The continued reduction in the size of critical features in integrated circuits has resulted in the need to develop rapid, site-specific, sectioning techniques to enable efficient physical characterization of the structures of interest. We have implemented a mechanical polishing approach to achieve this objective with the additional goals of maximizing the number of targeted sites in a sample that can be analyzed, and minimizing physically destructive procedures, such as ion beam exposure. Precision sample preparation approaches have been under investigation for both transmission electron microscopy and scanning electron microscopy.
The mechanical specimen preparation approach used in this work is a variant of the well-known wedge polishing technique. Here we use a polishing tool that does not contact the grinding surface, thus allowing precise control of the wedge angle. Prior to sample preparation, the polishing tool head was precision aligned parallel to the platen.