Contamination of holey/lacey carbon films in STEM

Catriona M McGilvery; Angela E Goode; Milo S P Shaffer; David W McComb

doi:10.1016/j.micron.2011.10.026

Contamination of holey/lacey carbon films in STEM

Micron. 2012 Feb;43(2-3):450-5. doi: 10.1016/j.micron.2011.10.026. Epub 2011 Nov 4.

Authors

Catriona M McGilvery¹, Angela E Goode, Milo S P Shaffer, David W McComb

Affiliation

¹ Department of Materials, Imperial College London, Prince Consort Road, London, SW7 2BP, UK. catriona.mcgilvery@imperial.ac.uk

PMID: 22192979
DOI: 10.1016/j.micron.2011.10.026

Abstract

In many cases, the key to obtaining good TEM results is in the sample preparation itself. Even once a thin specimen is achieved, other factors determine how well the sample will behave in the microscope. One of the main hindrances to TEM and STEM-EELS analysis is the build up of carbon contamination on the sample under the electron beam. This process may occur due to the nature of the sample itself or the support grids or films on which the sample sits. Here, we investigate contamination on holey and lacey carbon films from three different suppliers. We find that all grids have a large amount of mobile hydrocarbon contamination on them, as well as other larger contaminant species on the surface. Even after a variety of cleaning routines, none of the films are clean enough for STEM-EELS experiments requiring long acquisition times.