-axis transmission electron diffraction (TED) patterns, in combination with recent resolution improvements, make SEMs highly interesting for structure analysis of some electron-transparent specimens which are traditionally investigated by TEM. A new aspect is correlative SEM, STEM, and TED imaging from the same specimen region in a SEM which leads to a wealth of information. Simultaneous image acquisition gives information on surface topography, inner structure including crystal defects and qualitative material contrast. Lattice-fringe resolution is obtained in bright-field STEM imaging. The benefits of correlative SEM/STEM/TED imaging in a SEM are exemplified by structure analyses from representative sample classes such as nanoparticulates and bulk materials.

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

Microscopy and Microanalysis ◽

10.1017/s1431927616011405 ◽

2016 ◽

Vol 22 (4) ◽

pp. 754-767 ◽

Cited By ~ 3

Author(s):

Kayla X. Nguyen ◽

Megan E. Holtz ◽

Justin Richmond-Decker ◽

David A. Muller

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Vacuum Chamber ◽

Operating Conditions ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron

AbstractA 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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The fine structure of fenestrated adrenocortical capillaries revealed by in-lens field-emission scanning electron microscopy and scanning transmission electron microscopy

Scanning ◽

10.1002/sca.4950190503 ◽

1997 ◽

Vol 19 (5) ◽

pp. 361-367 ◽

Cited By ~ 13

Author(s):

Robert P. Apkarian

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Field Emission ◽

Scanning Transmission Electron Microscopy ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron

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Scanning transmission electron microscopy—vacuum generators' HB5 field emission source scanning transmission electron microscope

Micron (1969) ◽

10.1016/0047-7206(72)90015-5 ◽

1972 ◽

Vol 4 (1) ◽

pp. 139-141

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Microscope ◽

Field Emission ◽

Transmission Electron Microscope ◽

Scanning Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscope ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

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Cryo-Scanning Electron Microscopy (SEM) and Scanning Transmission Electron Microscopy (STEM)-in-SEM for Bio- and Organo-Mineral Interface Characterization in the Environment

Microscopy and Microanalysis ◽

10.1017/s143192761701265x ◽

2017 ◽

Vol 23 (6) ◽

pp. 1159-1172 ◽

Cited By ~ 2

Author(s):

Guillaume Wille ◽

Jennifer Hellal ◽

Patrick Ollivier ◽

Annie Richard ◽

Agnes Burel ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Fluorescent Microscopy ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Cryo Scanning Electron Microscopy ◽

Scanning Electron

AbstractUnderstanding biofilm interactions with surrounding substratum and pollutants/particles can benefit from the application of existing microscopy tools. Using the example of biofilm interactions with zero-valent iron nanoparticles (nZVI), this study aims to apply various approaches in biofilm preparation and labeling for fluorescent or electron microscopy and energy dispersive X-ray spectrometry (EDS) microanalysis for accurate observations. According to the targeted microscopy method, biofilms were sampled as flocs or attached biofilm, submitted to labeling using 4’,6-diamidino-2-phenylindol, lectins PNA and ConA coupled to fluorescent dye or gold nanoparticles, and prepared for observation (fixation, cross-section, freezing, ultramicrotomy). Fluorescent microscopy revealed that nZVI were embedded in the biofilm structure as aggregates but the resolution was insufficient to observe individual nZVI. Cryo-scanning electron microscopy (SEM) observations showed nZVI aggregates close to bacteria, but it was not possible to confirm direct interactions between nZVI and cell membranes. Scanning transmission electron microscopy in the SEM (STEM-in-SEM) showed that nZVI aggregates could enter the biofilm to a depth of 7–11µm. Bacteria were surrounded by a ring of extracellular polymeric substances (EPS) preventing direct nZVI/membrane interactions. STEM/EDS mapping revealed a co-localization of nZVI aggregates with lectins suggesting a potential role of EPS in nZVI embedding. Thus, the combination of divergent microscopy approaches is a good approach to better understand and characterize biofilm/metal interactions.

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Scanning Transmission Electron Microscopy of Polyethylene Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001069 ◽

1980 ◽

Vol 38 ◽

pp. 242-245

Author(s):

F. Khoury ◽

L. H. Bolz

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallization Temperature ◽

Scanning Transmission Electron Microscopy ◽

Growth Habit ◽

Lateral Growth ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Growth Habits

The lateral growth habits and non-planar conformations of polyethylene crystals grown from dilute solutions (<0.1% wt./vol.) are known to vary depending on the crystallization temperature.1-3 With the notable exception of a study by Keith2, most previous studies have been limited to crystals grown at <95°C. The trend in the change of the lateral growth habit of the crystals with increasing crystallization temperature (other factors remaining equal, i.e. polymer mol. wt. and concentration, solvent) is illustrated in Fig.l. The lateral growth faces in the lozenge shaped type of crystal (Fig.la) which is formed at lower temperatures are {110}. Crystals formed at higher temperatures exhibit 'truncated' profiles (Figs. lb,c) and are bound laterally by (110) and (200} growth faces. In addition, the shape of the latter crystals is all the more truncated (Fig.lc), and hence all the more elongated parallel to the b-axis, the higher the crystallization temperature.

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