US3829888A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device and the method of making the same
Assignee: Hitachi Ltd
•
Filing: 1972-01-04
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Granted: 1974-08-13
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Expires: 1992-01-04
Abstract
Abstract A semiconductor device comprising a p type semiconductor substrate including an n channel depletion mode metal-oxidesemiconductor field effect transistor provided with a gate insulating double layer formed of a silicon oxide layer and a phosphosilicate glass layer and an n channel enhancement mode metal-oxide-semiconductor field effect transistor provided with a gate insulating double layer formed of a silicon oxide layer and an alumina layer, the portions of the semiconductor substrate other than those where the field effect transistors are formed being provided with a double layer of a silicon oxide layer and an alumina layer, or of an alumina layer and a phosphosilicate glass layer.
Inventors
- 👤 N Hashimoto
- 👤 T Masuhara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:47
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/80; H10D84/82; H10D84/83; H10D84/84; H10D84/8314; H10D99/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
26 words
A semiconductor device according to claim 1, wherein the thickness of said first gate insulating layer is in a range of from 500 to 1,500 A.
Claim 2
Dependent Claim
27 words
A semiconductor device according to claim 1, wherein the phosphorus concentration in said phospho-silicate glass layer is in a range of from 4 to 10 mol percent.
Claim 3
Dependent Claim
27 words
A semiconductor device according to claim 2, wherein the phosphorus concentration in said phospho-silicate glass layer is in a range of from 4 to 10 mol percent.
References Cited (Backward Citations)
US3502950A
Cited
US3632438A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-12 | 1978-02-11 | 1978-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-12 | 1982-02-11 | 1982-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-12 | 1986-02-11 | 1986-08-13 | $7700.00 | Window Closed / Lapsed |