Patent US3850733A successfully refreshed from Google Patents.
EP0399261A2
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EP
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Band-to-band induced substrate hot electron injection
Assignee: Texas Instruments Inc
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Filing: 1990-05-04
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Granted: —
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Expires: 2010-05-04
Abstract
Abstract The described embodiments of the present invention are a method and structure for using band-to-band tunneling induced substrate hot electron injection. In the described embodiment, the channel region (32) of a floating gate transistor is doped to a heavily P typed doping region (32) which is the same doping type as the substrate (30). The gate (38) is brought up to the voltage sufficient to cause a heavily doped channel (32) to invert. A positive voltage is applied to the source (34) and drains (34) of the transistor thus causing the inverted electrons at the interface between the gate insulator (36) and the substrate (30) to be drawn away. This creates a deep depletion region, which causes band-to-band tunneling. With the removal of the inverted electrons, the band-to-band induced holes are driven away by the positive charge on the gate (38). These holes generate further electron hole pairs by impact ionization. A certain proportion of the electrons will have energy sufficient to overcome the energy barrier provided by the insulator (36) between the gate (38) and the substrate (30). This energy coupled with the field on the gate (38) causes electron flow from the substrate (30) into the gate (38).
Inventors
- 👤 Ih-Chin Chen
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 14:16
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/68; H10D30/681; H10D30/684; H10D30/683; H10D48/00; H10D48/01; H10D48/031; H10D48/032; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
173 words
A method of transporting charged particles across insulator, comprising the steps of; holding a semiconductor substrate at a reference potential, where said insulator is formed on the surface of said substrate; providing a field potential on a conductor formed on said insulator, where said insulator separates said substrate and said conductor, thereby establishing an electric field across said insulator and into said substrate, said electric field being large enough to induce band to band tunneling in said substrate; and providing a sink potential on a diffused region in said substrate, said diffused region having a conductivity type opposite to the conductivity of said substrate, said sink being close enough to said electric field to remove minority carries formed by said band to band tunneling at the interface between said insulator and said substrate, thereby causing the majority carriers generated by said band to band tunneling to create high energy carriers due to impact ionization, at least a portion of said high energy carriers having enough energy to cross said insulator into said conductor.
Claim 2
Independent Claim
173 words
A method of transporting charged particles across insulator, comprising the steps of; holding a semiconductor substrate at a reference potential, where said insulator is formed on the surface of said substrate; providing a field potential on a conductor formed on said insulator, where said insulator separates said substrate and said conductor, thereby establishing an electric field across said insulator and into said substrate, said electric field being large enough to induce band to band tunneling in said substrate; and providing a sink potential on a diffused region in said substrate, said diffused region having a conductivity type opposite to the conductivity of said substrate, said sink being close enough to said electric field to remove minority carries formed by said band to band tunneling at the interface between said insulator and said substrate, thereby causing the majority carriers generated by said band to band tunneling to create high energy carriers due to impact ionization, at least a portion of said high energy carriers having enough energy to cross said insulator into said conductor.
Claim 3
Dependent Claim
31 words
A method as in Claim 1 wherein said substrate at said interface is doped to a dopant concentration of approximately 8 × 10¹⁷ to 2 × 10¹⁸ atoms per cubic centimeter.
Claim 4
Dependent Claim
12 words
A method as in Claim 1 where said substrate comprises crystalline silicon.
Claim 5
Dependent Claim
12 words
A method as in Claim 1 where said insulator is silicon dioxide.
Claim 6
Dependent Claim
25 words
A method as in Claim 1 where said field is applied to said conductor through capacitive coupling and said conductor is surrounded by insulating material.
Claim 7
Independent Claim
88 words
A device comprising: a substrate, said substrate comprising a semiconductive material and said substrate having a first conductivity type; a drain region formed in said substrate having a conductivity type opposite said substrate; a first insulating layer formed on the surface of said substrate laterally adjacent to said drain region; a conductor formed on said first insulating layer; and a doped region having the same conductivity type as said substrate having a doping concentration at least one order of magnitude greater than the doping concentration of said substrate.
Claim 8
Independent Claim
88 words
A device comprising: a substrate, said substrate comprising a semiconductive material and said substrate having a first conductivity type; a drain region formed in said substrate having a conductivity type opposite said substrate; a first insulating layer formed on the surface of said substrate laterally adjacent to said drain region; a conductor formed on said first insulating layer; and a doped region having the same conductivity type as said substrate having a doping concentration at least one order of magnitude greater than the doping concentration of said substrate.
Claim 9
Dependent Claim
22 words
The device of Claim 6 where said doped region has a dopant concentration of approximately 8 × 10¹⁷ atoms per cubic centimeter.
Claim 10
Dependent Claim
11 words
The device of Claim 6 where said substrate comprises crystalline silicon.
Claim 11
Dependent Claim
38 words
The device of Claim 6 further comprising a drain region formed in said substrate having a conductivity type opposite to said substrate, said drain region formed laterally adjacent to said insulating layer and spaced from said source region.
Claim 12
Dependent Claim
12 words
The device of Claim 6 where said substrate is P conductivity type.
Claim 13
Dependent Claim
28 words
The device of Claim 6 further comprising; a second insulating layer formed on the surface of said conductor; and a control gate formed on said second insulating layer.
Claim 14
Dependent Claim
79 words
The device of Claim 6 further comprising: a second source region formed in said substrate; a second drain region separated flom said second source region defining a channel region therebetween; a gate insulating layer formed on the surface of said substrate above said channel region, said first conductive layer extending over said gate insulating layer; an interlevel insulating layer formed on the surface of said first conductive layer; and a channel control gate formed on said interlevel insulating layer.
Claim 15
Dependent Claim
63 words
The device of Claim 11 further comprising: a second source region formed in said substrate; a second drain region separated flom said second source region defining a channel region therebetween; a gate insulating layer formed on the surface of said substrate above said channel region, said first conductive layer, said second insulating layer; and said control gate extending over said gate insulating layer.
References Cited (Backward Citations)
No citation records indexed.
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