A Mechanical Method for Preparing TEM Samples from Brittle Films on Compliant Substrates

Abstract

Abstract Preparing transmission electron microscopy (TEM) samples from thin films is technically challenging and traditional preparation routes can sometimes introduce unacceptable artefacts or even prove impossible. A novel method of preparing plan view TEM samples from thin films by a purely mechanical method is assessed. Two examples of films prepared by this route are briefly presented, a Cr film on PET and an amorphous AlxOy film on Cu. The application of this method allows for TEM analysis of the Cr film without the problems associated with a polymer such as PET disintegrating under the electron beam. For the AlxOy films it is demonstrated that this purely mechanical preparation prevents crystallisation of the film resulting from conventional ion milling preparation routes. The technique also allows for an upper bound of thickness approximation for these films.