Three-dimensional real-space crystallography of MCM-48 mesoporous silica revealed by scanning transmission electron tomography

A significant change in microstructure occurs during the application of severe plastic deformation (SPD) such as by equal-channel angular pressing (ECAP). In this study, intense plastic strain was imposed on an Al-10.8wt%Ag alloy by the ECAP process. The amount of strain was controlled by the numbers of passes. After 1 pass of ECAP, shear bands became visible within the matrix. With increasing numbers of ECAP passes, the fraction of shear bands was increased. In this study, the change in microstructures was examined by three-dimensional electron tomography (3D-ET) in transmission electron microscopy (TEM) or scanning transmission electron microscopy (STEM). With this 3D-ET method, it was possible to conduct a precise analysis of the sizes, widths and distributions of the shear bands produced by the ECAP process. It is demonstrated that the 3D-ET method is promising to understand mechanisms of microstructural refinement using the ECAP process.

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Facets, indium distribution, and lattice distortion of InGaAs/GaAs quantum dots observed by three-dimensional scanning transmission electron microscope

Journal of Applied Physics ◽

10.1063/1.1572976 ◽

2003 ◽

Vol 94 (1) ◽

pp. 313-317 ◽

Cited By ~ 18

Author(s):

Kazunari Ozasa ◽

Yoshinobu Aoyagi ◽

Masaya Iwaki ◽

Hiroki Kurata

Keyword(s):

Quantum Dots ◽

Electron Microscope ◽

Transmission Electron Microscope ◽

Lattice Distortion ◽

Three Dimensional ◽

Scanning Transmission Electron Microscope ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

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Three-dimensional scanning transmission electron microscopy of dislocation loops in tungsten

Micron ◽

10.1016/j.micron.2018.05.010 ◽

2018 ◽

Vol 113 ◽

pp. 24-33 ◽

Cited By ~ 9

Author(s):

S. Hasanzadeh ◽

R. Schäublin ◽

B. Décamps ◽

V. Rousson ◽

E. Autissier ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Three Dimensional ◽

Dislocation Loops ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

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Three-Dimensional Scanning Transmission Electron Microscopy of Biological Specimens

Microscopy and Microanalysis ◽

10.1017/s1431927609991280 ◽

2010 ◽

Vol 16 (1) ◽

pp. 54-63 ◽

Cited By ~ 37

Author(s):

Niels de Jonge ◽

Rachid Sougrat ◽

Brian M. Northan ◽

Stephen J. Pennycook

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Mammalian Cells ◽

Three Dimensional ◽

Axial Resolution ◽

Beam Radiation ◽

Thin Sections ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

AbstractA three-dimensional (3D) reconstruction of the cytoskeleton and a clathrin-coated pit in mammalian cells has been achieved from a focal-series of images recorded in an aberration-corrected scanning transmission electron microscope (STEM). The specimen was a metallic replica of the biological structure comprising Pt nanoparticles 2–3 nm in diameter, with a high stability under electron beam radiation. The 3D dataset was processed by an automated deconvolution procedure. The lateral resolution was 1.1 nm, set by pixel size. Particles differing by only 10 nm in vertical position were identified as separate objects with greater than 20% dip in contrast between them. We refer to this value as the axial resolution of the deconvolution or reconstruction, the ability to recognize two objects, which were unresolved in the original dataset. The resolution of the reconstruction is comparable to that achieved by tilt-series transmission electron microscopy. However, the focal-series method does not require mechanical tilting and is therefore much faster. 3D STEM images were also recorded of the Golgi ribbon in conventional thin sections containing 3T3 cells with a comparable axial resolution in the deconvolved dataset.

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Thickness and Stacking Sequence Determination of Exfoliated Dichalcogenides (1T-TaS2, 2H-MoS2) Using Scanning Transmission Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927618012436 ◽

2018 ◽

Vol 24 (4) ◽

pp. 387-395 ◽

Cited By ~ 5

Author(s):

Robert Hovden ◽

Pengzi Liu ◽

Noah Schnitzer ◽

Adam W. Tsen ◽

Yu Liu ◽

...

Keyword(s):

Transition Metal Dichalcogenides ◽

Single Layer ◽

Atomic Layer ◽

Real Space ◽

Dark Field ◽

Crystal Thickness ◽

Stacking Sequence ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

AbstractLayered transition metal dichalcogenides (TMDs) have attracted interest due to their promise for future electronic and optoelectronic technologies. As one approaches the two-dimensional (2D) limit, thickness and local topology can greatly influence the macroscopic properties of a material. To understand the unique behavior of TMDs it is therefore important to identify the number of atomic layers and their stacking in a sample. The goal of this work is to extract the thickness and stacking sequence of TMDs directly by matching experimentally recorded high-angle annular dark-field scanning transmission electron microscope images and convergent-beam electron diffraction (CBED) patterns to quantum mechanical, multislice scattering simulations. Advantageously, CBED approaches do not require a resolved lattice in real space and are capable of neglecting the thickness contribution of amorphous surface layers. Here we demonstrate the crystal thickness can be determined from CBED in exfoliated 1T-TaS2 and 2H-MoS2 to within a single layer for ultrathin ≲9 layers and ±1 atomic layer (or better) in thicker specimens while also revealing information about stacking order—even when the crystal structure is unresolved in real space.

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