Title:
TWO PIECE MIRROR ARRANGEMENT FOR INTERFEROMETRICALLY CONTROLLED STAGE
Document Type and Number:
WIPO Patent Application WO1999002938
Kind Code:
A3
Abstract:
For interferometrically determining the X and Y coordinates of a stage, for instance for photolithography equipment, three mirrors are provided in the configuration of two independent rigid bodies. There are two extended main mirrors M1, M2 lying perpendicular to the axis of interest, and a third smaller calibration mirror M3 which is fabricated or fixed at a right angle at the end surface of one of the long mirrors. The orthogonality error between the calibration mirror M3 and the mirror to which it is attached is calibrated, the departure of parallelism with the other mirror is determined.
Inventors:
YAO SHI-KAY
Application Number:
PCT/US1998/013434
Publication Date:
April 22, 1999
Filing Date:
July 01, 1998
Export Citation:
Assignee:
ETEC SYSTEMS INC (US)
International Classes:
G01B11/00; G01B11/26; G01B9/02; G03F7/20; (IPC1-7): G01B11/26; G03F7/20
Domestic Patent References:
| WO1989005955A1 | 1989-06-29 |
Foreign References:
| US5523841A | 1996-06-04 | |||
| US5151749A | 1992-09-29 |
Download PDF:
Previous Patent: GPS GUIDED MUNITION
Next Patent: METHODS AND DEVICES FOR VERY RAPID SCAN INTERFEROMETRY
Next Patent: METHODS AND DEVICES FOR VERY RAPID SCAN INTERFEROMETRY