US4525811A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor memory and method of producing the same
Assignee: Toshiba Corp
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Filing: 1982-01-29
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Granted: 1985-06-25
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Expires: 2002-01-29
Abstract
Abstract A static RAM using a flip-flop circuit as a memory cell is disclosed. The gate oxide film of the MOS transistor for selecting the memory cell is thicker than the gate oxide film of the MOS transistor included in the peripheral circuit of the memory matrix.
Inventors
- 👤 Fujio Masuoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:30
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/34; G11C11/40; G11C11/41; G11C11/412; H; H10; H10B; H10B10/00; H10B10/12; H10B10/15; H10D; H10D64/00; H10D64/20; H10D64/27; H10D64/311; H10D64/411; H10D64/511; H10D64/514; Y; Y10; Y10S; Y10S257/00; Y10S257/903; Y10S438/00; Y10S438/981
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
An integrated static RAM, comprising a flip-flop circuit constituting a memory cell, a MOS transistor for selecting the memory cell, and a peripheral circuit formed in a substrate in which is formed a memory matrix, wherein the gate oxide film of the MOS transistor for selecting the memory cell is thicker than the gate oxide film of the MOS transistor included in the peripheral circuit.
Claim 2
Dependent Claim
65 words
An integrated static RAM, comprising a flip-flop circuit constituting a memory cell, a MOS transistor for selecting the memory cell, and a peripheral circuit formed in a substrate in which is formed a memory matrix, wherein the gate oxide film of the MOS transistor for selecting the memory cell is thicker than the gate oxide film of the MOS transistor included in the peripheral circuit.
Claim 3
Dependent Claim
37 words
The integrated static RAM according to claim 1, wherein the flip-flop circuit is formed of cross-coupled first and second inverters each consisting of a load resistor and a driving transistor connected in series to the load resistor.
Claim 4
Dependent Claim
21 words
The integrated static RAM according to claim 1, wherein the flip-flop circuit is formed of cross-coupled first and second C-MOS inverters.
Claim 5
Dependent Claim
37 words
The integrated static RAM according to claim 1, wherein polysilicon gates formed in a single step are included in the MOS transistor for selecting the memory cell and the MOS transistor included in the peripheral circuit, respectively.
Claim 6
Dependent Claim
43 words
The integrated static RAM according to claim 1, wherein the MOS transistor for selecting the memory cell comprises a first polysilicon gate, and the MOS transistor included in the peripheral circuit comprises a second polysilicon gate formed separately from the first polysilicon gate.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |