Direct observations of semithin sections by the use of TEM and STEM

It has been routin to cut semithin sections to look for desired areas before cutting ultrathin sections for electron microscope studies. A new method made it possible to observe larger semithin sections of epoxy resin-embedded tissue with both light microscope and two kinds of electron microscopes,: Transmission Electron Microscope and Scanning Transmission Electron Microscope.Samples obtained from kidneys of rats and mice were sliced to 0. 5.mm to 1 mm thickness. They were fixed for 4 hours in Sorensen phosphate buffer of pH 7.4, containing 2 % glutaraldehyde and 1.5 % paraformaldehyde, rinsed in plain buffer for 12 hours (overnight) and postfixed in 1 % osmium tetroxide buffered with phosphate for 90 minutes. The tissu blocks were then embedded in epoxy resin in a ratio of 6:4 or 5:5 by weight, based on the method of Luft.

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Development of a 1MV-Field-Emission Electron Microscope I. Instrument

Microscopy and Microanalysis ◽

10.1017/s1431927600038186 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 1138-1139

Author(s):

I. Matsui ◽

T. Katsuta ◽

T. Kawasaki ◽

S. Hayashi ◽

T. Furutsu ◽

...

Keyword(s):

Electron Microscope ◽

Field Emission ◽

Transmission Electron Microscope ◽

Scanning Transmission Electron Microscope ◽

Electron Holography ◽

Lorentz Microscopy ◽

Transmission Electron ◽

Scanning Transmission ◽

Resolution Imaging ◽

Electron Microscopes

We have developed 100-kV, 200-kV, and 350-kV cold-field-emission transmission electron microscopes (FE-TEMs) successively up to this time. Using these instruments, we have been studying the magnetic structure of materials, high-resolution imaging by electron holography, and dynamic observation of the vortex in superconductors by Lorentz microscopy. To make more progress in our research, we need a better electron beam in terms of coherency, beam brightness, and penetration. Here, we report a new lMV-cold-field-emission transmission electron microscope we have developed. Historically, the pioneering projects on a lMV-field-emission scanning transmission electron microscope (FE-STEM) (Zeitler and Crewe, 1974) and a 1.6MV FE-STEM (Jouffrey et al., 1984) have been reported. In 1988, Maruse and Shimoyama obtained a lMV-field-emission beam using their 1.25MV-STEM connected to a field-emission gun. Since then, continuous improvements in beam brightness has been made.The target specifications of our 1 MV-cold-field-emission TEM (H-1000FT) are as follows: Acceleration voltage: 1MV, high-voltage stability :

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Tuning Fifth-Order Aberrations in a Quadrupole-Octupole Corrector

Microscopy and Microanalysis ◽

10.1017/s1431927612001237 ◽

2012 ◽

Vol 18 (4) ◽

pp. 699-704 ◽

Cited By ~ 3

Author(s):

Andrew R. Lupini ◽

Stephen J. Pennycook

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Spherical Aberration ◽

Scanning Transmission Electron Microscope ◽

Low Energy ◽

Third Order ◽

Transmission Electron ◽

Scanning Transmission ◽

Electron Microscopes ◽

Fifth Order

AbstractThe resolution of conventional electron microscopes is usually limited by spherical aberration. Microscopes equipped with aberration correctors are then primarily limited by higher order, chromatic, and misalignment aberrations. In particular the Nion third-order aberration correctors installed on machines with a low energy spread and possessing sophisticated alignment software were limited by the uncorrected fifth-order aberrations. Here we show how the Nion fifth-order aberration corrector can be used to adjust and reduce some of the fourth- and fifth-order aberrations in a probe-corrected scanning transmission electron microscope.

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A General Method for Spectrometer Design in the Scoff Approximation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092657 ◽

1976 ◽

Vol 34 ◽

pp. 538-539

Author(s):

J. R. Fields

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Energy Analysis ◽

Incident Beam ◽

Scanning Transmission Electron Microscope ◽

Chemical Identification ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

General Method

The energy analysis of electrons scattered by a specimen in a scanning transmission electron microscope can improve contrast as well as aid in chemical identification. In so far as energy analysis is useful, one would like to be able to design a spectrometer which is tailored to his particular needs. In our own case, we require a spectrometer which will accept a parallel incident beam and which will focus the electrons in both the median and perpendicular planes. In addition, since we intend to follow the spectrometer by a detector array rather than a single energy selecting slit, we need as great a dispersion as possible. Therefore, we would like to follow our spectrometer by a magnifying lens. Consequently, the line along which electrons of varying energy are dispersed must be normal to the direction of the central ray at the spectrometer exit.

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Resolution in the Scanning Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095522 ◽

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.

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Measurement of lattice parameter at the nanometer scale using convergent-beam microdiffraction from a thermal emission source

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149283 ◽

1993 ◽

Vol 51 ◽

pp. 690-691

Author(s):

W. T. Pike

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Thermal Emission ◽

Lattice Parameter ◽

Scanning Transmission Electron Microscope ◽

Emission Source ◽

Device Structure ◽

Transmission Electron ◽

Scanning Transmission ◽

Convergent Beam

With the advent of crystal growth techniques which enable device structure control at the atomic level has arrived a need to determine the crystal structure at a commensurate scale. In particular, in epitaxial lattice mismatched multilayers, it is of prime importance to know the lattice parameter, and hence strain, in individual layers in order to explain the novel electronic behavior of such structures. In this work higher order Laue zone (holz) lines in the convergent beam microdiffraction patterns from a thermal emission transmission electron microscope (TEM) have been used to measure lattice parameters to an accuracy of a few parts in a thousand from nanometer areas of material.Although the use of CBM to measure strain using a dedicated field emission scanning transmission electron microscope has already been demonstrated, the recording of the diffraction pattern at the required resolution involves specialized instrumentation. In this work, a Topcon 002B TEM with a thermal emission source with condenser-objective (CO) electron optics is used.

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Development of Line Analysis and Real-Time Elemental Mapping System in Stem Equipped with a Two-Window Energy Filter

Microscopy and Microanalysis ◽

10.1017/s1431927600031743 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 1134-1135

Author(s):

K. Kaji ◽

T. Aoyama ◽

S. Taya ◽

S. Isakozawa

Keyword(s):

Electron Microscope ◽

Energy Loss ◽

Transmission Electron Microscope ◽

Scanning Transmission Electron Microscope ◽

Elemental Mapping ◽

Additional Function ◽

Edge Structure ◽

Transmission Electron ◽

Mapping System ◽

Scanning Transmission

The ability to obtain elemental maps processed by using inelastically scattered electrons in a transmission electron microscope (TEM) or a scanning transmission electron microscope (STEM) is extremely useful in the analysis of materials, and semiconductor devices such as ULSI’s and GMR heads. Electron energy loss spectra (EELS) also give useful information not only to identify unknown materials but also to study chemical bonding states of the objective atoms. Hitachi developed an elemental mapping system, consisting of a STEM (Hitachi, HD- 2000) equipped with a two-window energy filter (Hitachi, ELV-2000), and performed realtime conventional jump-ratio images with nanometer resolution by in-situ calculation of energy-filtered signals [1]. Additional function of acquiring EELS along any lines on specimen has been developed in this system to investigate the energy loss near edge structure (ELNES).Figure 1 shows a schematic figure of the two-window energy filter, consisting of two quadrupole lenses for focusing and zooming spectra, respectively, a magnetic prism spectrometer, a deflection coil and two kinds of electron beam detectors.

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