US4939559A
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Dual electron injector structures using a conductive oxide between injectors
Assignee: International Business Machines Corp
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Filing: 1986-04-01
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Granted: 1990-07-03
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Expires: 2006-04-01
Abstract
Abstract The present invention relates to DEIS (Dual Electron Injector Structure) EAROM (Electrically Alterable Read Only Memory) devices which utilize a silicon-rich, silicon dioxide insulator between injectors which has an excess of silicon therein which is less than the excess of silicon in the silicon rich, silicon dioxide injectors. The device does not depart in any way from known DEIS EAROM devices except that the insulator layer between the injectors is rendered conductive to a desired degree by causing a compound insulator like SiO 2 to be off-stoichiometry during deposition so that the resulting insulator becomes silicon rich. Alternatively, the insulator may be deposited together with another metal which renders the insulator conductive or a metallic specie may be added to the insulator by diffusion or ion implantation after the insulator is formed. The resulting conductive insulator provides a means for draining off trapped charge in the insulator resulting in a device of such improved cyclibility that the DEIS EAROM can be used as a Non-Volatile Random Access Memory (NVRAM) capable of from 10 8 to greater than 10 10 cycles before threshold collapse occurs. The conductive insulator is designed so that it is conductive only at high electric fields encountered during writing and erasing and highly blocking at low fields encountered during reading or storage operations.
Inventors
- 👤 Donelli J. DiMaria
- 👤 David W. Dong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:38
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/68; H10D30/681; H10D30/682
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
40 words
A dual electron injector structure comprising first, second and third vertically disposed insulator regions each containing excess conductive material sufficient to render said regions conductive said second region being less conductive than and contiguous with said first and third regions.
Claim 2
Dependent Claim
40 words
A dual electron injector structure comprising first, second and third vertically disposed insulator regions each containing excess conductive material sufficient to render said regions conductive said second region being less conductive than and contiguous with said first and third regions.
Claim 3
Dependent Claim
26 words
A dual electron injector structure according to claim 1 further including first and second conductive elements disposed in contact with said first and third regions, respectively.
Claim 4
Dependent Claim
15 words
A dual electron injector structure according to claim 1 wherein said insulator regions are cermets.
Claim 5
Dependent Claim
17 words
A dual electron injector structure according to claim 1 wherein said excess conductive material is a metal.
Claim 6
Dependent Claim
17 words
A dual electron injector structure according to claim 1 wherein said excess conductive material is a semimetal.
Claim 7
Dependent Claim
24 words
A dual electron injector structure according to claim 1 wherein said excess conductive material is distributed uniformly in said first, second and third regions.
Claim 8
Dependent Claim
24 words
A dual electron injector structure according to claim 1 wherein said excess conductive material is distributed nonuniformly in said first, second and third regions.
Claim 9
Dependent Claim
30 words
A dual electron injector structure according to claim 1 wherein said insulator regions are made of insulators selected from the group consisting of silicon dioxide, aluminum oxide and silicon nitride.
Claim 10
Dependent Claim
16 words
A dual electron injector structure according to claim 1 wherein said excess conductive material is silicon.
Claim 11
Dependent Claim
23 words
A dual electron injector structure according to claim 1 wherein said insulator regions are silicon dioxide and said excess conductive material is silicon.
Claim 12
Dependent Claim
63 words
A dual electron injector structure according to claim 10 wherein said first and third silicon dioxide regions contain excess silicon over that found in stoichiometric silicon dioxide 33% atomic silicon in an amount up to 60% atomic silicon and wherein said second silicon dioxide region contains excess silicon over that found in stoichiometric silicon dioxide in an amount up to 39% atomic silicon.
Claim 13
Dependent Claim
54 words
A dual electron injector structure comprising first, second and third vertically disposed insulator regions, said second region being sandwiched between said first and third regions each of said regions containing excess conductive material sufficient to render said regions conductive, said second region being less conductive than and contiguous with said first and third regions.
Claim 14
Dependent Claim
54 words
A dual electron injector structure comprising first, second and third vertically disposed insulator regions, said second region being sandwiched between said first and third regions each of said regions containing excess conductive material sufficient to render said regions conductive, said second region being less conductive than and contiguous with said first and third regions.
Claim 15
Dependent Claim
26 words
A dual electron injector structure according to claim 12 further including first and second conductive elements disposed in contact with said first and third regions, respectively.
Claim 16
Dependent Claim
15 words
A dual electron injector structure according to claim 12 wherein said insulator regions are cermets.
Claim 17
Dependent Claim
17 words
A dual electron injector structure according to claim 12 wherein said excess conductive material is a metal.
Claim 18
Dependent Claim
17 words
A dual electron injector structure according to claim 12 wherein said excess conductive material is a semimetal.
Claim 19
Dependent Claim
24 words
A dual electron injector structure according to claim 12 wherein said excess conductive material is distributed uniformly in said first, second and third regions.
Claim 20
Dependent Claim
24 words
A dual electron injector structure according to claim 12 wherein said excess conductive material is distributed nonuniformly in said first, second and third regions.
Claim 21
Dependent Claim
30 words
A dual electron injector structure according to claim 12 wherein said insulator regions are made of insulators selected from the group consisting of silicon dioxide, aluminum oxide and silicon nitride.
Claim 22
Dependent Claim
16 words
A dual electron injector structure according to claim 12 wherein said excess conductive material is silicon.
Claim 23
Dependent Claim
23 words
A dual electron injector structure according to claim 12 wherein said insulator, regions are silicon dioxide and said excess conductive material is silicon.
Claim 24
Dependent Claim
63 words
A dual electron injector structure according to claim 21 wherein said first and third silicon dioxide regions contain excess silicon over that found in stoichiometric silicon dioxide 33% atomic silicon in an amount up to 60% atomic silicon and wherein said second silicon dioxide region contains excess silicon over that found in stoichiometric silicon dioxide in an amount up to 39% atomic silicon.
Claim 25
Dependent Claim
98 words
A semiconductor memory device comprising a semiconductor substrate of one conductivity type having a pair of regions of opposite conductivity type disposed therein and forming a channel region therebetween; an insulating layer formed over said channel region, and a dual electron injector structure formed over said substrate said structure comprising first, second and third vertically disposed insulator regions, said second region being sandwiched between said first and third regions each of said regions containing excess conductive material sufficient to render said regions conductive, said second region being less conductive than and contiguous with said first and third regions.
Claim 26
Dependent Claim
98 words
A semiconductor memory device comprising a semiconductor substrate of one conductivity type having a pair of regions of opposite conductivity type disposed therein and forming a channel region therebetween; an insulating layer formed over said channel region, and a dual electron injector structure formed over said substrate said structure comprising first, second and third vertically disposed insulator regions, said second region being sandwiched between said first and third regions each of said regions containing excess conductive material sufficient to render said regions conductive, said second region being less conductive than and contiguous with said first and third regions.
Claim 27
Dependent Claim
23 words
A dual electron injector structure according to claim 23 further including a gate electrode and a floating gate electrode disposed over said substrate.
Claim 28
Dependent Claim
15 words
A dual electron injector structure according to claim 23 wherein said insulator regions are cermets.
Claim 29
Dependent Claim
17 words
A dual electron injector structure according to claim 23 wherein said excess conductive material is a metal.
Claim 30
Dependent Claim
17 words
A dual electron injector structure according to claim 23 wherein said excess conductive material is a semimetal.
Claim 31
Dependent Claim
24 words
A dual electron injector structure according to claim 23 wherein said excess conductive material is distributed uniformly in said first, second and third regions.
Claim 32
Dependent Claim
24 words
A dual electron injector structure according to claim 23 wherein said excess conductive material is distributed nonuniformly in said first, second and third regions.
Claim 33
Dependent Claim
30 words
A dual electron injector structure according to claim 23 wherein said insulator regions are made of insulators selected from the group consisting of silicon dioxide, aluminum oxide and silicon nitride.
Claim 34
Dependent Claim
16 words
A dual electron injector structure according to claim 23 wherein said excess conductive material is silicon.
Claim 35
Dependent Claim
23 words
A dual electron injector structure according to claim 23 wherein said insulator regions are silicon dioxide and said excess conductive material is silicon.
Claim 36
Dependent Claim
61 words
A dual electron injector structure according to claim 32 wherein said first and third dioxide regions contain excess silicon over that found in stoichiometric silicon dioxide 33% atomic silicon in an amount up to 60% atomic silicon and wherein said second silicon dioxide contains excess silicon over that found in stoichiometric silicon dioxide in an amount up to 39% atomic silicon.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-02 | 1994-01-01 | 1994-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-02 | 1998-01-01 | 1998-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-02 | 2002-01-01 | 2002-07-03 | $7700.00 | Window Closed / Lapsed |