Apparatus for scanning a flat surface to detect defects

Details Apparatus for scanning a flat surface to detect defects Apparatus for scanning a flat surface to detect defects

1987-11-12

1989-03-14

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Optical or pre-photocell system

356431, G01N 2188

Patent

active

048126640

ABSTRACT:
A surface scanner useful for detecting defects on the surface of a water that is being processed in a vacuum equipment employs a light beam that scans the wafer surface in an arc. The scanning light beam impinges on the wafer surface at a low angle of incidence which permits the beam to pass under photosensing elements disposed in an arcuate array substantially congruous with the arc defined by the scanning light beam. The photosensing elements are patterned close to the wafer surface to receive light scattered by defects on the wafer surface.

REFERENCES:
patent: 2947212 (1960-08-01), Woods
patent: 3967114 (1976-06-01), Cornillault
patent: 4162126 (1979-07-01), Nakagawa et al.
patent: 4352564 (1982-10-01), Roach
patent: 4595289 (1986-06-01), Feldman et al.

Affiliated with

Also associated with

Rating

Apparatus for scanning a flat surface to detect defects does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for scanning a flat surface to detect defects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for scanning a flat surface to detect defects will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-895257