Method of positioning a wafer with respect to a focal plane of a

Details Method of positioning a wafer with respect to a focal plane of a Method of positioning a wafer with respect to a focal plane of a

1991-04-04

1993-12-07

Rosenberger, Richard A.

Optics: measuring and testing

By alignment in lateral direction

With light detector

2502014, G01B 1100

Patent

active

052687449

ABSTRACT:
A method of positioning a surface of a wafer with respect to a focal plane of an optical system is disclosed. The method includes: forming an image of a pattern in a first region of a wafer through the optical system; projecting through the optical system a radiation beam to the first region of the wafer and projecting through the optical system a reflection beam from the first region of the wafer onto a predetermined plane; evaluating the formed image to determine the focal plane of the optical system and determining, as a reference position, a position of incidence on the predetermined plane of the reflection beam from the first region of the wafer at a level corresponding to the determined focal plane; projecting a radiation beam to a second region of the wafer and projecting through the optical system a reflection beam from the second region of the wafer onto the predetermined plane; and positioning the second region of the wafer on the determined focal plane of the optical system on the basis of a position of incidence of the reflection beam from the second region of the wafer with respect to the determined reference position.

REFERENCES:
patent: 4650983 (1987-03-01), Suwa
patent: 4705940 (1987-11-01), Kohno
patent: 4952815 (1990-08-01), Nishi

Affiliated with

Also associated with

Rating

Method of positioning a wafer with respect to a focal plane of a 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 of positioning a wafer with respect to a focal plane of a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of positioning a wafer with respect to a focal plane of a will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2019230