US4844773A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for etching silicon nitride film
Assignee: Texas Instruments Inc
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Filing: 1988-04-26
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Granted: 1989-07-04
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Expires: 2008-04-26
Abstract
Abstract A process for etch of polysilicon films which utilizes the combination of remote and in situ plasma in a low pressure process module and the plasma is generated form a mixture of a source of Fluorine and Helium with the process chamber within the process module being generally at ambient temperatures.
Inventors
- 👤 Lee M. Loewenstein
- 👤 Cecil J. Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:53
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
72 words
A process for etch of a Silicon Nitride film comprising the steps of: (a) disposing sail film in a low pressure process chamber; (b) generating remote plasma from a gas comprised of a mixture of a Fluorine source and Helium; (c) introducing said remote plasma into said chamber and to said film; and (d) generating an in situ plasma within said chamber from a gas mixture of a Fluorine source and Helium.
Claim 2
Dependent Claim
72 words
A process for etch of a Silicon Nitride film comprising the steps of: (a) disposing sail film in a low pressure process chamber; (b) generating remote plasma from a gas comprised of a mixture of a Fluorine source and Helium; (c) introducing said remote plasma into said chamber and to said film; and (d) generating an in situ plasma within said chamber from a gas mixture of a Fluorine source and Helium.
Claim 3
Dependent Claim
18 words
The process as set forth in claim 1 wherein said remote and in situ plasmas are generated simultaneously.
Claim 4
Dependent Claim
38 words
The process as set forth in claim 1 wherein the Fluorine source is taken from the group of CF 4 , F 2 , SF 6 , NF 3 , and CHF 3 , singly or in combination.
Claim 5
Dependent Claim
17 words
The process as set forth in claim 1 wherein the process is carried out at ambient temperature.
Claim 6
Dependent Claim
15 words
The process as set forth in claim 1 wherein the low pressure is 0.7 Torr.
Claim 7
Dependent Claim
32 words
The precess as set forth in claim 1 wherein mixture for the in situ and remote plasmas has a flow comprised of Helium at 1000 sccm and CF 4 at 200 sccm.
Claim 8
Dependent Claim
34 words
The process as set forth in claim 1 wherein the power utilized for generating the remote plasma is 400 watts at 2450 MHz and the in situ plasma is 225 watts at 13.56 MHz.
Claim 9
Dependent Claim
56 words
A process for etch of a Silicon Nitride film comprising the steps of: (a) disposing said film in a first chamber; (b) generating at least free radicals from a fluorine containing gas in a second chamber remote from the first chamber; (c) introducing said at least free radicals into said first chamber and to said film.
Claim 10
Dependent Claim
56 words
A process for etch of a Silicon Nitride film comprising the steps of: (a) disposing said film in a first chamber; (b) generating at least free radicals from a fluorine containing gas in a second chamber remote from the first chamber; (c) introducing said at least free radicals into said first chamber and to said film.
Claim 11
Dependent Claim
38 words
The process as set forth in claim 8 wherein the fluorine containing gas taken from the group of CF 4 , F 2 , SF 6 , NF 3 , and CHF 3 , singly or in combination.
Claim 12
Dependent Claim
17 words
The process as set forth in claim 8 wherein the process is carried out at ambient temperature.
Claim 13
Dependent Claim
26 words
The process as set forth in claim 8 wherein helium is added to the fluorine source prior to the generating of said at least free radicals.
Claim 14
Dependent Claim
18 words
The process as set forth in claim 8 wherein the process ic carried out at approximately 0.7 Torr.
Claim 15
Dependent Claim
25 words
The process as set forth in claim 8 wherein the power utilized for generating said at least free radicals is 400 watts at 2450 MHz.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-03 | 1993-01-02 | 1993-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-03 | 1997-01-02 | 1997-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-03 | 2001-01-02 | 2001-07-04 | $7700.00 | Window Closed / Lapsed |