Reference image generation method and pattern inspection method

Patent metadata

Field	Value
Publication number	US-2020294218-A1
Application number	US-202016817932-A
Country	US
Kind code	A1
Filing date	Mar 13, 2020
Priority date	Mar 13, 2019
Publication date	Sep 17, 2020
Grant date	—

Abstract

To include reading design data of a plurality of patterns formed on a sample and characteristic information indicating characteristics of each of the patterns from a storage device, the characteristic information being additionally written in the design data, dividing a pattern formed region of the sample on which the patterns are formed, into a plurality of regions where the characteristics are different from each other on a basis of the characteristic information, calculating parameter information according to the characteristics with respect to each of the regions, where the parameter information is provided for generating a reference image from the design data to be used in an inspection of the patterns, and generating the reference image from the design data on a basis of the calculated parameter information.

First claim

1 . A reference image generation method comprising:
reading design data of a plurality of patterns formed on a sample and characteristic information indicating characteristics of each of the patterns from a storage device, the characteristic information being additionally written in the design data; dividing a pattern formed region of the sample on which the patterns are formed, into a plurality of regions where the characteristics are different from each other on a basis of the characteristic information; calculating parameter information according to the characteristics with respect to each of the regions, where the parameter information is provided for generating a reference image from the design data to be used in an inspection of the patterns; and generating the reference image from the design data on a basis of the calculated parameter information.

2 . The method of claim 1 , wherein the characteristic information is pattern type information indicating types of the patterns.

3 . The method of claim 1 , wherein the characteristic information is at least either inspection rank information indicating inspection ranks of the patterns or contour information indicating contours of the patterns.

4 . The method of claim 2 , further comprising:
before the dividing of the pattern formed region into the regions, calculating a density and number of edges of each of the patterns of the design data with respect to each unit of the design data having a same image size as a generation unit of the reference image; generating the pattern type information by determining a type of each of the patterns with respect to each unit of the design data on a basis of the calculated density and the calculated number of edges; and adding the pattern type information to the design data with respect to each unit of the design data.

5 . The method of claim 3 , comprising
before the dividing of the pattern formed region into the regions, adding at least either the inspection rank information or the contour information to the design data in response to a user operation.

6 . The method of claim 4 , wherein the generating of the pattern type information comprises determining a type of each of the patterns by performing labeling to classify a plurality of patterns where densities and numbers of edges are close to each other into a same group on a basis of the calculated density and the calculated number of edges.

7 . A pattern inspection method comprising:
reading design data of a plurality of patterns formed on a sample and characteristic information indicating characteristics of each of the patterns from a storage device, the characteristic information being additionally written in the design data; dividing a pattern formed region of the sample on which the patterns are formed, into a plurality of regions where the characteristics are different from each other on a basis of the characteristic information; calculating parameter information according to the characteristics with respect to each of the regions, where the parameter information is provided for generating a reference image from the design data to be used in an inspection of the patterns; generating the reference image from the design data on a basis of the calculated parameter information; and inspecting a defect of the patterns on a basis of the reference image and an optical image obtained by imaging the sample.

Assignees

• Nuflare Technology Inc

Inventors

• Yasui Yoshitaka
• Isomura Lkunao

Classifications

• G06T2207/30148

  Semiconductor; IC; Wafer · CPC title

• G06T2207/10061

  from scanning electron microscope · CPC title

• G06T7/001 Primary

  using an image reference approach · CPC title

• G06T7/12

  Edge-based segmentation · CPC title

• G06T7/13

  Edge detection · CPC title