Patent · US Expired

Automatic calibration of a masking process simulator

US6768958B2 · kind B2 · utility

17Cited by
6References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 26, 2002
Grant dateJul 27, 2004
Priority date
Expiry dateNov 26, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70616
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method and system for automatically calibrating a masking process simulator using a calibration mask and process parameters to produce a calibration pattern on a wafer. A digital image is created of the calibration pattern, and the edges of the pattern are detected. Data defining the calibration mask and the process parameters are input to a process simulator to produce an alim image estimating the calibration pattern that would be produced by the masking process. The alim image and the detected edges of the digital image are then overlaid, and a distance between contours of the pattern in the alim image and the detected edges is measured. One or more mathematical algorithms are used to iteratively change the values of the processing parameters until a set of processing parameter values are found that produces a minimum distance between the contours of the pattern in the alim image and the detected edges.

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