Zeiss Gemini 300 FESEM

FOM Name:  SEM Zeiss/Gemini 300
Contact: Julie Morasch (morasch@wisc.edu, 608-262-3613)
Location: MSE Room 173


The Zeiss GeminiSEM 300 is a high-performance variable pressure Scanning Electron Microscope (SEM) equipped with a Schottky type field emission gun, various detectors (in-lens and Everhart-Thornley type secondary electron detectors, as well as a variable pressure secondary electron detector, an in-lens back scattered electron detector, and multi-quadrant solid state back-scattered electron detector). This system also has Oxford EDS and EBSD detectors.  This system has an oil free vacuum system to maintain hydrocarbon free imaging.   To ensure the clean environment, the SEM is equipped with an in situ reactive oxygen sample cleaning system. Atlas 5 is available on the Gemini 300 for large scale mapping.

This is an accordion element with a series of buttons that open and close related content panels.


  • Accelerating voltage: 50 V to 30 kV.
  • Image resolution: 0.7 nm at 15 kV, 1.2 nm at 1 kV.
  • In column (In-lens) secondary electron detector: high resolution surface detail; used up to 20 kV.
  • In column (In-lens) back-scattered electron detector (low accelerating voltage back-scattered imaging).
  • Chamber-mount (Everhart-Thornley) secondary electron detector: best view of three dimensional morphology; works at all accelerating voltages.
  • Chamber-mount variable pressure secondary electron detector.
  • Chamber-mount angular resolved solid-state multi-quadrant back-scattered electron detector.
  • EDS/EBSD: Oxford Aztec
  • Atlas 5 software for mapping
  • Sample stage: motorized 130 mm X/Y travel, 50 mm Z travel, -4° to 70° tilt, 360 ° rotation.
  • In situ sample cleaning system.
  • Available ancillary equipement: Leica ACE 600 coating system; Leica TIC3X Triple ION Beam Miller for large sample cross-sectioning and surface polishing for EBSD.