Patent ID: 9733164
Date: 2017-08-15
CPC Classifications: G01N,H01J

Claim:
1. A method of creating a sample lamella for observation by a transmission electron microscope, the method comprising forming a first substantially planar face of the sample lamella by: directing a first beam at a first surface of a substrate positioned on a sample stage to remove material from a first location in the substrate, the first beam being offset from a normal to the first surface by a first nonzero curtaining angle; sweeping the first beam in a plane that is perpendicular to the first surface to mill one or more first initial cuts in the substrate, the first initial cuts exposing a second surface that is tapered but substantially perpendicular to the first surface; determining a nonzero rotation angle according to the equation: where θ rotating the substrate without tilting the sample stage with respect to the first beam and through the nonzero rotation angle about an axis other than an axis that is normal to the first beam or parallel to the first beam; directing the first beam at the second surface to remove additional material from the substrate without changing the first nonzero curtaining angle; and scanning the first beam in a pattern across the second surface to mill one or more first finishing cuts in the substrate, the one or more first finishing cuts substantially removing the taper of the second surface, wherein rotating the substrate occurs after milling the one or more first initial cuts and before milling the one or more first finishing cuts.