| CPC H01J 37/26 (2013.01) [H01J 37/222 (2013.01); H01J 37/28 (2013.01); H01J 37/3005 (2013.01); H01J 37/304 (2013.01); H01J 37/3045 (2013.01); H01J 37/3056 (2013.01); G06T 2207/10061 (2013.01); H01J 2237/226 (2013.01); H01J 2237/2811 (2013.01); H01J 2237/3174 (2013.01); H01J 2237/31749 (2013.01)] | 42 Claims |

|
1. A method for removing material from a sample to provide a section of the sample in a charged particle beam (CPB) system having at least one charged particle beam each being controllable in position, comprising:
(a) providing a sample having x, y and z dimensions with first and second fiducials each having ends electronically detectable proximate to a front cross-section surface of the sample defined by the x-y plane and each extending from the front cross-section surface in a direction having the z-dimension component at known angles relative to the x-y surface;
(b) setting a target distance m from the front cross-section surface in the z-dimension, where m is a real number;
(c) setting a slice distance of n, where n<m and n is a real number;
(d) scanning the cross-section surface to obtain a slice image thereof by an imaging system;
(e) iteratively executing the steps of
i. exposing a subsequent cross-section surface defined by the x-y plane with a material removal tool to the slice distance of n, and where an x dimension distance between ends of the first and second fiducials exposed in each subsequent cross-sectioned surface changes along the z-dimension; and
ii. scanning the subsequent cross-section surface to obtain a subsequent slice image thereof by the imaging system, until a selected number of slice images have been obtained,
(f) electronically calculating an actual distance in the z-dimension between a first and last slice image of the selected number of slice images based on a change in the x dimension distance and the angles;
(g) aggregating actual distances and stopping the iterative execution of step (e) when the aggregated actual distances is approximately the target distance m, and when the aggregated actual distances is not approximately the target distance m,
automatically updating slice distance n by adjusting parameters to advance the material removal tool in the z dimension for exposing a new cross-section surface at a distance in the z dimension that is closer to the slice distance n, based on a difference between the actual distance and an aggregated distance of slices corresponding to the selected number of slice images each having the previous slice distance n; and
(h) updating the selected number of slice images and returning to step (e).
|