Method of performing tomographic imaging of a sample in a charged-particle microscope

摘要

A method of performing tomographic imaging of a sample in a charged-particle microscope, comprising the following steps:
- Providing a beam of charged particles that propagate along a particle-optical axis;
- Providing the sample on a sample holder that can be tilted relative to said beam;
- In an imaging step, directing the beam through the sample so as to form and capture an image of the sample at an image detector;
- Repeating this procedure at each of a series of sample tilts so as to acquire a corresponding set of images;
- Mathematically processing images from said set so as to construct a composite image of the sample,
whereby, in said imaging step, a sequence of component images is captured at a corresponding sequence of focus settings. This renders a 3D imaging cube rather than a 2D imaging sheet at a given sample tilt.