Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1989-06-30
1990-07-24
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
356431, G01N 2188
Patent
active
049437348
ABSTRACT:
An optical inspection system and method for detecting flaws on a diffractive surface such as a reticle or wafer, includes illuminating a surface to be inspected to generate a first scattered energy angular distribution in response to a flaw on the surface and a second scattered energy angular distribution in response to an unflawed surface; the first and second energy distributions are sensed and the minimum energy detection energy level is established; determining whether the minimum detected energy level is in a first or second predetermined energy range and indicating that no flaw is present when the minimum detected energy level is in the first range and a flaw is present when the minimum detected energy level is in the second range.
REFERENCES:
patent: 4511803 (1985-04-01), Ross
patent: 4632546 (1986-12-01), Sick
patent: 4831274 (1989-05-01), Kohno
patent: 4866288 (1989-09-01), Weber
Bou dour Abdu
Broude Sergey V.
Chase Eric T.
Johnson Carl E. A.
Ormsby Jay L.
Hsia Sherrie
Iandiorio Joseph S.
Nelms David C.
QC Optics, Inc.
LandOfFree
Inspection apparatus and method for detecting flaws on a diffrac does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Inspection apparatus and method for detecting flaws on a diffrac, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inspection apparatus and method for detecting flaws on a diffrac will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1269090