US 11,573,188 B2 · Image processing method and device for CDSEM

Abstract

The present invention provides an image processing method for CDSEM for determining a measuring range of an image of a target pattern measured by a CDSEM machine. The image processing method of CDSEM comprises: obtaining a first gray scale image based on the image of the target pattern; performing Fourier transform to the first gray scale image to obtain a first frequency spectrum distribution; filtering out frequency spectrum components whose absolute values of ordinate are greater than preset threshold in the first frequency spectrum distribution to obtain a second frequency spectrum distribution, the preset threshold relates to the background noise and the signal frequency of SRAF features; and determining the measuring range based on the second frequency spectrum distribution.

Claims20

Dependent claims

An image processing method for a CDSEM, comprising:

providing a sample having a pattern to be measured;
acquiring a first gray scale image of the pattern on the CDSEM;
performing Fourier transform to the first gray scale image to obtain a first frequency spectrum distribution comprising first frequency spectrum components;
filtering the first frequency spectrum distribution and excluding those having absolute values of ordinate greater than a preset threshold from the first frequency spectrum components, to obtain a second frequency spectrum distribution comprising second frequency spectrum components;
and
determining a measuring range of the pattern on the CDSEM based on the second frequency spectrum distribution.

3 more elements

An image processing device for a CDSEM machine, comprising:

a memory cell;
and
a processor coupled to the memory cell, wherein the processor is configured to:
obtain a first gray scale image based on an image of a target pattern to be measured;
perform Fourier transform to the first gray scale image to obtain a first frequency spectrum distribution comprising first frequency spectrum components;
filter the first frequency spectrum distribution and exclude those having absolute values of ordinate greater than a preset threshold from the first frequency spectrum components, to obtain a second frequency spectrum distribution comprising second frequency spectrum components;
and
determining a measuring range of the pattern on the CDSEM based on the second frequency spectrum distribution.

5 more elements

Dependencies are inferred from the claim text.

Image processing method and device for CDSEM

Life of this patent

Image processing method and device for CDSEM

Life of this patent

Abstract

Claims20