Performance Evaluation of a Novel Type of Low-Energy Electron Microscope

1990 ◽  
Vol 48 (1) ◽  
pp. 354-355
Author(s):  
Bertholdand Senftinger ◽  
Helmut Liebl
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Field Strength ◽  
Numerical Aperture ◽  
Low Energy ◽  
Energy Electron ◽  
High Resolution Imaging ◽  
Lens System ◽  
Resolution Imaging ◽  
Low Energy Electron

During the last few years the investigation of clean and adsorbate-covered solid surfaces as well as thin-film growth and molecular dynamics have given rise to a constant demand for high-resolution imaging microscopy with reflected and diffracted low energy electrons as well as photo-electrons. A recent successful implementation of a UHV low-energy electron microscope by Bauer and Telieps encouraged us to construct such a low energy electron microscope (LEEM) for high-resolution imaging incorporating several novel design features, which is described more detailed elsewhere.The constraint of high field strength at the surface required to keep the aberrations caused by the accelerating field small and high UV photon intensity to get an improved signal-to-noise ratio for photoemission led to the design of a tetrode emission lens system capable of also focusing the UV light at the surface through an integrated Schwarzschild-type objective. Fig. 1 shows an axial section of the emission lens in the LEEM with sample (28) and part of the sample holder (29). The integrated mirror objective (50a, 50b) is used for visual in situ microscopic observation of the sample as well as for UV illumination. The electron optical components and the sample with accelerating field followed by an einzel lens form a tetrode system. In order to keep the field strength high, the sample is separated from the first element of the einzel lens by only 1.6 mm. With a numerical aperture of 0.5 for the Schwarzschild objective the orifice in the first element of the einzel lens has to be about 3.0 mm in diameter. Considering the much smaller distance to the sample one can expect intense distortions of the accelerating field in front of the sample. Because the achievable lateral resolution depends mainly on the quality of the first imaging step, careful investigation of the aberrations caused by the emission lens system had to be done in order to avoid sacrificing high lateral resolution for larger numerical aperture.

Electron Detectors For Microanalysis and High-Resolution Imaging

1985 ◽  
Vol 43 ◽  
pp. 162-165
Author(s):  
A. Christou
Keyword(s):  
High Resolution ◽  
Electron Probe ◽  
Low Energy ◽  
Energy Electron ◽  
High Resolution Imaging ◽  
Low Loss ◽  
Imaging Detectors ◽  
Resolution Imaging ◽  
Low Energy Electron

AbstractPresently available electron detectors are reviewed. These detectors are divided into electrostatic analyzers and magnetic or multi-channel analyzers. Imaging detectors also include the SLEEP (Scanning Low Energy Electron Probe) and the LLE detectors (Low Loss Electrons).

A New 200kv Energy Filter Field Emission Transmission Electron Microscope

1998 ◽  
Vol 4 (S2) ◽  
pp. 396-397
Author(s):  
T. Kaneyama ◽  
K. Tsuno ◽  
T. Honda ◽  
M. Kersker ◽  
K. Tsuda ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Field Emission ◽  
Transmission Electron Microscope ◽  
High Resolution Imaging ◽  
Elemental Mapping ◽  
Lens System ◽  
Transmission Electron ◽  
Wide Range ◽  
Resolution Imaging

In the field of biological and materials sciences, the importance of energy filter transmission electron microscope(EF-TEM) is increasing. Because it is a powerful instrument for contrast enhancement and obtaining elemental mapping images. We have developed a 200kV EF-TEM equipped with a fieldemission gun and in-column spectrometer. The new EF-TEM JEM-2010FEF inherits the performance in high resolution imaging and analysis from field emission TEM. The outer view is shown in Fig.l.Figure 2 shows the lens configuration of JEM-2010FEF. An in-column Q-type spectrometer is introduced within the imaging lens system. It was designed to have image distortion less than 1% and dispersion power 1.2p.m/eV for 200keV electrons. There is no need of compensating procedure of distortion. Imaging lens system consists of two objective lenses, three intermediate lenses and three projector lenses. The 8-stage imaging lens system enables wide range of imaging modes equal to conventional TEMs; energy spectroscopic image of magnification from ×200 to × 1,500,000, energy spectroscopic diffraction of camera length from 200mm to 2,000mm.

FIB Enhancement of Mechanically Polished Cross-sections

2019 ◽  
Author(s):  
Becky Holdford
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Scanning Electron Microscope ◽  
Cross Sections ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
High Resolution Imaging ◽  
Chemical Attack ◽  
Resolution Imaging ◽  
Scanning Electron

Abstract On mechanically polished cross-sections, getting a surface adequate for high-resolution imaging is sometimes beyond the analyst’s ability, due to material smearing, chipping, polishing media chemical attack, etc.. A method has been developed to enable the focused ion beam (FIB) to re-face the section block and achieve a surface that can be imaged at high resolution in the scanning electron microscope (SEM).

Double aberration correction in a low-energy electron microscope

2010 ◽  
Vol 110 (11) ◽  
pp. 1358-1361 ◽  
Author(s):  
Th. Schmidt ◽  
H. Marchetto ◽  
P.L. Lévesque ◽  
U. Groh ◽  
F. Maier ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Low Energy ◽  
Energy Electron ◽  
Aberration Correction ◽  
Low Energy Electron

Implementation and operation of a fiber-coupled CMOS detector in a low energy electron Microscope

2021 ◽  
Vol 221 ◽  
pp. 113180
Author(s):  
D. Janoschka ◽  
P. Dreher ◽  
A. Rödl ◽  
T. Franz ◽  
O. Schaff ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Low Energy ◽  
Energy Electron ◽  
Low Energy Electron
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