US4704020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projection optical apparatus
Assignee: Nikon Corp
•
Filing: 1986-09-04
•
Granted: 1987-11-03
•
Expires: 2006-09-04
Abstract
Abstract A projection optical apparatus for projecting the pattern of a mask onto a substrate through a projection optical system includes a stage for supporting thereon a substrate having a plurality of marks for detection on the surface thereof, first detecting means for detecting the amount of inclination of the surface of the substrate relative to the surface on which the pattern is projected and imaged, through the projection optical system, second detecting means for detecting the amount of inclination of the surface of the substrate relative to a predetermined reference plane independently of the projection optical system, and calibrating means for calibrating the amount of inclination detected by the second detecting means on the basis of the amount of inclination detected by the first detecting means.
Inventors
- 👤 Masaichi Murakami
- 👤 Hidemi Kawai
- 👤 Kyoichi Suwa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:26
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7003; G03F9/7023
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
126 words
A projection optical apparatus for projecting the pattern of a mask onto a substrate through a projection optical system, including: a stage for supporting thereon a substrate having a plurality of marks for detection on the surface thereof; first detecting means for detecting the amount of inclination of the surface of said substrate relative to the surface on which said pattern is projected and imaged, through said projection optical system; second detecting means for detecting the amount of inclination of the surface of said substrate relative to a predetermined reference plane independently of said projection optical system; and calibrating means for calibrating the amount of inclination detected by said second detecting means on the basis of the amount of inclination detected by said first detecting means.
Claim 2
Dependent Claim
126 words
A projection optical apparatus for projecting the pattern of a mask onto a substrate through a projection optical system, including: a stage for supporting thereon a substrate having a plurality of marks for detection on the surface thereof; first detecting means for detecting the amount of inclination of the surface of said substrate relative to the surface on which said pattern is projected and imaged, through said projection optical system; second detecting means for detecting the amount of inclination of the surface of said substrate relative to a predetermined reference plane independently of said projection optical system; and calibrating means for calibrating the amount of inclination detected by said second detecting means on the basis of the amount of inclination detected by said first detecting means.
Claim 3
Dependent Claim
53 words
A projection optical apparatus according to claim 1, wherein said first detecting means includes a TTL detecting optical system having a light-receiving device capable of detecting the surface on which said pattern is projected and imaged, through said mask and said projection optical system, and detecting said marks for detection on said substrate.
Claim 4
Dependent Claim
65 words
A projection optical apparatus according to claim 1, wherein said second detecting means includes a projection device for projecting a light beam onto said substrate, and a light-receiving device having a converging optical system for converging the reflected light beam reflected from the surface of said substrate to thereby form a light spot, and a light-receiving element for detecting the position of said light spot.
Claim 5
Dependent Claim
35 words
A projection optical apparatus according to claim 3, wherein said calibrating means includes a pair of rotatable plain parallel plates provided on the light-receiving optical path of said light-receiving device to displace said light spot.
Claim 6
Dependent Claim
52 words
A projection optical apparatus according to claim 1, wherein said second detecting means is at least three air micro type position detecting devices provided around said projection optical system, and the back pressure of the air of each of said air micro type position detecting devices is calibrated by said calibrating means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-02 | 1991-05-04 | 1991-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-02 | 1995-05-04 | 1995-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-02 | 1999-05-04 | 1999-11-03 | $7700.00 | Window Closed / Lapsed |