Recent Development in Hitachi Transmission Electron Microscope

1983 ◽  
Vol 31 ◽  
Author(s):  
Shigeto Isakozawa ◽  
Isao Matsui ◽  
Shoji Kamimura ◽  
Akira Tonomura
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Image Resolution ◽  
Objective Lens ◽  
High Grade ◽  
Resolution Limit ◽  
Transmission Electron

The 200 kV electron microscope has been extensively utilized as a high grade model for diversified applications. This paper reports image resolution available at present with the Hitachi 200 kV Electron Microscope Model H-800 and possible techniques for improving present resolution limit which depends on the aberrations of objective lens.

Aberrations in the Transmission Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 352-353
Author(s):  
R.A. Ploc
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Landau Equation ◽  
Image Resolution ◽  
Bethe Equation ◽  
Aperture Size ◽  
Resolution Limit ◽  
Transmission Electron ◽  
The Mean ◽  
Pass Through

Three aberrations contribute to the loss of image resolution in the transmission electron microscope; spherical (SA=Csα3), chromatic (CA=Ccα△VV-1) and diffraction (DA=O.61ƛα-1). For high voltage incident electrons and thin materials most microscopists assume resolution is controlled by spherical and diffraction aberrations. We shall discuss whether equating the SA and DA to derive an optimum aperture size (related to αo) and resolution limit (1) is a valid procedure.To determine △V for a given material requires the use of either the Bethe or Landau equations. The Landau formula can be used to give the width of the energy spectrum and the Bethe equation, the mean energy loss after the incident electrons pass through the foil. Since the former is the most probable quantity contributing to CA, Figures 1 and 2 are based on the use of the Landau equation. Zirconium of thickness, t, will be considered for the accelerating voltages 105 and 106 eV.

A New High Resolution Transmission Electron Microscope with Second-Zone Objective Lens

1969 ◽  
Vol 27 ◽  
pp. 176-177 ◽  
Author(s):  
H. Tochigi ◽  
H. Uchida ◽  
S. Shirai ◽  
K. Akashi ◽  
D. J. Evins ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Transmission Electron Microscope ◽  
Objective Lens ◽  
High Excitation ◽  
Transmission Electron ◽  
New Instrument

A New High Excitation Objective Lens (Second-Zone Objective Lens) was discussed at Twenty-Sixth Annual EMSA Meeting. A new commercially available Transmission Electron Microscope incorporating this new lens has been completed.Major advantages of the new instrument allow an extremely small beam to be produced on the specimen plane which minimizes specimen beam damages, reduces contamination and drift.

Resolution in the Scanning Transmission Electron Microscope

1972 ◽  
Vol 30 ◽  
pp. 454-455
Author(s):  
M. G. R. Thomson
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Spherical Aberration ◽  
Signal To Noise Ratio ◽  
Scanning Transmission Electron Microscope ◽  
Dark Field ◽  
Objective Lens ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission

The variation of contrast and signal to noise ratio with change in detector solid angle in the high resolution scanning transmission electron microscope was discussed in an earlier paper. In that paper the conclusions were that the most favourable conditions for the imaging of isolated single heavy atoms were, using the notation in figure 1, either bright field phase contrast with β0⋍0.5 α0, or dark field with an annular detector subtending an angle between ao and effectively π/2.The microscope is represented simply by the model illustrated in figure 1, and the objective lens is characterised by its coefficient of spherical aberration Cs. All the results for the Scanning Transmission Electron Microscope (STEM) may with care be applied to the Conventional Electron Microscope (CEM). The object atom is represented as detailed in reference 2, except that ϕ(θ) is taken to be the constant ϕ(0) to simplify the integration. This is reasonable for θ ≤ 0.1 θ0, where 60 is the screening angle.

The theory of super-resolution electron microscopy via Wigner-distribution deconvolution

1992 ◽  
Vol 339 (1655) ◽  
pp. 521-553 ◽  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Phase Retrieval ◽  
Wigner Distribution ◽  
Super Resolution ◽  
Partial Coherence ◽  
Objective Lens ◽  
Specimen Thickness ◽  
Data Set ◽  
Transmission Electron

The theory of deconvolving the microdiffraction data-set available in a scanning transmission electron microscope or, equivalently, the set of all bright- and dark-field images available in a conventional transmission electron microscope to obtain super- resolution micrographs (which are not limited by the transfer function of the objective lens) is developed and described with reference to holography and other phase-retrieval schemes. By the use of a Wigner distribution, influences of the instrument function can be entirely separated from the information pertaining to the specimen. The final solution yields an unambiguous estimate of the complex value of the specimen function at a resolution which in theory is only limited by the electron wavelength. The faithfulness of the image processing is shown to be not seriously affected by specimen thickness or partial coherence in the illuminating beam. The inversion procedure is remarkably noise insensitive, implying that it should result in a robust and practicable experimental technique, though one that will require very large computing facilities.

Unique Features of a High Resolution Scanning Transmission Electron Microscope

1974 ◽  
Vol 32 ◽  
pp. 404-405
Author(s):  
J. W. Wiggins ◽  
M. Beer ◽  
D. C. Woodruff ◽  
J. A. Zubin
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Transmission Electron Microscope ◽  
Heavy Atom ◽  
Scanning Transmission Electron Microscope ◽  
Objective Lens ◽  
Optical Parameters ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission

A high resolution scanning transmission electron microscope has been constructed and is operating. The initial task of this instrument is to attempt the sequencing of DNA by heavy-atom specific staining. It is also suitable for many other biological investigations requiring high resolution, low contamination and minimum radiation damage.The basic optical parameters are: 20 to 100 KV acceleration potential, objective lens focal length of 1.0 mm. with Cs = 0.7 mm., and two additional lenses designated as condensor and diffraction lenses. The purpose of the condensor lens is to provide a parallel beam incident to the objective, and the diffraction lens produces an image of the back focal plane of the objective in the plane of an annular detector.

Assessing the Fundamental Limits of Electron-Beam Imaging

1987 ◽  
Vol 45 ◽  
pp. 2-3
Author(s):  
Linn W. Hobbs
Keyword(s):  
Image Processing ◽  
Electron Beam ◽  
Electron Microscope ◽  
Spherical Aberration ◽  
Image Resolution ◽  
Beam Optics ◽  
Resolution Limit ◽  
Fundamental Limits ◽  
Transmission Electron ◽  
Nobel Prize In Physics

A long-overdue Nobel Prize in Physics for the development of the transmission electron microscope was awarded in 1986 to Professor Dr. Ernst Ruska, some fifty-three years after his demonstration of the superiority of electron-beam imaging. The microscope originally designed by Ruska did not differ significantly from the instruments in use today, a half century later, nor were early practitioners unaware of the image resolution potential inherent in electron-beam optics. We are now, at last, running into the limits of that potential, at least as judged by the quantity of effort expended for increasingly diminishing returns. The present point-resolution limit under axial illumination stands at about 0.15 nm and is unlikely to be lowered significantly without signal successes in design and application of novel correction schemes for spherical aberration or in sophistication of interactive image processing methods.

Development of a Real-Time Elemental Mapping System in a Scanning Transmission Electron Microscope

2000 ◽  
Vol 6 (S2) ◽  
pp. 178-179
Author(s):  
K. Kaji Ueda ◽  
T. Aoyama ◽  
S. Taya ◽  
H. Tanaka ◽  
S. Isakozawa
Keyword(s):  
Electron Microscope ◽  
Real Time ◽  
Transmission Electron Microscope ◽  
Scanning Transmission Electron Microscope ◽  
Objective Lens ◽  
Elemental Mapping ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Mapping System ◽  
Scanning Transmission

The ability to obtain elemental maps in a transmission electron microscope (TEM) or scanning transmission electron microscope (STEM) is extremely useful in the analysis of materials, and semiconductor devices such as ULSI's and GMR heads. Hitachi has developed a new type of elemental mapping system, consisting of a STEM (Hitachi, HD-2000) equipped with a two-window electron energy filter. In-situ calculation of the energy-filtered signal makes it possible to observe real time elemental mapping images with nanometer resolution.Figure 1 shows a schematic of the elemental mapping system. In the STEM, electrons are generated from a cold field emission gun and accelerated to a potential of 200 kV. The electrons arc focused by the objective lens into a small probe (<1 nm), which is then rastered over the specimen using scanning coils. Transmitted electrons are collected by an energy filter, which is located beneath the specimen., and consists of quadrupole lenses, a magnetic prism spectrometer and two kinds of electron beam energy detectors.

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