Chapter 6 - TSEM: A Review of Scanning Electron Microscopy in Transmission Mode and Its Applications

Abstract

Transmission electron imaging with standard scanning electron microscopes (SEMs) can be implemented simply by equipping the SEM with a readily available transmission detector. This mode, called STEM-in-SEM or simply TSEM, is a valuable technique that bridges the gap between SEM and high-voltage transmission electron microscopy. It combines the versatility of a SEM with the advantageous imaging modalities using transmitted electrons. TSEM can replace TEM or high-voltage STEM when atomic resolution is not needed, and it offers new imaging possibilities and applications due to its use of low-energy electrons. The basics of the TSEM technique are summarized. The configuration and the implementation of the transmission detector are introduced. The physics of electron scattering is briefly discussed, which is the basis of the different contrast mechanisms and can be simulated using Monte Carlo methods. Subsequently, we compare some aspects of TSEM with common electron microscopy techniques (TEM, STEM, and SEM). Various TSEM applications are presented, including traceable dimensional measurements, the characterization of different material classes, and special imaging modes.