We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.
Nobody downloaded yet

Scanning Electron Microscopy - Coursework Example

Comments (1) Cite this document
The study "Scanning Electron Microscopy" presents the selection and comparison of a SE and BSE image taken from the same region of a sample. The researcher of this study aims to analyze the relative merits of the BSE image, x-ray maps and spot mode spectra…
Download full paper
Scanning Electron Microscopy
Read TextPreview

Extract of sample
Scanning Electron Microscopy

Download file to see previous pages... Secondary Electron images (SE) Vs. Backscattered Electron images (BSE)Secondary electron images are formed from the low energy electrons that are formed near the surface of the sample (Johnson). The brightness is affected by the surface topology of the specimen. For backscattered electron images, higher energy electrons formed deeper in the material are used to form the image. The result of these images is less contrast due to surface topology and more contrast due to different chemical composition (Johnson). This explains the 3D nature of the SE image in comparison to the flat BSE image, and the higher contrast of the BSE image in comparison to the SE image.Secondary electrons have lower energy compared to backscattered electrons, and so, they interact with the outer regions of the specimen by inelastic collisions. Therefore, only the surface topology of the specimen is clearly defined. This is the reason why the fibers in the SE looked clumped.The contrast in the BSE image is because of the production of backscatter electrons produced due to collisions of high energy electrons of the specimen. Parts of the specimen with higher atomic number cause higher backscatter than the lighter atomic number elements, resulting in a greater contrast, enabling a better study of the chemical composition of the specimen.The greater edge highlight in the SE image is because raised surfaces yield more secondary electrons....
The greater edge highlight in the SE image is because raised surfaces yield more secondary electrons. Images of a tilted TEM grid are provided showing a large difference in depth of field (file names DOF 1, 2, 3). 3 Calculate the depth of field from the images provided. Explain how you arrived at your answer. Compare SEM figures with the depth of field that would be available from an optical microscope for the same magnification. Large depth of field is one of the most important characteristics of SEM. The sharpness of the images recorded at low magnifications depends more on depth of field available than on small beam size (Lyman 1990). We know that depth of field, Where, d = minimum resolution of SEM W = Working distance D = aperture size Accordingly, the depth of field from the given images is computed as follows: Taking the following assumptions, d = minimum resolution of SEM= 3.5 nm = 3.5 ?10-9 m W = Working distance = as given in image in mm ?10-3 m D = aperture size= 200?m = 200?10-6 m Depth of field for first image with WD=13.0 mm= 13.0?10-3 m = 0.455?10-6 m = 4.55?10-7 m Depth of field for second image with WD=14.3 mm= 14.3?10-3 m =0.5005?10-6 m = 5?10-7 m Depth of field for second image with WD=44.3 mm= 44.3?10-3 m =1.55?10-6 m Comparison of SEM figures with the depth of field that would be available from an optical microscope for the same magnification The depth of field of SEM can be as great as 300 times that of the optical microscope. At low magnifications, below 300 to 400X, the image formed by the SEM is inferior to that of the optical microscope (Abbaschian et al 2008). At the same magnification, the depth of field that would be ...Download file to see next pagesRead More
Cite this document
  • APA
  • MLA
(“Scanning Electron Microscopy Coursework Example | Topics and Well Written Essays - 2500 words”, n.d.)
Retrieved de https://studentshare.org/physics/1390166-scanning-electron-microscopy
(Scanning Electron Microscopy Coursework Example | Topics and Well Written Essays - 2500 Words)
“Scanning Electron Microscopy Coursework Example | Topics and Well Written Essays - 2500 Words”, n.d. https://studentshare.org/physics/1390166-scanning-electron-microscopy.
  • Cited: 0 times
Comments (1)
Click to create a comment or rate a document
modestoklein added comment 2 months ago
Student rated this paper as
I never thought 3750 words essay could be written in such a free manner. I loved the background of this essay. Will definitely use it for my own work!
Electron Microscopy

Images in TEM are obtained by focusing an electron beam on the specimen. The electrons are absorbed, transmitted, scattered or backscattered. Depending on the kind of image required by the operator, either the transmitted electrons (called direct beam) or the scattered electrons (called diffracted beam) is selected. 

21 Pages(5000 words)Coursework
Use of Electron Microscopy for Investigating Teeth Erosion
From this paper, it is clear that TEM has a large number of applications in innumerable fields ranging from life sciences to material science. TEM has proved to be a priceless tool for studying the ultrastructure of metals (Egerton 2005, 14). In life sciences, it is used for studying bacteria, viruses, and tissues of plants and animals.
5 Pages(1500 words)Essay
Observe particles by using Scanning Electron Microscope (SEM), Energy Dispersive X-ray SEM and Transmission Electron Microscopy
SEM images were used to carry out size distribution analysis of the powder particles using a software package CARNOY. BSE image of the powder particles was taken and EDS was performed to get chemical information about bright particles in the powder sample.
6 Pages(1500 words)Essay
Electron Microscopy
This essay analyzes that spherical aberration also occurs in the Electron Microscopes when electrons passing through the side of the lens are refracted greater than those passing along the axis.2 (Lam, 2009); while Diffractive aberrations are brought about by the deviations from geometrical optics caused by the wave nature of light.
4 Pages(750 words)Coursework
Low Voltage Scanning Electron Microscopy

The author states that low-voltage electron microscopes (LVEM) have proven to be effective in comparison to High-voltage electron microscopes (HVEM). Both types of microscopes work on the same principles, but the significant different between them results from the effect of electron acceleration voltage variation.

7 Pages(1500 words)Research Paper
Use of the scanning electron microscopy in the food industry
Scanning electron microscopy (SEM), as well as other techniques such as energy dispersive spectroscopy (EDS) is an effective tool used for the identification and characterization of particulate contamination and foreign body contamination of food.
6 Pages(1500 words)Research Paper
Grant proposal+SOP
2. Please type throughout. Print one copy, sign, and send original plus 3 double sided photocopies to YCR, 39 East Parade, Harrogate HG1 5LQ. 3. Email a copy to science@ycr.org.uk – remember to save the form with a meaningful filename. 4. Before completing this form please read the specific Awards Information, Award Conditions and Policies for Awards.
7 Pages(1750 words)Coursework
Nature of an electron
QUESTION ONE Photoelectric effect Photoelectric effect is the process by which electrons are emitted from the surface of a photosensitive material when hit by light incidents. The intensity of the light energy determines the kinetic energy of the produced photoelectrons.
9 Pages(2250 words)Coursework
Besides, attenuation of the primary electron beam will also be lesser. This will lead to better image quality and better microanalytical capability of a TEM. Besides, minimizing molecule – electron beam interaction, better vacuum level
3 Pages(750 words)Coursework
Physics (Electron Physics and X-ray Tomography)
In the process, it gives off energy in form of X-rays. In the figure below, x-rays penetrates an atom and collides with an electron in the K-shell, strongly bound electrons, phenomena known as photon emission1. The energy of the incoming rays must be
7 Pages(1750 words)Coursework
Let us find you another Coursework on topic Scanning Electron Microscopy for FREE!
Contact us:
Contact Us Now
FREE Mobile Apps:
  • About StudentShare
  • Testimonials
  • FAQ
  • Blog
  • Free Essays
  • New Essays
  • Essays
  • The Newest Essay Topics
  • Index samples by all dates
Join us:
Contact Us