Transmission EBSD in the Scanning Electron Microscope

Abstract

We demonstrate in this article an exciting new method for obtaining electron Kikuchi diffraction patterns in transmission from thin specimens in a scanning electron microscope (SEM) fitted with a conventional electron backscattered diffraction (EBSD) detector. We have labeled the method transmission EBSD (t-EBSD) because it uses off-the-shelf commercial EBSD equipment to capture the diffraction patterns and also to differentiate it from transmission Kikuchi diffraction available in the transmission electron microscope (TEM). Lateral spatial resolution of less than 10 nm has been demonstrated for particles and better than 5 nm for orientation mapping of thin films. The only new requirement is a specimen holder that allows the transmitted electrons diffracted from an electron transparent sample to intersect the EBSD detector. We briefly outline our development of the technique, followed by descriptions of sample preparation techniques and operating conditions. We then present examples of t-EBSD patterns from a variety of specimens, including particles of diameter <10 nm, wires of diameter <80 nm, and films with thicknesses from ~5 nm to 300 nm. Finally, we discuss the phenomenon in the context of Monte Carlo electron scattering simulations.