Method and apparatus for mapping the edge and other characterist

Details Method and apparatus for mapping the edge and other characterist Method and apparatus for mapping the edge and other characterist

1994-10-07

1996-08-13

Evans, F. L.

Optics: measuring and testing

For optical fiber or waveguide inspection

356371, 356375, 356376, 25055922, 25055936, 25055929, G01B 1124

Patent

active

055461794

ABSTRACT:
A method and apparatus for mapping the edge and other characteristics of a wafer. A method for mapping the edge of a wafer includes steps of providing a sensor device over a surface of a wafer on a testing chuck. A beam of electromagnetic energy emitted by the sensor device is reflected from the surface of the wafer and its intensity is measured by the sensor device. The sensor device is focussed and is then positioned at the edge of the wafer by measuring the intensity of the reflected beam as the sensor device is moved. A changed intensity signifies that the sensor device is located at the edge of the wafer. The wafer is incrementally rotated and the intensity of the reflected beam is measured at multiple locations on the edge of the wafer to provide datapoints used in the edge mapping. The height of the wafer is mapped by moving the sensor device in a z direction perpendicular to the surface of the wafer. A focal distance is found where the reflected beam is at a maximum intensity. Multiple focal distances taken from different locations on the wafer are compared to map the height of the wafer. The reflectivity of the wafer is also detected at the focal distance.

REFERENCES:
patent: 3406292 (1968-10-01), Geier et al.
patent: 4145140 (1979-03-01), Fujii
patent: 4297034 (1981-10-01), Ito et al.
patent: 4402613 (1983-09-01), Daly et al.
patent: 4457664 (1984-07-01), Judell et al.
patent: 4667113 (1987-05-01), Nakajima et al.
patent: 4672196 (1987-06-01), Canino
patent: 4815857 (1989-03-01), Bragd
patent: 4819167 (1989-04-01), Cheng et al.
patent: 4853880 (1989-08-01), Akamatsu et al.
patent: 4900940 (1990-02-01), Nakamura
patent: 4907035 (1990-03-01), Galburt et al.
patent: 5125791 (1992-06-01), Volovich
patent: 5134303 (1992-07-01), Biech et al.
patent: 5159202 (1992-10-01), Ametani
patent: 5162642 (1992-11-01), Akamatsu et al.
patent: 5194743 (1993-03-01), Aoyama et al.
patent: 5238354 (1993-08-01), Volovich
patent: 5264918 (1993-11-01), Kagami
patent: 5270560 (1993-12-01), Cheng
patent: 5369286 (1994-11-01), Cheng

Affiliated with

Also associated with

Rating

Method and apparatus for mapping the edge and other characterist does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for mapping the edge and other characterist, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for mapping the edge and other characterist will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1052821