scholarly journals Continuum models of focused electron beam induced processing

2015 ◽  
Vol 6 ◽  
pp. 1518-1540 ◽  
Author(s):  
Milos Toth ◽  
Charlene Lobo ◽  
Vinzenz Friedli ◽  
Aleksandra Szkudlarek ◽  
Ivo Utke
Keyword(s):  
Electron Beam ◽  
Substrate Surface ◽  
Input Parameter ◽  
Reaction Pathways ◽  
Continuum Models ◽  
Direct Write ◽  
Reaction Products ◽  
Wide Range ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

Focused electron beam induced processing (FEBIP) is a suite of direct-write, high resolution techniques that enable fabrication and editing of nanostructured materials inside scanning electron microscopes and other focused electron beam (FEB) systems. Here we detail continuum techniques that are used to model FEBIP, and release software that can be used to simulate a wide range of processes reported in the FEBIP literature. These include: (i) etching and deposition performed using precursors that interact with a surface through physisorption and activated chemisorption, (ii) gas mixtures used to perform simultaneous focused electron beam induced etching and deposition (FEBIE and FEBID), and (iii) etch processes that proceed through multiple reaction pathways and generate a number of reaction products at the substrate surface. We also review and release software for Monte Carlo modeling of the precursor gas flux which is needed as an input parameter for continuum FEBIP models.

High-resolution observation of sintered alumina (Al2O3) using the specimen-heated and electron-beam-induced conductivity method in a UHR-SEM

1994 ◽  
Vol 52 ◽  
pp. 1046-1047
Author(s):  
K. Ogura ◽  
T. Suzuki ◽  
C. Nielsen
Keyword(s):  
Electron Beam ◽  
High Resolution ◽  
Specimen Preparation ◽  
Conductivity Method ◽  
Fine Grain ◽  
Grain Structures ◽  
Resolution Observation ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Charging Effect

In spite of the complicated specimen preparation, Transmission Electron Microscopes (TEM) have traditionally been used for the investigation of the fine grain structures of sintered ceramics. Scanning Electron Microscopes (SEM) have not been used much for the same purpose as TEM because of poor results caused by the specimen charging effect, and also the lack of sufficient resolution. Here, we are presenting a successful result of high resolution imaging of sintered alumina (pure Al2O3) using the Specimen Heated and Electron Beam Induced Conductivity (SHEBIC) method, which we recently reported, in an ultrahigh resolution SEM (UHR-SEM). The JSM-6000F, equipped with a Field Emission Gun (FEG) and an in-lens specimen position, was used for this application.After sintered Al2O3 was sliced into a piece approximately 0.5 mm in thickness, one side was mechanically polished to get a shiny plane for the observation. When the observation was started at 20 kV, an enormous charging effect occured, and it was impossible to obtain a clear Secondary Electron (SE) image (Fig.1).

Analysis of Interesting Materials in the Environmental SEM: You Put What in Your Microscope?

2001 ◽  
Vol 7 (S2) ◽  
pp. 776-777
Author(s):  
John F. Mansfield
Keyword(s):  
Electron Microscope ◽  
Chemical Engineering ◽  
Materials Science ◽  
Variable Pressure ◽  
Environmental Scanning ◽  
Specimen Preparation ◽  
Wide Range ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

The environmental scanning electron microscope (ESEM™) and variable pressure electron microscope (VPSEM) have become accepted tools in the contemporary electron microscopy facility. Their flexibility and their ability to image almost any sample with little, and often no, specimen preparation has proved so attractive that each manufacturer of scanning electron microscopes now markets a low vacuum model.The University of Michigan Electron Microbeam Analysis Laboratory (EMAL) operates two variable pressure instruments, an ElectroScan E3 ESEM and a Hitachi S3200N VPSEM. The E3 ESEM was acquired in the early 1990s with funding from the Amoco Foundation and it has been used to examine an extremely wide variety of different materials. Since EMAL serves the entire university community, and offers support to neighboring institutions and local industry, the types of materials examined span a wide range. There are users from Materials Science & Engineering, Chemical Engineering, Nuclear Engineering, Electrical Engineering, Physics, Chemistry, Geology, Biology, Biophysics, Pharmacy and Pharmacology.

Things That Go “Bump” in the VPSEM - and How We Image with Them

2001 ◽  
Vol 7 (S2) ◽  
pp. 772-773
Author(s):  
Brendan J Griffin
Keyword(s):  
Secondary Electron ◽  
Full Range ◽  
High Vacuum ◽  
Electron Interaction ◽  
Variable Pressure ◽  
Imaging Model ◽  
Wide Range ◽  
Electron Microscopes ◽  
Electron Imaging ◽  
Scanning Electron Microscopes

Variable pressure scanning electron microscopes (VPSEM) differ from conventional SEM by operating at pressures ranging from the ‘high vacuum’ SEM levels of 10-6 torr up to typically around 2 torr. The environmental SEM or ESEM is a commercial variant which employs an unique multistage pressure-limiting aperture (PLA) system to attain specimen chamber operating pressures of up to 50 torr. Early instruments used air or argon as the imaging gas but more commonly today water vapour is used. A wide range of gases have been employed, including potentially explosive hydrogen-methane mixtures. The choice of gas is operator-based and can be varied during the imaging session.Early VPESM were restricted to backscattered electron imaging (BSE) until the development of the gaseous secondary electron detector in the ESEM. Gaseous secondary electron detectors are now available for all models of VPSEM and together with compatible cathodoluminescence and EDS XRay detectors, the full range of SEM-based imaging options is present.The principal distinguishing feature of VPSEM is, of course, that samples can be examined uncoated. Gas-electron interaction generates a positive ion supply that can minimise conventional charging artefacts, in a simple imaging model.

scholarly journals Low Vacuum SEMs: Latest Generation Technologies and Applications

2007 ◽  
Vol 15 (4) ◽  
pp. 20-25
Author(s):  
William Neijssen ◽  
Ben Lich ◽  
Pete Carleson
Keyword(s):  
Focused Ion Beam ◽  
Electron Backscatter Diffraction ◽  
Ion Beam ◽  
High Vacuum ◽  
Ease Of Use ◽  
Wide Range ◽  
Sample Chamber ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Backscatter Diffraction

Since becoming popular more than a decade ago, low vacuum scanning electron microscopes (SEM) have continued to evolve. The latest systems offer uncompromised performance over an unprecedented range of sample chamber vacuum conditions. Instruments are now available that provide near-nanometer resolution in all vacuum modes and the ability to operate at pressures as high as 4000 Pascals (~30 Torr). Low vacuum operation eliminates much of the sample preparation required for conventional (high vacuum) SEM. Insulating samples can be imaged without conductive coatings. Wet, dirty, outgassing samples can be examined without drying and fixing. Systems can also be configured with a wide range of ancillary capabilities for imaging, analysis, and sample manipulation, including advanced secondary, backscattered, and transmitted electron detection, X-ray spectrometry, electron backscatter diffraction, and focused ion beam (FIB) manipulation. The current generation of systems combine speed, flexibility, repeatability, and ease of use, making them the ideal solution for any laboratory that must satisfy a wide range of imaging and analytical demands.

Dynamic Focusing Techniques for Enhancing SEM Images

1972 ◽  
Vol 30 ◽  
pp. 378-379
Author(s):  
Nelson C. Yew
Keyword(s):  
Electron Beam ◽  
Spherical Surface ◽  
Sem Images ◽  
Condenser Lens ◽  
Sem Image ◽  
Collector System ◽  
Electron Collection ◽  
Effective Depth ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

There are two major areas where Dynamic Focusing techniques can be used to enhance SEM image qualify and micrograph information content. When used in conjunction with the final condenser lens in the electron-optical column, it increases the effective depth of focus associated with an inclined specimen in the SEM. When used with an ultra-high resolution recording cathode ray tube it provides exceptional corner-to-corner sharpness on the micrograph.Most commercial scanning electron microscopes use a tilted specimen positioned close to the final condenser lens with the secondary electron collector system located in the tilting direction to facilitate efficient electron collection. electron beam pivoting through the center of the principle plane of this lens to minimize distortion and off-axis aberration problems. As a result, the final electron beam is truly focused only along a portion of the spherical surface with its center located at the pivoting point.

Synthesis of Hard-Melting Carbide, Nitrite and Intermetallic Phases with Surface Electron-Beam Microallоying

2016 ◽  
Vol 876 ◽  
pp. 25-35 ◽  
Author(s):  
Mariuch Jenek ◽  
Sergey Voldemarovich Fedorov ◽  
Min Htet Swe
Keyword(s):  
Thin Film ◽  
Electron Beam ◽  
Chemical Reactions ◽  
Intermetallic Phases ◽  
Experimental Results ◽  
Reaction Products ◽  
Surface Electron ◽  
Wide Range ◽  
New Phase

The experimental results prove the ability to produce layers modified by microalloying with electron-beam technology using wide range of materials. Such layers were produced due to initiating exothermic chemical reactions between the base and the thin film covered the base. This resulted in finding new phase compounds in reaction products.

Advances in Scanning Electron Microscopy

MRS Bulletin ◽  
1991 ◽  
Vol 16 (3) ◽  
pp. 41-45 ◽  
Author(s):  
K. Sujata ◽  
Hamlin M. Jennings
Keyword(s):  
Electron Beam ◽  
X Rays ◽  
Backscattered Electrons ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Television Image ◽  
Focused Beam ◽  
Scanning Electron

Scanning electron microscopes offer several unique advantages and they have evolved into complex integrated instruments that often incorporate several important accessories. Their principle advantage stems from the method of constructing an image from a highly focused electron beam that scans across the surface of a specimen. The beam generates backscattered electrons and excites secondary electrons and x-rays in a highly localized “spot.” These signals can be detected, and the results of the analysis are displayed as a specific intensity on a screen at a position that represents the position of the electron spot. As with a television image, after a given period, information about the entire field of view is displayed on the screen, resulting in a complete image. If the specimen is thin, the same type of information can be gathered from the transmitted electrons, and a scanning transmission image is thus constructed.The scanning electron microscope is highly versatile and widely used. The quality of the image is related to its resolution and contrast, which, in turn, depend on the diameter of the focused beam as well as its energy and current. Because electron lenses have inherently high aberrations, the usable aperture angles are much smaller than in a light microscope and, therefore, the electron beam remains focused over a relatively large distance, giving these instruments a very large depth of focus.Scanning electron microscopes are versatile in their ability to detect and analyze a lot of information. As a result, modern versions of these instruments are equipped with a number of detectors. Developments are sometimes related to placing the detectors in a geometrically attractive position close to the specimen.

Calibration of Scanning Electron Microscopes over a Wide Range of Magnifications

2017 ◽  
Vol 59 (12) ◽  
pp. 1245-1249 ◽  
Author(s):  
R. V. Kirtaev ◽  
A. Yu. Kuzin ◽  
V. G. Maslov ◽  
V. B. Mityukhlyaev ◽  
P. A. Todua ◽  
...  
Keyword(s):  
Wide Range ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron
Sign in / Sign up

Export Citation Format

Share Document