Patent · US Expired

Film thickness measurement apparatus with tilting stage and method of operation

US5729343A · kind A · utility

15Cited by
10References
29Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 22, 1996
Grant dateMar 17, 1998
Priority date
Expiry dateOct 22, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B11/0675
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A film measurement apparatus having a stage with a support surface on which a substrate coated with a film may rest. An extended light source faces the stage, and an imager is aimed at the stage to capture the reflection of the light source. The imager includes a receiver upon which an image of at least an extended portion of the substrate may be generated, and a processor in communication with the imager is operable to calculate the thickness of the film at plurality of locations. The stage may be tilted to empirically measure an average illumination and the contrast between interference fringes, avoiding theoretical estimates provided by Fresnel'equation.

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