Patent US5629524A successfully refreshed from Google Patents.
Patent US4407850A successfully refreshed from Google Patents.
US4407850A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Profile control photoresist
Assignee: Lam Research Corp
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Filing: 1982-01-11
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Granted: 1983-10-04
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Expires: 2002-01-11
Abstract
Abstract Anisotropic etching of thick photoresist under plasma conditions to achieve a vertical side wall with or without undercutting is accomplished by operating at a low excitation frequency, a pressure in the range of 0.3 to 2 Torr and a controlled concentration of active species.
Inventors
- 👤 Richard H. Bruce
- 👤 Alan R. Reinberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:51
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287; G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/094; G03F7/26; G03F7/36
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
131 words
A method of patterning a photoresist such as to obtain a vertical wall comprising: (a) depositing the photoresist in a thick layer on the order of one micron thick on a substrate; (b) depositing a thin layer of silicon dioxide over said thick resist; (c) depositing a thin layer of resist on said layer of silicon dioxide; (d) patterning said thin resist; (e) patterning said layer of silicon dioxide; (f) patterning said thick photoresist with steps comprising: (1) disposing said substrate between the plates of parallel plate reactor operating in the frequency range between 50 and 5000 KHz; (2) supplying a reactant gas containing to said reactor for generation of a plasma containing chemically active species; (3) establishing a pressure in said reactor in the range of 0.1 to 2 Torr.
Claim 2
Independent Claim
131 words
A method of patterning a photoresist such as to obtain a vertical wall comprising: (a) depositing the photoresist in a thick layer on the order of one micron thick on a substrate; (b) depositing a thin layer of silicon dioxide over said thick resist; (c) depositing a thin layer of resist on said layer of silicon dioxide; (d) patterning said thin resist; (e) patterning said layer of silicon dioxide; (f) patterning said thick photoresist with steps comprising: (1) disposing said substrate between the plates of parallel plate reactor operating in the frequency range between 50 and 5000 KHz; (2) supplying a reactant gas containing to said reactor for generation of a plasma containing chemically active species; (3) establishing a pressure in said reactor in the range of 0.1 to 2 Torr.
Claim 3
Dependent Claim
34 words
The method according to claim 1 for obtaining a vertical profile without any undercutting comprising adjusting the concentration of said active species to approximately 20 percent and maintaining said pressure at about 0.3 Torr.
Claim 4
Dependent Claim
38 words
The method according to claim 1 comprising operating said reactor at least one of a pressure above approximately 0.3 Torr and a concentration of active species above approximately 20 percent to obtain a vertical side wall with undercut.
Claim 5
Dependent Claim
12 words
The method according to claim 1 wherein said active species comprises oxygen.
Claim 6
Dependent Claim
40 words
The method according to claim 4 comprising operating with the concentration of oxygen between approximately 20 percent and 100 percent, the remainder of the gas being an inert gas and at a pressure between approximately 0.3 Torr and 2 Torr.
Claim 7
Dependent Claim
17 words
The method according to claim 1 or 5 comprising operating at a frequency of about 100 KHz.
Claim 8
Dependent Claim
33 words
The method according to claim 1 or 5 wherein said thick photoresist is approximately one micron thick, said protective layer approximately 1,000 A thick and said thin photoresist layer approximately 0.5 microns thick.
Claim 9
Dependent Claim
23 words
The method according to claim 1 or 5 wherein said process is carried out operating said reactor at approximately 0.62 w/cm 2 .
Claim 10
Dependent Claim
22 words
The method according to claim 1 wherein said step of depositing a protective layer comprises plasma depositing low temperature SiO 2 .
Claim 11
Dependent Claim
20 words
The method according to claim 1 wherein the spacing of the parallel plates in said reactor is approximately 6 mm.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |