To reduce artifacts in a surface exposed by a focused ion beam for viewing, a trench is milled next to the region of interest, and the trench is filled to create a bulkhead. The ion beam is directed through the bulkhead to expose a portion of the region of interest for viewing. The trench is filled, for example, by charged particle beam-induced deposition. The trench is typically milled and filled from the top down, and then the ion beam is angled with respect to the sample surface to expose the region of interest.