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High resolution observation using the Super Hybrid Lens (SHL)

The objective lens is a Super Hybrid Lens (SHL), which consists of an electrostatic magnetic field overlapped with an electrostatic electric field. Reducing the chromatic and spherical aberrations improves the resolution, especially at low accelerating voltages. The SHL does not exert magnetic field influences on the specimen, so observations of magnetic materials and EBSD analysis can be performed without difficulty.
 

Energy selection at low accelerating voltages

An energy filter is mounted directly below the upper electron detector (UED), so energy selection is possible.  Secondary electrons and backscattered electrons can be selected accurately, even at low accelerating voltages, allowing composition observation of the top surface of the specimen using a backscattered electron image at low accelerating voltages.
 

Top surface imaging using Gentle Beam

By applying a bias voltage to the specimen (GB), the speed of the incident electrons is reduced and the speed of the released electrons is increased. This allows high-resolution images with a good signal-to-noise ratio to be acquired even with low specimen exposure energies. If GB mode is used, which allows a higher bias voltage to be applied, even higher-resolution observations can be made even at specimen exposure energies of just a few tens of eV.
 

Acquisition of all information using multiple detectors

The JSM-7800F incorporates 4 types of detectors, including an upper electron detector (UED), upper secondary electron detector (USD), backscattered electron detector (BED), and a lower electron detector (LED). For the UED, the secondary electron and backscattered electron dose can be changed according to the filter voltage, making it possible to select the electron energy. The USD detects the low-energy electrons that bounce off the filter. With the BED, channeling contrast can be clearly observed by detecting the low-angle backscattered electrons. The LED enables acquisition of images with a 3-dimensional appearance, including the surface roughness information from the illumination effects.
 

Application examples

• Observation at low accelerating voltage
  By the Gentle Beam (GB) method, observation from at the specimen exposure energy of 10 eV is possible. The surface of graphene sheet the thickness of just one atom is observable with the specimen exposure energy being set 80 eV.
  
  Specimen: Graphene ( specimen exposure energies: 80eV)
• Energy selection
  With BE image (left) and SE image (right) simultaneously being obtained by UED and USD, precise interpretation of images is possible.  Segregation between gold particles and TiO₂, not obvious by SE image which contrast depends mainly on the topography, becomes clear by BE image, where gold particles become brighter because of its higher mean atomic number.

  BE image	SE image
  Spesimen: gold supported TiO2 catalyst (2kV)

• Observation using GBSH
  The GBSH method applies a negative voltage to a specimen.  With the aberration being reduced, high resolution images are produced.  Clear observation of mesoporous silica is realized.
  
  Specimen:  Mesoporous silica (specimen exposure energy: 1keV)
• Observation of  magnetic materials
  SHL does not form magnetic field around a specimen.  Threfore high resolution observation of magnetic materials, and even at low specimen exposure energies, can be performed without difficulty.
  
  Specimen: Magnetite nano particles (specimen exposure energy: 1keV)
• EBSD can be performed comfortably, since SHL does not exert magnetic field influences on the specimen.  IPF Map produces high precision crystal orientation analysis.

  Number of points: 118585 Dimensions: X Max: 80.00 microns, Y Max: 79.89 microns Step: 0.25 microns Phases: Nd2Fe14B

  Example of EBSD pattern

   

  ND

  TD

  RD