scholarly journals Design of an Einzel Lens with Square Cross-Section

Electronics ◽  
2021 ◽  
Vol 10 (19) ◽  
pp. 2338
Author(s):  
Michał Krysztof
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Cross Section ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Beam Current ◽  
Electron Beam Current ◽  
Beam Spot ◽  
High Vacuum Chamber ◽  
Beam Spot Diameter

In this paper, the results of modeling and simulation of a microcolumn are presented. The microcolumn is part of a developed miniature MEMS electron microscope equipped with a miniature MEMS high-vacuum micropump. Such an arrangement makes this device the first stand-alone miniature electron-optical device to operate without an external high-vacuum chamber. Before such a device can be fabricated, research on particular elements must be carried out to determine the working principles of the device. The results of the calculations described in this article help us to understand the work of a microcolumn with square holes in the electrodes. The formation of an electron beam spot at the anode is discussed. Further calculations and results show the dependence of the Einzel lens size on the electron beam spot diameter, electron beam current, and microcolumn focusing voltage. The results are used to define the optimal design of the developed MEMS electron microscope.

Low Cost 210K Gain Transmission Electron Microscope Image (TEMI) Intensifier

1981 ◽  
Vol 39 ◽  
pp. 382-383
Author(s):  
R.G. Rosemeier ◽  
M.E. Taylor ◽  
A.G. Wylie
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Low Cost ◽  
Beam Current ◽  
High Gain ◽  
Electron Beam Current ◽  
Transmission Electron ◽  
Fiber Materials ◽  
Beam Currents

There are a number of factors that limit transmission electron microscope (TEM) characterization. For example, when it is necessary to statistically assess large numbers of samples quickly, conventional time consuming film recording is not a plausible solution. In the case of many electron beam sensitive biological, polymeric, and fiber materials, great care must be taken to avoid both specimen damage or structure change by using minimum electron beam current densities. On the other hand, for mineral specimens, which are in general difficult to thin, maximum electron beam currents may not be high enough to produce anything but faint TEM images. As a result, a low cost portable TEM image (TEMI) intensifier was developed that allows both direct viewing of faint electron diffraction phenomenon as well as conventional TEM viewing. Figure 1 shows the portable high gain TEMI intensifier.

scholarly journals Electron Beam Welding for Extremely High Vacuum Chamber.

Shinku ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 561-564
Author(s):  
Hiroshi KOMURO ◽  
Seiichi FURUTATE ◽  
Tsuneo ISHIGAKI ◽  
Katsujiro ITOH ◽  
Hajime ISHIMARU
Keyword(s):  
Electron Beam ◽  
Vacuum Chamber ◽  
Electron Beam Welding ◽  
High Vacuum ◽  
High Vacuum Chamber

Development of fast heating electron beam annealing setup for ultra high vacuum chamber

2014 ◽  
Vol 85 (2) ◽  
pp. 025107 ◽  
Author(s):  
Sadhan Chandra Das ◽  
Abhijit Majumdar ◽  
Sumant Katiyal ◽  
T. Shripathi ◽  
R. Hippler
Keyword(s):  
Electron Beam ◽  
Vacuum Chamber ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Fast Heating ◽  
High Vacuum Chamber ◽  
Ultra High Vacuum Chamber

Characterization of a Fixed Beam Electron Microscope with a Field Emission Gun

1976 ◽  
Vol 34 ◽  
pp. 526-527
Author(s):  
Wah Chiu ◽  
Robert M. Glaeser
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Field Emission ◽  
Current Density ◽  
Beam Current ◽  
Beam Current Density ◽  
Objective Lens ◽  
Electron Beam Current ◽  
Beam Electron ◽  
Fixed Beam

One of the objectives of our research program is to obtain a 2.0 Å point to point resolution in a fixed beam bright field electron microscope. The resolution in the fixed beam electron microscope is limited by a number of factors: electron beam coherence, energy spread, objective lens stability, mechanical stability, and specimen stability. This paper presents systematic studies of the mentioned factors in our JEM 100B fixed beam electron microscope equipped with a field emission gun operating at ∼ 1800°K.The most important characteristic of a field emission gun is its high brightness in the emitter source. In order to estimate the brightness at the specimen plane, one needs to measure the electron beam current density and the angle of illumination. The electron beam current density has been measured by means of a lithium-drifted silicon detector located below the normal position of the photographic plates. The angle of illumination can be estimated from the size of the condenser aperture and its distance from the specimen plane.

Cathodoluminescence of SiO2/Si System

2009 ◽  
Vol 156-158 ◽  
pp. 487-492 ◽  
Author(s):  
M.V. Zamoryanskaya
Keyword(s):  
Activation Energy ◽  
Electron Beam ◽  
Rise Time ◽  
Silicon Oxide ◽  
Beam Current ◽  
Electron Beam Current ◽  
Electron Traps ◽  
Definition Of ◽  
Luminescent Centers

In this paper the new method for determination of luminescent centers concentration are discussed. While the possibility of electron traps determination and definition of its activation energy are suggested. The cathodoluminescent (CL) method was used. The determination of luminescent centers concentration in silicon oxide is based on the measurements of dependences of CL intensity on electron beam current. The presence and energy of activation of electron traps were studied by measurement of rise time and decay of luminescent band during the stationary irradiation of silica by electron beam.

scholarly journals The Corrosion Studies of Electron Beam Welded Nickel Alloy

2019 ◽  
Vol 253 ◽  
pp. 03005 ◽  
Author(s):  
M. Sroka ◽  
E. Jonda ◽  
M. Węglowski ◽  
S. Błacha
Keyword(s):  
Electron Beam ◽  
Process Parameters ◽  
Microstructural Analysis ◽  
Solidification Process ◽  
Beam Current ◽  
Surface Oxide Layer ◽  
Electron Beam Current ◽  
Corrosion Properties ◽  
Inconel 617 ◽  
Potentiodynamic Anodic Polarization

The paper presents the influence of electron - beam (EB) remelting effect on the surface layer electrochemical parameters obtained from potentiodynamic anodic polarization studies and impedance spectroscopy measurements for a set of Inconel 617 electron beam remelted obtained for different process parameters. The correlation between EBW process parameters and characteristic of surface oxide layer properties and resistance to the acidic environment were discussed. The electrochemical studies were supported by microstructural analysis of the remelted zone (RZ), heat affected zone (HAZ), native metal and observed precipitates formed under rapid solidification process. Both electrochemical technics applied to evaluate corrosion properties of remelted Inconel 617 evidenced a strong influence of the electron beam current on the corrosion resistance.

scholarly journals NUMERICAL ANALYSIS OF LASING DYNAMICS IN VOLUME FREE ELECTRON LASER

2008 ◽  
Vol 13 (2) ◽  
pp. 263-273
Author(s):  
Svetlana Sytova
Keyword(s):  
Electron Beam ◽  
Free Electron ◽  
Free Electron Laser ◽  
Initial Conditions ◽  
Beam Current ◽  
Beam Current Density ◽  
Electron Beam Current ◽  
Nonlinear Phenomena ◽  
Experimental Development ◽  
Lasing Dynamics

Nonlinear phenomena originating in volume free electron laser (VFEL) are investigated by methods of mathematical modelling using computer code VOLC. It was demonstrated the possibility of excitation of quasiperiodic oscillations not far from threshold values of electron beam current density and VFEL resonator length. It was investigated sensibility of numerical solution to initial conditions for different VFEL regimes of operation. Parametric maps with respect to electron beam current and detuning from synchronism condition present complicated root to chaos with windows of periodicity in VFEL. Investigation of chaotic lasing dynamics in VFEL is important in the light of experimental development of VFEL in Research Institute for Nuclear Problems.

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