Surface inspection apparatus

Details Surface inspection apparatus Surface inspection apparatus

1998-11-02

2000-08-15

Font, Frank G.

Optics: measuring and testing

Inspection of flaws or impurities

Surface condition

3562374, 3562372, G01N 2100

Patent

active

061044814

ABSTRACT:
A wafer surface inspection apparatus comprises a light source, an optical system for focusing the light beams from the light source onto the wafer surface, a scanning means for scanning the focused point over a predetermined range on the wafer surface, a photo detector including an photoelectric converter for sensing scattered light from the focused point, and a signal detector for detecting signals from the photo detector, in which the light source is a light source for emitting two different wavelengths, the optical system is adapted to focus the light beams of the two wavelengths on one and the same point on the wafer surface, and the photo detector is adapted to sense the two wavelengths separately, and further comprises a discriminating portion for discriminating between a foreign matter or a scratch on the wafer surface and a recess in a spot form existing on the wafer surface by utilizing outputs from the signal detector.

REFERENCES:
patent: 4966457 (1990-10-01), Hayano et al.
patent: 5179422 (1993-01-01), Peterson
patent: 5410400 (1995-04-01), Shishido et al.
patent: 5486919 (1996-01-01), Tsuji et al.

Affiliated with

Also associated with

Rating

Surface inspection apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Surface inspection apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Surface inspection apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2012926