US5719086A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for isolating elements of semiconductor device
Assignee: SK Hynix Inc
•
Filing: 1996-11-01
•
Granted: 1998-02-17
•
Expires: 2016-11-01
Abstract
Abstract A method for isolating the elements of semiconductor devices, in which bird's beak can be restrained by accumulating nitrogen atoms between a pad oxide film and a silicon substrate and the etch depth of a silicon substrate can be controlled by use of wet etch to remove the oxide which is grown on the silicon substrate at a low temperature after formation of nitride spacer, thereby reproducing good profiles of the field oxide film.
Inventors
- 👤 Young Bog Kim
- 👤 Sung Ku Kwon
- 👤 Byung Jin Cho
- 👤 Jong Choul Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:01
CPC Classifications
H; H10; H10W; H10W10/00; H10P; H10P14/00; H10P14/60; H10P14/61; H10W10/01; H10W10/011; H10W10/012; H10W10/0128; H10W10/10; H10W10/13
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
131 words
A method for isolating the elements of semiconductor devices, comprising the steps of: forming a stress buffer layer on a semiconductor substrate; annealing in a gas atmosphere containing nitrogen to form a nitrogen-accumulated layer at the interface between the semiconductor substrate and the buffer layer; depositing an oxidation-preventing layer entirely over the resulting structure; selectively etching the oxidation-preventing layer and the buffer layer at a field region to give a first recessed region; forming a spacer for restraining a bird's beak at the side wall of the first recessed region; forming a sacrificial oxide film in a first oxidation process; removing the sacrificial oxide film in a wet etching process to form a second recessed region in the semiconductor substrate; and forming a field oxide film in a second oxidation process.
Claim 2
Independent Claim
131 words
A method for isolating the elements of semiconductor devices, comprising the steps of: forming a stress buffer layer on a semiconductor substrate; annealing in a gas atmosphere containing nitrogen to form a nitrogen-accumulated layer at the interface between the semiconductor substrate and the buffer layer; depositing an oxidation-preventing layer entirely over the resulting structure; selectively etching the oxidation-preventing layer and the buffer layer at a field region to give a first recessed region; forming a spacer for restraining a bird's beak at the side wall of the first recessed region; forming a sacrificial oxide film in a first oxidation process; removing the sacrificial oxide film in a wet etching process to form a second recessed region in the semiconductor substrate; and forming a field oxide film in a second oxidation process.
Claim 3
Dependent Claim
20 words
A method in accordance with claim 1, wherein said annealing step is carried out in an NH 3 gas atmosphere.
Claim 4
Dependent Claim
34 words
A method in accordance with claim 2, wherein said annealing step is carried out at about 800° to 1,000° C. and at a pressure of 10 to 100 torr for 0.5 to 2 hours.
Claim 5
Dependent Claim
21 words
A method in accordance with claim 1, wherein said selectively etching step is carried out until the nitrogen-accumulated layer is etched.
Claim 6
Dependent Claim
28 words
A method in accordance with claim 1, wherein said spacer is formed in the direction of said side wall, with its thickness ranging from 100 to 700 Å.
Claim 7
Dependent Claim
20 words
A method in accordance with claim 1, wherein said second recessed region has a depth of 100 to 500 Å.
Claim 8
Dependent Claim
23 words
A method in accordance with claim 1, wherein said first oxidation process is carried out at a temperature of 700° to 900° C.
Claim 9
Dependent Claim
22 words
A method in accordance with claim 7, wherein said sacrificial oxide film is formed at a thickness of 100 to 1,000 Å.
Claim 10
Dependent Claim
25 words
A method in accordance with claim 1, wherein said sacrificial oxide film is removed at a range of 80 to 100% of its total thickness.
Claim 11
Dependent Claim
19 words
A method in accordance with claim 1, wherein said oxidation-restraining layer and the spacer each comprise a nitride film.
Claim 12
Dependent Claim
15 words
A method in accordance with claim 10, wherein said buffer layer comprises an oxide film.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-02-16 | 2001-08-18 | 2002-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-02-16 | 2005-08-18 | 2006-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-02-16 | 2009-08-18 | 2010-02-17 | $7700.00 | Window Closed / Lapsed |