Preparation of oxide superconductor specimens for TEM examination

We have investigated a wide variety of oxide superconductors and report here on a number of techniques that can be effectively used to prepare transmission electron microscopy (TEM) specimens from these materials. Crushing, cleaving, ion milling, ultramicrotomy, and jet polishing all were successfully utilized, and details of each technique, as well as equipment used, are described. Selection among these methods depends both on the starting form of the material and the information required. Ion milling and crushing generally give the best results and have the widest applicability in our particular work, while crushing and cleaving involve the least equipment cost. In some cases, particularly with ion milling and jet polishing, small variations in the details of preparation have a dramatic effect on the success rate. We have found it to be a great advantage that the same techniques can be applied in a similar manner to a whole range of oxide materials, even (with some refinements and special precautions) to those that are extremely oxygen or moisture sensitive.