US5042945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lithographic mask structure and device for positioning the same
Assignee: Canon Inc
•
Filing: 1989-04-26
•
Granted: 1991-08-27
•
Expires: 2009-04-26
Abstract
Abstract A mask structure and a mask positioning device, executes accurate and quick positioning of a mask having a generally ring-like shape. The mask structure includes a supporting frame of a generally ring-like shape, and at least one flat surface formed by a mirror surface is provided at a peripheral part of the supporting frame. Light is projected upon the flat surface and, on the basis of detection of reflected light therefrom, the mask can be positioned with respect to the rotational direction, the inclination and orthogonal coordinate position. The mask positioning device is adapted to execute such positioning accurately and quickly.
Inventors
- 👤 Hirofumi Shibata
- 👤 Yasuaki Fukuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:26
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7003; G03F9/7007; G03F9/7011; G03F1/00; G03F1/22
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
165 words
A combination of a lithographic mask having a pattern formed on a membrane used for the manufacture of a semiconductor devices and a positioning device having a movable holder for holding and positioning the mask, the combination comprising: a generally ring-like frame member for supporting the membrane, said frame member having a substantially circumferentially extending peripheral surface portion and a substantially flat surface portion extending in a direction intersecting the membrane and providing a positional reference for the mask; a light source for projecting a light beam to said substantially flat surface portion of said frame member of the mask as held by the holder; a detector for detecting at least a portion of a light beam reflected by said flat surface portion of said frame member, said detector producing an output corresponding to the detected light beam; and control means for controlling at least one of a rotational position and a translational position of the holder in response to the output of said detector.
Claim 2
Dependent Claim
165 words
A combination of a lithographic mask having a pattern formed on a membrane used for the manufacture of a semiconductor devices and a positioning device having a movable holder for holding and positioning the mask, the combination comprising: a generally ring-like frame member for supporting the membrane, said frame member having a substantially circumferentially extending peripheral surface portion and a substantially flat surface portion extending in a direction intersecting the membrane and providing a positional reference for the mask; a light source for projecting a light beam to said substantially flat surface portion of said frame member of the mask as held by the holder; a detector for detecting at least a portion of a light beam reflected by said flat surface portion of said frame member, said detector producing an output corresponding to the detected light beam; and control means for controlling at least one of a rotational position and a translational position of the holder in response to the output of said detector.
Claim 3
Dependent Claim
36 words
A device according to claim 1, wherein said detector includes a flat light receiving surface and wherein said detector produces a signal corresponding to the position of incidence of the light upon said light receiving surface.
References Cited (Backward Citations)
US3449961A
Cited
US3583815A
Cited
US3657792A
Cited
US3695767A
Cited
US3954339A
Cited
US4573791A
Cited
DE3025488A1
Cited
US4298281A
Cited
US4801208A
Cited
US4801120A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-08-26 | 1995-02-25 | 1995-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-26 | 1999-02-25 | 1999-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-26 | 2003-02-25 | 2003-08-27 | $7700.00 | Window Closed / Lapsed |