Patent · US Expired

Particulate inspection of fluids using interferometric light measurements

US5061070A · kind A · utility

21Cited by
7References
42Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 22, 1988
Grant dateOct 29, 1991
Priority date
Expiry dateApr 22, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2015/0238
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for monitoring process fluids used in the manufacture of semiconductor components and other microelectronic devices relies upon detection of the phase shift of a pair of optical energy beams encountering a bubble or particle in the fluid. The system distinguishes between bubbles and particles having indices of refraction greater than the surrounding fluid and between different types and sizes of particles.

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