Patent · US Active

Apparatus and method of measuring a property of a substrate

US8786825B2 · kind B2 · utility

24Cited by
3References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 20, 2009
Grant dateJul 22, 2014
Priority date
Expiry dateAug 24, 2030

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F9/7088
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The present invention makes the use of measurement of a diffraction spectrum in or near an image plane in order to determine a property of an exposed substrate. In particular, the positive and negative first diffraction orders are separated or diverged, detected and their intensity measured to determine overlay (or other properties) of exposed layers on the substrate.

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