SEM stands for scanning electron microscope. The SEM is a microscope that uses electrons instead of light to obtain an image. Since their development in the early 1950's, scanning electron microscopes have extended new areas of study in the medical and physical science communities. The SEM has allowed researchers of all ages and disciplines to examine a much bigger variety of specimens.
The JEOL Neoscope
How does Scanning Electron Microscopy work?
Electrons are generated by a power source and focused with a series magnetic lenses. The specimen is bombarded with the electrons and the diffraction that happens is collected by a detector that compiles an image of the sample.
The SEM has a large "depth of field", which allows more of a specimen to be in focus at one time.
The SEM also has much higher resolution, so closely spaced specimens can be magnified at much higher levels.
Because the SEM uses electromagnets rather than lenses, the researcher has much more control in the degree of magnification.
All of these advantages, as well as the actual strikingly clear images, make the scanning electron microscope one of the most useful instruments in research today.Additional Benefits: There are no expensive service contracts to support operation. It does not require as much electricity to support the instrument. Sample preparation is minimal. There is no high voltage or large magnetic fields. This instrument is super-user friendly and science teachers could easily use it (as well as art teachers).
Power of Imaging!
Use SEM to Zoom into a Computer Chip
Current Student Projects that would benefit from SEM
- Grace Benedict '23 Mycoremediation of microplastics
- Andrew Shen '23 Mechanical Engineering
- Chandler Gilbane '23 Cyanobacterial bacteriophages
- Cream Chinthammit '23 Tick-borne Diseases
- Addie Robertson '24 Bacteriophage Structural Analysis
- Kate Dorman '23 Red Tide and Microbial Signalling
- Margaret Culkins '23 Bioengineering and Stress Responses in Fruit Flies
- Danielle Page '23 Science of Kombucha
- Sabrina Dusek '23 Effects of Sunscreen on Tardigrades
- Fiona Dong '23 Parkinson's disease in Fruit Flies
- Taiya Wohr '23 Immunological NETS for the capture of mitochondria
- Emma Colley '23 Biofilm formation and microplastic aggregation
- Daphne Szakats '24 Vitiligo in the Drosophila Fruit Flies
- Logan Tao '24 Effects of Nitrous "whip-its" on Drosophila Fruit Fly.
Smart Coater: Coating of samples is required in the field of electron microscopy to enable or improve the imaging of samples. Creating a conductive layer of metal on the sample inhibits charging, reduces thermal damage, and improves the secondary electron signal required for topographic examination in the SEM. Fine carbon layers, being transparent to the electron beam but conductive, are needed for x-ray microanalysis, to support films on grids and back up replicas to be imaged in the TEM. The coating technique used depends on the resolution and application.