Beam spot position detector having a detector moving mechanism

Radiant energy – Photocells; circuits and apparatus – With circuit for evaluating a web – strand – strip – or sheet

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2505594, 356376, G01N 2186

Patent

active

055324991

ABSTRACT:
A method for measuring surface topography characterized by making multiple scans of the surface with a laser scanning unit and utilizing the multiple scans to create representations of the surface's topography. The surface topography data can also be used to calculate the compressive or tensile stress caused by a thin film applied to the surface of a semiconductor wafer. The apparatus of the present invention scans a laser beam across a surface in an x direction, and detects displacements of a reflected portion of the laser beam in a z direction. A pair of photodetectors are used to translate z direction displacements of the reflected beam into analog signals which are digitized and input into a microcomputer for analysis. The multiple scans of the surface are preferably accomplished by placing the workpiece on a pedestal which can be rotated to various angular positions.

REFERENCES:
patent: 3406292 (1968-10-01), Geier et al.
patent: 3679307 (1972-07-01), Zoot et al.
patent: 4145140 (1979-03-01), Fujii
patent: 4297034 (1981-10-01), Ito et al.
patent: 4386272 (1983-05-01), Check, Jr. et al.
patent: 4506149 (1985-03-01), Utsumi
patent: 4667113 (1987-05-01), Nakajima et al.
patent: 4672196 (1987-06-01), Canino
patent: 4788421 (1988-11-01), Ogawa et al.
patent: 4815857 (1989-03-01), Bragd
patent: 4900940 (1990-02-01), Nakamura
patent: 5134303 (1992-07-01), Blech et al.
patent: 5162642 (1992-11-01), Akamatsu et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Beam spot position detector having a detector moving mechanism does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Beam spot position detector having a detector moving mechanism, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Beam spot position detector having a detector moving mechanism will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1508464

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.