Scanning Electron Microscope

Scanning Electron Microscope and X-Ray Detector

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INCA x-act X-Ray Detector

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SCANNING ELECTRON MICROSCOPE

 

JEOL JSM-6390LV/LGS Scanning Electron Microscope

  • Magnification of the JEOL JSM-6390LV/LGS is on the order of 300,000x magnification, where fine details of specimens can be observed
  • The JSM-6390 is a high-performance, low cost, scanning electron microscope with a high resolution of 3.0nm
  • The customizable GUI interface allows the instrument to be intuitively operated, and Smile ShotTM software ensures optimum operation settings
  • The JSM-6390 specimen chamber can accomodate up to 6-inches in diameter
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  • Standard automated features include auto focus/auto stignator, auto gun (saturation, bias, and allignment), and automatic contrast and brightness
  • The JSM-6390 is used in many and varied applications

JEOL JSM-6390LV/LGS SEM

 

JEOL JSM-6390LV/LGS Specifications

Magnification 5 to 300,000x
kV 0.5 to 30kV
SEI @ 30kV 3nm
SEI @ 1kV 15nm
BEI @ 30kV 4nm
Stage X, Y, Z 80mm x 40mm x 48mm
EDS Geometry 35° TOA @ 10mm

What is a Scanning Electron Microscope?

The SEM is a type of electron microscope that creates various images by focusing a high energy beam of electrons onto the surface of a sample and detecting signals from the interaction of the incident electrons with the sample’s surface.

The primry function of the SEM is an IMAGING platform that can image using secondary electrons (SE) or backscattered electrons (BSE).

When coupled with X-ray detectors, we can determine COMPOSITIONS of materials.

 

Scanning Electron Microscope: Main Components

componentsVacuum system

  • coherent electron beam

Electron Gun

  • Tungsten filament
  • Accelerating voltage

Lens system

  • Electromagnetic lenses

Scan Unit

  • Imaging

Detector Units

  • BSE
  • SE
  • X-Ray (EDS/WDS)

 

 

Scanning Electron Microscope: Signals

Electrons react with specimen to produce different signals:

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  1. Secondary Electrons (SE)
  2. Backscattered Electrons (BSE)
  3. Characteristic X-Rays (EDS/WDS)

How Does a SEM Work?

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  • An electron gun generates an electron beam
  • The electron beam is focused through a set of electromagnetic lenses
  • Imaging occurs through the scan unit
  • Various detectors acquire the various signals to display an image

 

Magnification

Magnification is a function of the raster area.

MAGNIFICATION = Size of Raster on Viewing Screen/Size of Raster on Specimen

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Sample Preparation

Various sample preparation methods and mounting methods are used for SEM imaging and analysis including adhesion of dry samples to metal stubs, epoxy-embedded grain mounts of particales, polished thin sections, biological samples, and even frozen samples requiring cooling stages.

Stub Mounts

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Cryo Stub

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Thin Section

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Grain Mount

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Cryo Stage (Liquid Nitrogen Cooling Holder)

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Sample Holders

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Conductive Coating

This Facility houses a Denton Vacuum Desk IV Sputter Coater and carbon coating accessories.

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