Patent · US Expired

System and method for inspection of a substrate that has a refractive index

US7030978B2 · kind B2 · utility

10Cited by
4References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 25, 2003
Grant dateApr 18, 2006
Priority date
Expiry dateFeb 16, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/8806
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A system and method for inspection of a substrate having a first refractive index, the method including the steps of: (i) defining an apodization scheme in response to a characteristic of the layer; (ii) applying an apodizer to apodize a beam of radiation in response to the apodization scheme; (iii) directing the apodized beam of radiation to impinge on the substrate, whereby a plurality of rays are reflected from the substrate; whereas the apodized beam of radiation propagates through an at least partially transparent medium having a third refractive index and an at least partially transparent layer having a second refractive index and is subsequently reflected from the substrate; whereas the second refractive index differs from the first refractive index and from the third refractive index; and (iv) detecting at least some of the plurality of reflected rays.

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