US3798752A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing a silicon gate insulated-gate field effect transistor
Assignee: NEC Corp
•
Filing: 1972-03-07
•
Granted: 1974-03-26
•
Expires: 1992-03-07
Abstract
Abstract A method is disclosed for fabricating an insulated gate field effect transistor having a silicon gate electrode. The silicon gate electrode is covered with a first insulating layer. That layer as well as the surfaces of the source and drain regions are thereafter covered with a second insulating layer. The second insulating layer is selectively removed to expose a portion of the first insulating layer covering the silicon gate electrode and a part of the surfaces of the source and drain regions. Source and drain electrodes are then respectively applied to the source and drain regions without the possibility of a drain-togate or source-to-gate short circuit.
Inventors
- 👤 S Fujimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:16
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D99/00; H10P; H10P10/00; H10P50/00; H10P50/69; H10P50/691
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
159 words
A method of producing an insulated-gate field effect transistor with a silicon layer as a gate electrode, said method comprising the steps of forming a gate insulator film on a part of the surface of a semiconductor substrate, forming a polycrystalline silicon layer on said gate insulator in the shape of said gate electrode, forming source and drain regions in said substrate, covering the exposed surfaces of said gate electrode with a first insulating layer, covering the surface of said substrate including the surface of said first insulating layer and the surface of each of said source and drain regions with a second insulating layer, selectively removing said second insulating layer to expose at least a part of the surface of said first insuLating layer and a part of the surface of each of said source and drain regions, and respectively attaching an electrode to said exposed part of the surface of each of said source and drain regions.
Claim 2
Independent Claim
159 words
A method of producing an insulated-gate field effect transistor with a silicon layer as a gate electrode, said method comprising the steps of forming a gate insulator film on a part of the surface of a semiconductor substrate, forming a polycrystalline silicon layer on said gate insulator in the shape of said gate electrode, forming source and drain regions in said substrate, covering the exposed surfaces of said gate electrode with a first insulating layer, covering the surface of said substrate including the surface of said first insulating layer and the surface of each of said source and drain regions with a second insulating layer, selectively removing said second insulating layer to expose at least a part of the surface of said first insuLating layer and a part of the surface of each of said source and drain regions, and respectively attaching an electrode to said exposed part of the surface of each of said source and drain regions.
Claim 3
Dependent Claim
44 words
The method of claim 1, in which said step of covering the exposed surface of said silicon layer with a first insulating layer is performed after said step of forming a polycrystalline silicon layer and before said step of formimg source and drain regions.
Claim 4
Dependent Claim
16 words
The method of claim 1, in which said first insulating layer is formed of silicon oxide.
Claim 5
Dependent Claim
21 words
The method of claim 3, in which said first insulating layer is formed by the anodic oxidation of said silicon layer.
Claim 6
Dependent Claim
59 words
The method of claim 3, further comprising the step of covering the surface of said semiconductor substrate except for the surface of said silicon layer with a silicon nitride layer before said step of covering the exposed surface of said silicon layer with a first insulating layer, said first insulating layer being formed by thermally oxidizing said silicon layer.
Claim 7
Dependent Claim
16 words
The method of claim 3, in which said second insulating layer is formed of silicon oxide.
Claim 8
Dependent Claim
16 words
The method of claim 3, in which said second insulating layer is formed of silicon nitride.
Claim 9
Dependent Claim
28 words
The method of claim 1, in which said first insulating layer is formed of silicon nitride or alumina and said second insulating layer is formed of silicon oxide.
Claim 10
Dependent Claim
15 words
The method of claim 8, in which said second insulating layer is formed of alumina.
References Cited (Backward Citations)
US3576478A
Cited
US3673471A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |