Aberration reduction in multipass electron microscopy
AssigneeThe Board of Trustees of the Leland Stanford Junior University
InventorsMark A. Kasevich, Stewart A. Koppell, Brannon Klopfer, Thomas Juffmann, Marian Mankos
Life of this patent
Estimating the term…
Abstract
Improved aberration correction in multipass electron microscopy is provided by having Fourier images of the sample (instead of real images) at the reflection planes of the resonator. The resulting −1 magnification of the sample reimaging can be compensated by appropriate sample placement or by adding compensating elements to the resonator. This enables simultaneous correction of lowest order chromatic and spherical aberration from the electron objective lenses. If real images of the sample are at the reflection planes of the resonator instead, only the lowest order chromatic aberration can be corrected.
Claims7
A multipass electron microscope comprising:
- an electron source;
- an electron resonator including two electron mirrors and configured to include a sample at a predetermined sample location, wherein the electron resonator is configured to provide multipass electron reimaging of the sample location such that diffraction planes of the sample location coincide with reflection planes of the electron mirrors;
- electron illumination optics configured to receive an electron beam from the electron source and to provide electron illumination to the electron resonator;
- electron projection optics configured to receive a multipass electron output from the electron resonator;
- an electron detector configured to receive the multipass electron output from the electron resonator and configured to provide an output image.
Dependencies are inferred from the claim text.