Optics: measuring and testing – Angle measuring or angular axial alignment – Sides of angle or axes being aligned transverse to optical...
Patent
1993-06-17
1995-09-19
Limanek, Robert P.
Optics: measuring and testing
Angle measuring or angular axial alignment
Sides of angle or axes being aligned transverse to optical...
356400, 250548, 25055929, G01N 2186, G01B 1100
Patent
active
054520789
ABSTRACT:
A method and apparatus for finding wafer index marks and centers. A wafer having a flat or notch along its edge is placed on a rotatable platform so that a portion of the wafer's edge is positioned within a sensor assembly. The wafer is rotated, and the sensor reads the distance from the center of rotation to the edge of the wafer. This distance is measured at several angles of the wafer and the data is stored in a digital computer as a series of datapoints including an angle and a distance. A computer-implemented process calculates various geometries concerning the wafer including the location of the index mark and the center of the wafer.
REFERENCES:
patent: 4457664 (1984-07-01), Jodell et al.
patent: 4819167 (1989-04-01), Cheng et al.
patent: 4853880 (1989-08-01), Akamatsu et al.
patent: 4907035 (1990-03-01), Galburt et al.
patent: 5125791 (1992-06-01), Volovich
patent: 5159202 (1992-10-01), Ametani
patent: 5194743 (1993-03-01), Aoyama et al.
patent: 5238354 (1993-08-01), Volovich
patent: 5264918 (1993-11-01), Kagami
Hardy David B.
Koo Ann f.
Limanek Robert P.
LandOfFree
Method and apparatus for finding wafer index marks and centers 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 finding wafer index marks and centers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for finding wafer index marks and centers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1832507