Specimen Interaction Volume

Specimen Interaction Volume

The volume inside the specimen in which interactions occur while being struck with an electron beam. This volume depends on the following factors:

  • Atomic number of the material being examined; higher atomic number materials absorb or stop more electrons and so have a smaller interaction volume
  • Accelerating voltage being used; higher voltages penetrate farther into the sample and generate larger interaction volumes
  • Angle of incidence for the electron beam; the greater the angle (further from normal) the smaller the volume

Below is an example of a typical Interaction volume for:

  • Specimen is predominately Atomic number 28
  • Accelerating Voltage is 20 kV
  • 0 degrees tilt, incident beam is normal to specimen surface

noting the approximate maximum sampling depths for the various interactions. See Specimen Interactions for details on specific interactions listed.

specimen interaction volume