US3449221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making a monometallic mask
Assignee: Dynamics Research Corp
•
Filing: 1966-12-08
•
Granted: 1969-06-10
•
Expires: 1986-12-08
Abstract
No abstract record available.
Inventors
- 👤 Lowell E Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:50
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/20; B; B41; B41C; B41C1/00; B41C1/14; C; C23; C23F; C23F1/00; C23F1/02; C23F1/04; G03F7/00; G03F7/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
A PROCESS FOR MANUFACTURING A MONOMETALLIC MASK PROVIDING AN EFFECTIVE PATTERN OF SURFACE AREA AND APERTURE AREA COMPRISING THE STEPS OF (1) FORMING A LAMINATED STRUCTURE COMPRISING A TOP LAYER OF PHOTORESIST MATERIAL CARRIED ON A LAYER OF A FIRST METAL, SAID FIRST METAL LAYER BEING SUPPORTED BY A STRUCTURE OF A SECOND METAL, THE PERIPHERY OF SAID FIRST METAL LAYER BEING GREATER THAN THE PERIPHERY OF SAID TOP PHOTORESIST LAYER AND SMALLER THAN THE PERIPHERY OF SAID SECOND METAL STRUCTURE; AND (2) DEPOSITING AN APERTURE-DEFINING LAYER OF ADDITIONAL SECOND METAL ON THE EXPOSED FACES OF SAID FIRST AND SECOND METAL TO A THICKNESS REACHING AT LEAST TO THE TOP FACE OF SAID TOP PHOTORESIST LAYER, AND REMOVING SAID FIRST METAL, SAID PHOTORESIST MATERIAL AND ANY OF SAID SECOND METAL ALIGNED WITH AND UNDER THE FACES OF SAID PHOTORESIST MATERIAL.
Claim 2
Dependent Claim
140 words
A PROCESS FOR MANUFACTURING A MONOMETALLIC MASK PROVIDING AN EFFECTIVE PATTERN OF SURFACE AREA AND APERTURE AREA COMPRISING THE STEPS OF (1) FORMING A LAMINATED STRUCTURE COMPRISING A TOP LAYER OF PHOTORESIST MATERIAL CARRIED ON A LAYER OF A FIRST METAL, SAID FIRST METAL LAYER BEING SUPPORTED BY A STRUCTURE OF A SECOND METAL, THE PERIPHERY OF SAID FIRST METAL LAYER BEING GREATER THAN THE PERIPHERY OF SAID TOP PHOTORESIST LAYER AND SMALLER THAN THE PERIPHERY OF SAID SECOND METAL STRUCTURE; AND (2) DEPOSITING AN APERTURE-DEFINING LAYER OF ADDITIONAL SECOND METAL ON THE EXPOSED FACES OF SAID FIRST AND SECOND METAL TO A THICKNESS REACHING AT LEAST TO THE TOP FACE OF SAID TOP PHOTORESIST LAYER, AND REMOVING SAID FIRST METAL, SAID PHOTORESIST MATERIAL AND ANY OF SAID SECOND METAL ALIGNED WITH AND UNDER THE FACES OF SAID PHOTORESIST MATERIAL.
References Cited (Backward Citations)
US1376365A
Cited
US2226383A
Cited
US2469689A
Cited
US3179543A
Cited
US3192136A
Cited
US3359192A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-06-09 | 1972-12-09 | 1973-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-09 | 1976-12-09 | 1977-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-09 | 1980-12-09 | 1981-06-10 | $7700.00 | Window Closed / Lapsed |