Single walled carbon nanotube triode and methods of using same

Patent metadata

Field	Value
Publication number	US-10577246-B1
Application number	US-201916540318-A
Country	US
Kind code	B1
Filing date	Aug 14, 2019
Priority date	Jan 20, 2015
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

A carbon nanotube triode apparatus includes a plurality of Horizontally Aligned Single Wall Carbon Nano Tubes (HA-SWCNT disposed on an electrically insulating thermally conductive substrate. A first contact is disposed on the substrate and electrically coupled to a first end of the HA-SWCNT. A second contact is disposed on the substrate and separated from a second end of the HA-SWCNT by a gap. A gate terminal is coincident with a plane of the substrate.

First claim

What is claimed is:

1. A method of electrostatically and/or optically controlling field emission, using a carbon nanotube triode apparatus, said carbon nanotube triode apparatus comprising:
a plurality of Horizontally Aligned Single Wall Carbon Nano Tubes (HA-SWCNT) disposed on an electrically insulating thermally conductive layer of a substrate; a first contact disposed on the substrate and electrically coupled to a first end of the HA-SWCNT, wherein the first contact is disposed overlapping the first end of the HA-SWCNT in a view perpendicular to the electrically insulting and thermally conductive layer; a second contact disposed on the substrate, said second contact being entirely separated from the HA-SWCNT by a gap in the view perpendicular to the electrically insulting and thermally conductive layer; and a gate terminal coincident with a plane of the substrate below the electrically insulting and thermally conductive layer, said method comprising:
a) electrostatically controlling field emission by:
(i) applying a voltage difference across said first contact and said second contact, said voltage application comprising applying a higher voltage to said second contact than the voltage applied to said first contact, said voltage difference being sufficient to generate a field emission across said carbon nanotube triode apparatus's gap;
(ii) applying a higher voltage than applied to said second contact to said gate terminal, said voltage being applied to said gate terminal being sufficient to control the initiation of the field emission across said carbon nanotube triode apparatus's gap; and/or

b) optically controlling field emission by
(i) applying a voltage difference across said first contact and said second contact, said voltage application comprising applying a higher voltage to said second contact than the voltage applied to said first contact, said voltage difference being sufficient to generate a field emission across said carbon nanotube triode apparatus's gap;
(ii) generating a field emission of electrons by subjecting the portion of the HA-SWCNT adjacent to said gap with light; and
(iii) optionally applying a higher voltage than applied to said second contact to said gate terminal, said voltage being applied to said gate terminal being sufficient to control the initiation of the field emission across said carbon nanotube triode apparatus's gap.

2. The method of claim 1 , wherein said carbon nanotube triode apparatus's electrically insulating and thermally conductive layer of the substrate is selected from the group consisting of oxides, nitrides, or oxynitrides of: hafnium, zirconium, aluminum, titanium, yttrium, or lanthanum.

3. The method of claim 1 , wherein said carbon nanotube triode apparatus's electrically insulating and thermally conductive layer of the substrate comprises Si, a portion of the Si forms a SiO2 layer of approximately 100 nm.

4. The method of claim 2 , wherein said carbon nanotube triode apparatus's electrically insulating and thermally conductive layer of the substrate comprises Si, a portion of the Si forms a SiO2 layer of approximately 100 nm.

5. The method of claim 1 , wherein said carbon nanotube triode apparatus's gap is from greater than zero nm to about 60 nm.

6. The method of claim 2 , wherein said carbon nanotube triode apparatus's gap is from greater than zero nm to about 60 nm.

7. The method of claim 3 , wherein said carbon nanotube triode apparatus's gap is from greater than zero nm to about 60 nm.

8. The method of claim 1 , wherein said carbon nanotube triode apparatus's gap is from about 0.1 nm to about 30 nm.

9. The method of claim 2 , wherein said carbon nanotube triode apparatus's gap is from about 0.1 nm to about 30 nm.

10. The method of claim 3 , wherein said carbon nanotube triode apparatus's gap is from about 0.1 nm to about 30 nm.

11. The method of claim 1 , wherein said carbon nanotube triode apparatus's gap is from about 1 nm to about 30 nm.

12. The method of claim 2 , wherein said carbon nanotube triode apparatus's gap is from about 1 nm to about 30 nm.

13. The method of claim 3 , wherein said carbon nanotube triode apparatus's gap is from about 1 nm to about 30 nm.

14. The method of claim 1 , wherein said carbon nanotube triode apparatus's gap is from about 10 nm to about 30 nm.

15. The method of claim 2 , wherein said carbon nanotube triode apparatus's gap is from about 10 nm to about 30 nm.

16. The method of claim 3 , wherein said carbon nanotube triode apparatus's gap is from about 10 nm to about 30 nm.

17. The method of claim 1 , wherein said carbon nanotube triode apparatus's gap is from greater than zero nm to about 1 mm and said carbon nanotube triode apparatus's is disposed in an inert medium.

18. The method of claim 17 , wherein said inert medium is nitrogen or argon.

19. The method of claim 1 , wherein a portion of said carbon nanotube triode apparatus's HA-SWCNT is unsupported by the substrate.

Assignees

• Us Gov Air Force
• Us Air Force

Inventors

• Islam Ahmad Ehteshamul
• Maruyama Benji

Classifications

• H01J19/24

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

• H01J9/025 Primary

  of field emission cathodes · CPC title

• C01B2202/08

  Aligned nanotubes · CPC title

• C01B2202/02

  Single-walled nanotubes · CPC title

• C01B32/168

  After-treatment · CPC title