Arecent discussion on the Microscopy Listserver on the subject of microtoming Si reminded many of us of this decades-old issue. Silicon is one of the easiest materials to prepare for TEM analysis with dozens of protocols available including chemical etching, electropolishing, mechanical polishing with and without ion milling, microcleaving, and the use of a focused ion beam instrument. The time involved in Si preparation can range from minutes to a few hours. Things become more complex if it is desired to prepare a Si semiconductor device with high specimen preparation spatial resolution i.e. prepping a prespecified, very small, structure.

Now and then a technologist, often times in the biological sciences, is asked to prepare a Si TEM specimen and wonders if Si can be microtomed. The results are almost always a pile of Si dust and frequently a damaged diamond knife.