US3660819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Floating gate transistor and method for charging and discharging same
Assignee: Intel Corp
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Filing: 1970-06-15
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Granted: 1972-05-02
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Expires: 1990-06-15
Abstract
Abstract A floating gate transistor comprising a floating silicon or metal gate in a field effect transistor which is particularly useful in a read-only memory is disclosed. The gate which is surrounded by an insulative material such as SiO2 is charged by transferring charged particles (i.e., electrons) across the insulation from the substrate during an avalanche (breakdown) condition in the source or drain junctions of the transistor.
Inventors
- 👤 Bentchkowsky D Frohman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:34
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/68; H10D30/681; H10D30/684; H10D30/686; H10D84/00; H10D84/40; H10D84/401; H10D84/403; H10D84/406; H10D99/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
125 words
A storage device comprising: a semiconductor body of a first conductivity type; a pair of spaced apart regions of opposite conductivity type to said first conductivity type, forming a pair of PN junctions in said body; a floating gate disposed spatially between said pair of spaced apart regions; an insulative layer between said body and said fLoating gate; insulative means covering said floating gate, said insulative means being free of any metallization employed primarily for charging said floating gate; means for applying a voltage to at least one of said spaced apart regions and said body of sufficient magnitude to cause an avalanche injection, thereby causing electrons to pass through said insulative layer onto said floating gate whereby said floating gate may be electrically charged.
Claim 2
Dependent Claim
125 words
A storage device comprising: a semiconductor body of a first conductivity type; a pair of spaced apart regions of opposite conductivity type to said first conductivity type, forming a pair of PN junctions in said body; a floating gate disposed spatially between said pair of spaced apart regions; an insulative layer between said body and said fLoating gate; insulative means covering said floating gate, said insulative means being free of any metallization employed primarily for charging said floating gate; means for applying a voltage to at least one of said spaced apart regions and said body of sufficient magnitude to cause an avalanche injection, thereby causing electrons to pass through said insulative layer onto said floating gate whereby said floating gate may be electrically charged.
Claim 3
Dependent Claim
18 words
The storage device defined in claim 1 wherein said insulative layer is at least approximately 500 A. thick.
Claim 4
Dependent Claim
16 words
The storage device defined in claim 1 wherein said first conductivity type is an N type.
Claim 5
Dependent Claim
16 words
The storage device defined in claim 2 wherein said first conductivity type is an N type.
Claim 6
Dependent Claim
13 words
The storage device defined in claim 4 wherein said floating gate comprises silicon.
Claim 7
Dependent Claim
22 words
The storage device defined in claim 5 wherein said body comprises silicon and said insulative layer and insulative means comprise silicon oxide.
Claim 8
Dependent Claim
20 words
The storage device defined in claim 6 including contact means for providing contact to said pair of spaced apart regions.
Claim 9
Dependent Claim
126 words
In a storage device comprising: a semiconductor substrate of a first conductivity type; a pair of spaced apart regions of opposite conductivity type, forming a pair of PN junctions in said substrate; a floating gate disposed spatially between said spaced apart regions; and insulative layer disposed between said substrate and said floating gate; and insulative means covering said floating gate, said insulative means being free from any metallization employed primarily for charging said floating gate; a method for placing an electrical charge on said gate comprising applying a voltage to at least one of said regions and said substrate of sufficient magnitude to cause an avalanche injection thereby causing electrons to pass through the insulation from said substrate to said floating gate to charge said gate.
Claim 10
Dependent Claim
126 words
In a storage device comprising: a semiconductor substrate of a first conductivity type; a pair of spaced apart regions of opposite conductivity type, forming a pair of PN junctions in said substrate; a floating gate disposed spatially between said spaced apart regions; and insulative layer disposed between said substrate and said floating gate; and insulative means covering said floating gate, said insulative means being free from any metallization employed primarily for charging said floating gate; a method for placing an electrical charge on said gate comprising applying a voltage to at least one of said regions and said substrate of sufficient magnitude to cause an avalanche injection thereby causing electrons to pass through the insulation from said substrate to said floating gate to charge said gate.
Claim 11
Dependent Claim
13 words
The method defined in claim 8 wherein said voltage is approximately 30 volts.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |