US4376336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for fabricating a semiconductor device
Assignee: Toshiba Corp
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Filing: 1981-08-06
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Granted: 1983-03-15
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Expires: 2001-08-06
Abstract
Abstract The invention provides a method for fabricating a semiconductor device comprising the steps of: forming an insulating layer on a semiconductor substrate; selectively forming an oxidation preventive film on the surface of said insulating layer; depositing polycrystalline silicon on the entire surface of said substrate including said oxidation preventive film; selectively etching said polycrystalline silicon so as to leave said polycrystalline silicon only around the sides of said oxidation preventive film by an etching method having a directivity perpendicular to the surface of said substrate; ion-implanting an impurity for preventing inversion in said substrate using as a mask said oxidation preventive film and said polycrystalline silicon remaining therearound; and forming a field insulator film including an oxide of said polycrystalline silicon by oxidizing the surface of said substrate. A higher integration and a higher reliability of elements may be attained according to the method of the invention.
Inventors
- 👤 Norio Endo
- 👤 Hisakazu Iizuka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:30
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P30/21; H10P30/212; H10P76/00; H10P76/40; H10P76/408; H10P76/4085; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0125; H10W10/0126; H10W10/10; H10W10/13
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
122 words
A method for fabricating a semiconductor device comprising the steps of: forming an insulating layer on a semiconductor substrate; selectively forming an oxidation preventive film on said insulating layer; depositing polycrystalline silicon on the entire surface of said substrate including said oxidation preventive film; selectively etching said polycrystalline silicon so as to leave said polycrystalline silicon only around the sides of said oxidation preventive film by an etching method having a directivity perpendicular to the surface of said substrate; ion-implanting an impurity for preventing inversion in said substrate using as a mask said oxidation preventive film and said polycrystalline silicon remaining therearound; and forming a field insulator film including an oxide of said polycrystalline silicon by oxidizing the surface of said substrate.
Claim 2
Independent Claim
122 words
A method for fabricating a semiconductor device comprising the steps of: forming an insulating layer on a semiconductor substrate; selectively forming an oxidation preventive film on said insulating layer; depositing polycrystalline silicon on the entire surface of said substrate including said oxidation preventive film; selectively etching said polycrystalline silicon so as to leave said polycrystalline silicon only around the sides of said oxidation preventive film by an etching method having a directivity perpendicular to the surface of said substrate; ion-implanting an impurity for preventing inversion in said substrate using as a mask said oxidation preventive film and said polycrystalline silicon remaining therearound; and forming a field insulator film including an oxide of said polycrystalline silicon by oxidizing the surface of said substrate.
Claim 3
Dependent Claim
43 words
A method according to claim 1, wherein the step of selectively forming on said insulating layer an oxidation preventive film having a silicon oxide film on the upper surface thereof is performed in place of the step of forming said oxidation preventive film.
Claim 4
Dependent Claim
43 words
A method according to claim 1, wherein the step of selectively forming an oxidation preventive film having a silicon oxide film on the upper surface and the side surfaces thereof is performed in place of the step of forming said oxidation preventive film.
Claim 5
Independent Claim
18 words
A method according to claims 1, 2 or 3, wherein said oxidation preventive film consists of silicon nitride.
Claim 6
Independent Claim
17 words
A method according to claims 1, 2 or 3, wherein said etching involves the reactive-ion etching process.
Claim 7
Independent Claim
21 words
A method according to claims 1, 2 or 3, wherein said semiconductor substrate comprises a silicon substrate of one conductivity type.
Claim 8
Independent Claim
19 words
A method according to claims 1, 2 or 3, wherein said field insulator film comprises a silicon oxide film.
Claim 9
Dependent Claim
49 words
A method according to claim 6, further comprising, after the step of forming said field insulator film, the steps of removing a laminate consisting of said insulating layer and said oxidation preventive film and forming regions of opposite conductivity type in parts of said silicon substrate below said laminate.
Claim 10
Dependent Claim
27 words
A method according to claim 8, wherein said regions of opposite conductivity type comprise a source region and a drain region of an MOS-type field effect transistor.
References Cited (Backward Citations)
US3873373A
Cited
US3913211A
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US4179311A
Cited
US4246044A
Cited
US4272308A
Cited
US4287661A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-14 | 1986-09-13 | 1987-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-14 | 1990-09-13 | 1991-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-14 | 1994-09-13 | 1995-03-15 | $7700.00 | Window Closed / Lapsed |