Systems and methods for image enhancement for a multi-beam charged-particle inspection system

1. A method related to image enhancement for a multi-beam charged-particle system, the method comprising:

performing a frequency analysis of signal information representative of first and second images, wherein the first image is associated with a first beam of a set of beams and the second image is associated with a second beam of the set of beams;

detecting, based on the frequency analysis, disturbances in positioning of the first and second beams in relation to a sample;

obtaining an image of the sample using the signal information of the first and second beams; and

correcting the image of the sample based on the detected disturbances.

2. The method of claim 1 , wherein analysis of the signal information further comprises using coherent filtering to analyze the signal information.

3. The method of claim 2 , wherein using coherent filtering further comprises:

applying a linear operator to the signal information;

generating a filter based on properties of the first and second images; and

filtering the signal information by applying the filter to the signal information.

4. The method of claim 3 , wherein the filter is based on averaging power spectral densities of the first and second images.

5. The method of claim 3 , wherein the filter is based on determining a peak in the cross-spectral density for a combination of the first and second images.

6. The method of claim 5 , wherein the peak includes a plurality of peaks in the cross-spectral density for a combination of the first and second images.

7. The method of claim 3 , wherein the linear operator includes a Hilbert transform.

8. The method of claim 3 , wherein the linear operator includes a Fourier transform.

9. The method of claim 3 , wherein generating the filter further comprises analyzing signal information representing an entirety of each of the first and second images.

10. The method of claim 3 , wherein generating the filter further comprises analyzing signal information representing a scan line of the first and second images.

11. The method of claim 1 , wherein performing the frequency analysis further comprises:

determining a power spectral density based on the signal information; and

wherein correcting the image of the sample further comprises:

based on the power spectral density, filtering out a portion of the signal information that indicates dynamic disturbance or that indicates white noise.

12. The method of claim 1 , further comprising:

filtering white noise in the signal information with a white noise filter.

13. The method of claim 12 , wherein the white noise filter is based on a power spectral density of at least one of the first and second images.

14. The method of claim 1 , wherein the charged-particle system is one of a scanning electron microscope, a transmission electron microscope, or a scanning ion microscope.

15. A system for multi-beam scanning, comprising:

a detector including circuitry for detecting signal information representative of first and second images, wherein the first image is associated with a first beam of a set of beams and the second image is associated with a second beam of the set of beams;

a controller with at least one processor and a non-transitory computer readable medium comprising instructions that, when executed by the processor, cause the controller to:

perform a frequency analysis of the signal information;

detect, based on the frequency analysis, disturbances in positioning of the first and second beams in relation to a sample;

obtain an image of the sample using the signal information of the first and second beams; and

correct the image of the sample using the identified disturbances.