Patent · US Expired

Determination of center of focus by diffraction signature analysis

US6606152B2 · kind B2 · utility

80Cited by
20References
50Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 23, 2002
Grant dateAug 12, 2003
Priority date
Expiry dateJul 23, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70641
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

Methods for determination of parameters in lithographic devices and applications by diffraction signature difference analysis, including determination of center of focus in lithography devices and applications. Latent image analysis may be employed with exposed but undeveloped lithographic substrates. Control methods are provided for process control of center of focus in lithography devices utilizing diffraction signature difference analysis.

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