Patent US4374698A successfully refreshed from Google Patents.
US4374698A
Expired / Lapsed
US
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Method of manufacturing a semiconductor device
Assignee: US Philips Corp
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Filing: 1981-07-09
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Granted: 1983-02-22
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Expires: 2001-07-09
Abstract
Abstract A method of manufacturing a semiconductor device in which layers of silicon nitride and silicon oxide are etched by bringing the layers into contact with constituents of a plasma which is formed in a gas mixture which contains a fluoride compound and an oxygen compound. By addition of from 1 to 15% by volume of a gaseous compound which contains a halogen other than fluoride to the gas mixture, silicon nitride layers can be etched away at least five times faster than silicon oxide layers. The method is thus suitable in practice, for example, for manufacturing a silicon nitride mask for the formation of a field oxide in LOCOS processes.
Inventors
- 👤 Jozef A. M. Sanders
- 👤 Franciscus H. M. Sanders
- 👤 Hendrikus Kalter
- 👤 Everhardus P. G. T. van de Ven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:02
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
71 words
A method of manufacturing a semiconductor device comprising etching a layer of silicon nitride which is present on a substrate by bringing the layer into contact with constituents of a plasma formed in a gas mixture which contains a fluoride compound and an oxygen compound, characterized in that from 1 to 15% by volume of a gaseous compound which contains a halogen other than fluoride is added to the gas mixture.
Claim 2
Independent Claim
71 words
A method of manufacturing a semiconductor device comprising etching a layer of silicon nitride which is present on a substrate by bringing the layer into contact with constituents of a plasma formed in a gas mixture which contains a fluoride compound and an oxygen compound, characterized in that from 1 to 15% by volume of a gaseous compound which contains a halogen other than fluoride is added to the gas mixture.
Claim 3
Dependent Claim
40 words
A method as claimed in claim 1, characterized in that the gas mixture in which the plasma is formed contains CF 4 as the fluoride compound and CF 2 Cl 2 as the compound containing a halogen other than fluoride.
Claim 4
Dependent Claim
34 words
A method as claimed in claim 1 or 2, characterized in that the gas mixture in which the plasma is formed contains from 1 to 4% by volume of CF 2 Cl 2 .
Claim 5
Dependent Claim
39 words
A method as claimed in claim 1, characterized in that the gas mixture in which the plasma is formed contains CF 4 as the fluoride compound and CF 3 Br as the compound containing a halogen other than fluoride.
Claim 6
Dependent Claim
33 words
A method as claimed in claim 1 or 4, characterized in that the gas mixture in which the etching plasma is formed contains from 2 to 8% by volume of CF 3 Br.
Claim 7
Independent Claim
38 words
A method as claimed in one of claims 1, 2 or 4 characterized in that the gas mixture in which the plasma is formed contains from 3 to 10% by volume of O 2 as the oxygen compound.
Claim 8
Independent Claim
37 words
A method as claimed in one of claims 1, 2 or 4, characterized in that the gas mixture in which the plasma is formed contains from 20 to 40% by volume of NO as the oxygen compound.
Claim 9
Dependent Claim
33 words
A method as claimed in claim 3, characterized in that the gas mixture in which the plasma is formed contains from 3 to 10% by volume of O 2 as the oxygen compound.
Claim 10
Dependent Claim
33 words
A method as claimed in claim 5, characterized in that the gas mixture in which the plasma is formed contains from 3 to 10% by volume of O 2 as the oxygen compound.
Claim 11
Dependent Claim
32 words
A method as claimed in claim 3, characterized in that the gas mixture in which the plasma is formed contains from 20 to 40% by volume of NO as the oxygen compound.
Claim 12
Dependent Claim
32 words
A method as claimed in claim 5, characterized in that the gas mixture in which the plasma is formed contains from 20 to 40% by volume of NO as the oxygen compound.
References Cited (Backward Citations)
US4174251A
Cited
US4226665A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |