US3590272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mis solid-state memory elements unitizing stable and reproducible charges in an insulating layer
Assignee: Westinghouse Electric Corp
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Filing: 1968-09-25
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Granted: 1971-06-29
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Expires: 1988-09-25
Abstract
Abstract A solid state memory element next provided in an MIS structure. Charges in the insulator layer are reproducibly and stably controlled with respect to bias potential applied across the metal and semiconductor layers. The direction of the bias potential variation is of a polarity to effect turn on of Pchannel MIS transistors. In a preferred form the memory element employs as the insulator a first layer of silicon dioxide next to the semiconductor, a layer of silicon nitride, and a second layer of silicon dioxide.
Inventors
- 👤 Belur Venkatachar Keshavan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:56
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/353; H03K3/356; H03K3/356008; G; G11; G11C; G11C16/00; G11C16/02; G11C16/04; G11C16/0466; H10; H10D; H10D30/00; H10D30/60; H10D30/69
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
124 words
The subject matter of claim 1 wherein: said insulator characteristic curve includes a first portion of substantially constant net insulator charger for negatively increasing VMS down to a critical value (VC) of VMS, a second portion of substantially linearly increasing net insulator charge with negatively increasing VMS, relative to VC, to an arbitrary maximum negative value (max. VMS) of VMS below the breakdown voltage of said insulator layer, a third portion of substantially constant net insulator charge for more positive, and less negative, VMS compared with maximum VMS up to a positive critical value (VC ) of VMS, a fourth portion of decreasing net insulator charger with more positive VMS than VC until the net insulator charge is the same as said first portion.
Claim 2
Dependent Claim
25 words
The subject matter of claim 1 wherein: said semiconductor body includes at least one means electrically responsive to changes in the charge in said insulator.
Claim 3
Dependent Claim
94 words
The subject matter of claim 3 wherein: said semiconductor body includes first and second regions in said surface forming first and second PN junction with the underlying portion of said body; said insulator layer covers at least a portion of said surface between said first and second regions; and metal electrode layer covers at least a portion of said insulator layer that covers said portion of said surface; means to make electrical contact to each of said first and second regions being controllable in accordance with the net insulator charge in said insulator layer.
Claim 4
Dependent Claim
53 words
The subject matter of claim 1 wherein: said semiconductor body is of silicon, said first layer has a thickness of from about 50 Angstroms to about 500 Angstroms, said second layer has a thickness of from about 50 Angstroms to about 1,000 Angstroms, and said third layer is thinner than said first layer.
Claim 5
Dependent Claim
81 words
The subject matter of claim 1 wherein: said first layer portion adjacent said semiconductor has a first dielectric constant and is substantially free of carrier traps, said second layer portion on said first layer portion has a second dielectric constant greater than said first dielectric constant by at least a factor of two and has deep carrier traps, and said third layer portion has a third dielectric constant less than said second dielectric constant by at least a factor of two.
References Cited (Backward Citations)
FR1452389A
Cited
US3475234A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |