Variable Pressure Scanning Electron Microscope

Scanning Electron Microscopy (SEM) is a method for high-resolution imaging of surfaces. The SEM uses electrons for imaging, much as a light microscope uses visible light. The advantages of SEM over light microscopy include much higher magnification (>100,000 x) and greater depth of field, up to 100 times that of light microscopy. In variable-pressure SEM, imaging can be performed directly on a nonconductive sample when the chamber pressure is maintained at a level where most of the electrons reach the sample surface, whilst there are enough gas molecules to ionize and neutralize charging. Variable pressure SEM is also valuable for examination of samples that are not compatible with high vacuum.

SEM, Zeiss-EVO10

Analytical Information:

- Secondary Electron Imaging: This mode provides high-resolution imaging of fine surface morphology

- Backscatter Electron Imaging: This mode provides image contrast as a function of elemental composition, as well as surface topography

Technical Specifications, Zeiss EVO-MA 10 Scanning Electron Microscope:

- VP-SEM variable pressure operation (10-400 Pa)

- Resolution: 2nm @ 30kV (SE), 15 nm @ 1kV (SE), 4.5 nm @ 30 kV (BSD, VP mode);

- High-brightness LaB6 source

- Motorized 5-axes stage

-Magnification: 7 – 500,000x

- Available detectors:

  • Multi segment diode (BSD)
  • Everhart-Thornley Secondary Electron Detector (ETSE)
  • Variable Pressure Secondary Electron Detector (VPSE)

To access images related to this process, please click on its respective “Sample Images” tab in the drop down menu above. To download these images, along with brief explanations, click here: variable scanning electron microscope