Practical Electron Microscopy and Database

In STEM measurements, the electronic noise or interference by any stray fields in the environment can superimpose on the ramping current in the scanning coils when STEM images are generated by rastering the electron beam on specimens. The high frequency fluctuation leads ‘tearing’ noise in the images, while the medium- and low-frequency noises induce distortion of the images. All those noise and interference especially affect the precision of spatial coordinates of the recorded atomic features.

In many cases, the STEM image can be low-pass filtered to remove scan noise.