Fold over emitter and collector field emission transistor

Patent metadata

Field	Value
Publication number	US-9941088-B2
Application number	US-201615192011-A
Country	US
Kind code	B2
Filing date	Jun 24, 2016
Priority date	Apr 13, 2015
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A field emission transistor includes a gate, a fold over emitter, and fold over collector. The emitter and the collector are separated from the gate by a void and are separated from a gate contact by gate contact dielectric. The void may be a vacuum, ambient air, or a gas. Respective ends of the emitter and the collector are separated by a gap. Electrons are drawn across gap from the emitter to the collector by an electrostatic field created when a voltage is applied to the gate. The emitter and collector include a first conductive portion substantially parallel with gate and a second conductive portion substantially perpendicular with gate. The second conductive portion may be formed by bending a segment of the first conductive portion. The second conductive portion is folded inward from the first conductive portion towards the gate. Respective second conductive portions are generally aligned.

First claim

The invention claimed is:

1. A field emission transistor comprising:
a trench formed within a dielectric layer;
a gate formed within the trench which is in electrical communication with a gate contact;
gate contact dielectric material surrounding the gate contact;
an emitter lining a first sidewall of the trench and comprising a first emitter portion adjacent to the gate contact dielectric material and a second emitter portion angled from the first emitter portion toward the gate;
a collector lining a second sidewall of the trench comprising, a first collector portion adjacent to the gate contact dielectric material and a second collector portion angled from the first collector portion toward the gate; and
wherein the emitter and collector are separated from the gate by a void.

2. The field emission transistor of claim 1 , wherein the first emitter portion and the first collector portion are substantially parallel to the gate.

3. The field emission transistor of claim 1 , wherein the second emitter portion and the second collector portion are substantially perpendicular to the gate.

4. The field emission transistor of claim 1 , wherein the second emitter portion is bent with respect to the first emitter portion and wherein the second collector portion is bent with respect to the first collector portion.

5. The field emission transistor of claim 1 , wherein the second emitter portion faces the second collector portion.

6. The field emission transistor of claim 5 , wherein second emitter portion is separated from the second collector portion by a gap that is less than the mean free path of elections in air.

7. The field emission transistor of claim 1 , further comprising:
an emitter contact in electrical communication with the first emitter portion, and;
a collector contact in electrical communication with the first collector portion.

8. The field emission transistor of claim 1 , wherein the second emitter portion is acutely angled from the first emitter portion toward the gate, and wherein the second collector portion is acutely angled from the first collector portion toward the gate.

9. The field emission transistor of claim 1 , wherein the void separates the first emitter portion, the second emitter portion, the first collector portion, and the second collector portion from the gate.

Assignees

• IBM

Inventors

• Briggs Benjamin D
• Clevenger Lawrence A
• Rizzolo Michael

Classifications

• G06F2111/20

  Configuration CAD, e.g. designing by assembling or positioning modules selected from libraries of predesigned modules · CPC title

• G06F30/327

  Logic synthesis; Behaviour synthesis, e.g. mapping logic, HDL to netlist, high-level language to RTL or netlist · CPC title

• H01J21/105 Primary

  with microengineered cathode and control electrodes, e.g. Spindt-type · CPC title

• H01J19/24

  Cold cathodes, e.g. field-emissive cathode · CPC title

• H01J9/025

  of field emission cathodes · CPC title