A5069695916- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Advanced X-ray Imaging Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Advanced Materials Characterization Techniques
- Surface and Thin Film Phenomena
- Force Microscopy Techniques and Applications
- Ion-surface interactions and analysis
- Crystallography and Radiation Phenomena
- Molecular Junctions and Nanostructures
- Advancements in Photolithography Techniques
- Carbon Nanotubes in Composites
- Graphene research and applications
- X-ray Spectroscopy and Fluorescence Analysis
- Catalytic Processes in Materials Science
- Nuclear Physics and Applications
- Fullerene Chemistry and Applications
- Quantum and electron transport phenomena
- Near-Field Optical Microscopy
- Electrocatalysts for Energy Conversion
- Advanced Surface Polishing Techniques
- Advancements in Battery Materials
- Magnetic properties of thin films
- Particle Detector Development and Performance
- Electronic and Structural Properties of Oxides
JEOL (Japan)
2011-2020
Japan Science and Technology Agency
1997-2012
Tokyo Electron (Japan)
2001-2010
Japan Fine Ceramics Center
2009
The University of Tokyo
2009
Kyoto Institute of Technology
2009
Tohoku University
2009
Advanced Institute of Materials Science
2009
Centre de Recherche en Économie et Statistique
2008
Centre for Research in Engineering Surface Technology
2008
Suspended gold nanowires were made in an ultra-high vacuum. The finest of them was 0.6 nanometer diameter and 6 nanometers length. By high-resolution electron microscopy, they shown to have a multi-shell structure composed coaxial tubes. Each tube consists helical atom rows coiled round the wire axis. difference between numbers outer inner shells is seven, resulting magic shell-closing numbers.
We formed gold nanowires using electron-beam irradiation in an ultrahigh vacuum electron microscope. The dimensions of these were 0.8--3 nm thickness and 5--10 length. showed lasting stability. propose a structure model for nanowire with 2 nm. is represented by hexagonal prism; the surface layer prism has hexagonal-close-packed (hcp) lattice, core face-centered-cubic structure. considered to be stabilized hcp lattices surfaces.
We show that an annular detector placed within the bright field cone in scanning transmission electron microscopy allows direct imaging of light elements crystals. In contrast to common high angle dark imaging, both and heavy atom columns are visible simultaneously. images directly robustly interpretable over a large range thicknesses. demonstrate this through systematic simulations present simple physical model obtain some insight into scattering dynamics.
Abstract The aberration-corrected scanning transmission electron microscope (STEM) has emerged as a key tool for atomic resolution characterization of materials, allowing the use imaging modes such Z -contrast and spectroscopic mapping. STEM not been regarded optimal phase-contrast necessary efficient light materials. Here, recent developments in fast detectors data processing capability is shown to enable ptychography, extend by quantitative phase images be formed simultaneously with...
Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – 30,
A spherical aberration-corrected electron microscope has been developed recently, which is equipped with a 300-kV cold field emission gun and an objective lens of small chromatic aberration coefficient. dumbbell image 47 pm spacing, corresponding to pair atomic columns germanium aligned along the [114] direction, resolved in high-angle annular dark (HAADF) scanning transmission microscopy (STEM) 0.4-eV energy spread beam. The observed was compared simulated obtained by dynamical calculation.
A new area detector for atomic-resolution scanning transmission electron microscopy (STEM) is developed and tested. The circular divided into 16 segments which are individually optically coupled with photomultiplier tubes. Thus, STEM images sensitive to the spatial distribution of scattered electrons on plane can be simultaneously obtained. This potentially used not only simultaneous formation common bright-field, low-angle annular dark-field high-angle images, but also quantification by...
We report on a new camera that is based pnCCD sensor for applications in scanning transmission electron microscopy. Emerging microscopy techniques demand improved detectors with regards to readout rate, sensitivity and radiation hardness, especially mode. The 2D imaging meets these requirements. Its intrinsic hardness permits direct detection of electrons. read out at rate 1,150 frames per second an image area 264 x pixel. In binning or windowing modes, the increased almost linearly, example...
This report introduces the first results obtained using phase-contrast scanning transmission electron microscopy (P-STEM). A carbon-film phase plate (PP) with a small center hole is placed in condenser aperture plane so that shift introduced incident waves except those passing through hole. cosine-type transfer function emerges when phase-shifted scattered interfere non-phase-shifted unscattered waves, which passed before incidence onto specimen. The contrast resulting P-STEM optically...
We visualized lithium atom columns in LiV2O4 crystals by combining scanning transmission electron microscopy with annular bright field (ABF) imaging using a spherical aberration-corrected microscope (R005) viewed from the [110] direction. The incident beam was coherent convergent angle of 30 mrad (semi-angle), and detector collected scattered electrons over 20–30 (semi-angle). ABF image showed dark dots corresponding to lithium, vanadium oxygen columns.
Recent development in fast pixelated detector technology has allowed a two dimensional diffraction pattern to be recorded at every probe position of raster scan scanning transmission electron microscope (STEM), forming an information-rich four (4D) dataset. Electron ptychography been shown enable efficient coherent phase imaging weakly scattering objects from 4D dataset using focused probe, which is optimised for simultaneous incoherent Z-contrast and spectroscopy STEM. Therefore contrast...
A suspended platinum nanowire was observed to have the same helical multishell structure (HMS) that reported for gold nanowires thinner than 2 nm. The investigation made in an ultrahigh vacuum high-resolution electron microscope (JEM-2000VF). synthesized by electron-beam thinning method at elevated temperatures enhance Pt atom migration. thinned migration until it finally snapped. In meantime, outer shell stripped from a 13-6 HMS partially expose inner shell. Simulated images supported...
The development of a method for the precise measurement strain fields in semiconductor devices has become critical requirement because electrical performances are greatly influenced by induced their structures. We applied scanning moiré fringe imaging to demonstrate quantitative mapping Si/Si1−xGex interfacial layer. field was measured at nano-meter scale spatial resolution, with detection precision 0.1%. maximum value be 1.1% ± 0.1%, which is consistent direct high-resolution transmission...
Novel spherical aberration (Cs) and chromatic (Cc) correctors, which correct aberrations using a new principle, were developed. The asymmetric Cs correctors designed for use in the probe- image-forming systems at 300 kV to diminish undesired parasitic aberrations. composed of non-equivalent multipoles connecting with demagnifying transfer doublet system. axial corrected well up fifth order except 6-fold astigmatism (A(6)) experimentally. Next, we developed superior low voltage microscope...
Phase contrast imaging is widely used for beam sensitive and weak phase objects in electron microscopy. In this work we demonstrate the achievement of high efficient STEM using pnCCD, a fast direct pixelated detector, which records diffraction patterns at every probe position with speed 1000 to 4000 frames per second, forming 4D dataset simultaneously incoherent Z-contrast imaging. Ptychographic reconstruction has been applied obtained complex transmission function reveals specimen. The...
Abstract Covalently bonded crystalline substances with micropores have broad applications. Covalent organic frameworks (COFs) are representative of such substances. They so far been classified into two-dimensional (2D) and three-dimensional (3D) COFs. 2D-COFs planar shapes useful for purposes, but obtaining good crystals sizes larger than 10 μm is significantly challenging, whereas yielding 3D-COFs high crystallinity easier. Here, we show COFs 2.5-dimensional (2.5D) skeletons, which...
Transition of gold (001) nanofilm to a (111) was observed in an ultrahigh vacuum electron microscope. The critical thickness the measured by holography be eight atom layers. These nanofilms ranged from 2 20 nm length. Analyzing high resolution microscopy and diffraction, lattice spacing film isotropically compressed $3.1%$-- $3.6%$, similar hexagonal $5\ifmmode\times\else\texttimes\fi{}20$ surface reconstruction. experiments show that structure is dominated surfaces.
The performance of a newly developed high-resolution 300 kV microscope equipped with spherical aberration corrector for probe-forming systems is reported. This gave the highest resolution distance between atomic columns, as determined by high-angle annular dark field imaging method using GaN[211] crystalline specimen, where neighboring columns Ga was 63 pm.
Carbon nanotubes have been synthesized by heat treating the polymer at 400 °C in air which was obtained polyesterification between citric acid and ethylene glycol. Transmission electron micrographs an diffraction pattern showed formation of carbon nanotubes. The diameter tubes ranged from 5 to 20 nm, whereas lengths were less than 1 μm.