Patent · US Active

Line width error obtaining method, line width error obtaining apparatus, and inspection system

US9646374B2 · kind B2 · utility

3Cited by
2References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 24, 2016
Grant dateMay 9, 2017
Priority date
Expiry dateFeb 24, 2036

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/30148
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Optical image data is acquired by irradiating a pattern with light emitted from a light source. A threshold value is specified by internally dividing a minimum value and a maximum value of a signal amount of reference image data by a division ratio. A position corresponding to a signal amount of a threshold value is determined as an edge of a pattern of the reference image data. A position of a signal amount equal to the threshold value is determined as an edge of the pattern of the optical image data. A line width error is obtained as a difference between a first line width of the optical image data and a second line width of the reference image data. A new threshold value is specified in the case of fluctuation of a light quantity of the light source or decrease of a contrast value of the optical image data.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.