An Ultrahigh Resolution Specimen Holder with Large Tilt Range for the Transmission Electron Microscope

Transmission electron microscopy (TEM) is the primary methodology for characterizing the internal structure of materials at the nanometer to sub-Angstrom scale. In the TEM, image formation results from the scattering of an incident electron wave by the atoms inside the crystal, and results in the formation of an image via either amplitude or phase contrast. In each case, the details of the scattering processes are highly dependent on the precise angle between the incident beam and the sample. However, the currently available mechanisms for in situ sample tilting is limited in resolution and accuracy by the frictional interfaces in the mechanism and the presence of large amounts of backlash. These mechanisms also have limited goniometer tilt range because of the width and thickness of the mechanism. This project will develop a specimen holder that will provide microscopists with unprecedented access to the crystallographic planes of their specimen, making it easy to achieve precise orientations. In Phase I, we developed and tested new hardware that provided both high resolution and high range in pole pieces suitable for materials science work. In Phase II, we will refine and extensively test this design, as well as improve the interface to the microscope. Commercial Applications and other Benefits as described by the awardee: By providing high resolution, range, and stability, the new specimen holder should allow researchers in nanotechnology and materials science to fully exploit recent gains in resolution in advanced electron microscopes. The images produced by these microscopes are used routinely to guide discoveries in nanoscience and materials development, and form a critical component in the semiconductor failure analysis market.