Two-dimensional graphene cold cathode, anode, and grid

Patent metadata

Field	Value
Publication number	US-10186394-B2
Application number	US-201715730212-A
Country	US
Kind code	B2
Filing date	Oct 11, 2017
Priority date	May 4, 2016
Publication date	Jan 22, 2019
Grant date	Jan 22, 2019

Abstract

In an embodiment, a method includes forming a first diamond layer on a substrate and inducing a layer of graphene from the first diamond layer by heating the substrate and the first diamond layer. The method includes forming a second diamond layer on top of the layer of graphene and applying a mask to the second diamond layer. The mask includes a shape of a cathode, an anode, and one or more grids. The method further includes forming a two-dimensional cold cathode, a two-dimensional anode, and one or more two-dimensional grids by reactive-ion electron-beam etching. Each of the two-dimensional cold cathode, the two-dimensional anode, and the one or more two-dimensional grids includes a portion of the first diamond layer, the graphene layer, and the second diamond layer such that the graphene layer is positioned between the first diamond layer and the second diamond layer.

First claim

The invention claimed is:

1. An apparatus, comprising:
a substrate;
a two-dimensional anode positioned on the substrate;
a two-dimensional cold cathode positioned on the substrate opposed to the two-dimensional anode; and
one or more two-dimensional grids each including a portion positioned on the substrate between the two-dimensional anode and the two-dimensional cold cathode;
wherein each of the two-dimensional anode, the two-dimensional cold cathode, and the one or more two-dimensional grids comprises:
a first diamond layer;
a second diamond layer; and
a layer of graphene induced from the first diamond layer, the layer of graphene positioned between the first diamond layer and the second diamond layer.

2. The apparatus of claim 1 , wherein the first diamond layer comprises a hexagonal diamond.

3. The apparatus of claim 1 , wherein the layer of graphene is induced from the first diamond layer by heating the substrate and the first diamond layer.

4. The apparatus of claim 3 , wherein the heating is performed at a temperature between 400 degrees Celsius and 500 degrees Celsius.

5. The apparatus of claim 3 , wherein the heating is performed at a temperature between 900 degrees Celsius and 1900 degrees Celsius.

6. The apparatus of claim 1 , wherein each of the two-dimensional anode, the two-dimensional cold cathode, and the one or more two-dimensional grids are formed by reactive-ion electron-beam etching.

7. The apparatus of claim 1 , wherein the two-dimensional cold cathode comprises a pointed tip and at least two round edges.

8. The apparatus of claim 1 , wherein the first diamond layer is formed using a coat of a poly(hydridocarbyne) layer that is heated in an inert atmosphere.

9. The apparatus of claim 8 , wherein the coat is heated at a temperature between 150 and 800 degrees Celsius.

10. The apparatus of claim 8 , wherein the coat is added to the substrate by spin-coating the substrate.

11. An apparatus, comprising:
a substrate;
a two-dimensional anode positioned on the substrate;
a two-dimensional cold cathode positioned on the substrate opposed to the two-dimensional anode; and
one or more two-dimensional grids each including a portion positioned on the substrate between the two-dimensional anode and the two-dimensional cold cathode;
wherein each of the two-dimensional anode, the two-dimensional cold cathode, and the one or more two-dimensional grids comprises:
a first silicon carbide layer;
a second silicon carbide layer; and
a layer of graphene induced from the first silicon carbide layer, the layer of graphene positioned between the first silicon carbide layer and the second silicon carbide layer.

12. The apparatus of claim 11 , wherein the layer of graphene is induced from the first silicon carbide layer by heating the substrate and the first silicon carbide layer.

13. The apparatus of claim 12 , wherein the heating is performed at a temperature between 1500 degrees Celsius and 1700 degrees Celsius.

14. The apparatus of claim 11 , wherein each edge of the two-dimensional anode comprises a round edge.

15. The apparatus of claim 11 , wherein the two-dimensional cold cathode comprises a pointed tip and a plurality of round edges.

16. The apparatus of claim 11 , wherein each of the two-dimensional anode, the two-dimensional cold cathode, and the one or more two-dimensional grids are formed by reactive-ion electron-beam etching.

17. The apparatus of claim 11 , wherein the first silicon carbide layer is formed using a coat of poly(methylsilyne) or poly(silyne-co-hydridocarbyne).

18. The apparatus of claim 17 , wherein the coat is added to the substrate by spin-coating the substrate.

19. The apparatus of claim 11 , wherein the second silicon carbide layer is formed from one of poly(methylsilyne) or poly(hydridocarbyne).

20. An apparatus, comprising:
a substrate;
a two-dimensional anode positioned on the substrate;
a two-dimensional cold cathode positioned on the substrate; and
one or more two-dimensional grids each including a portion positioned on the substrate;
wherein each of the two-dimensional anode, the two-dimensional cold cathode, and the one or more two-dimensional grids comprises a first diamond layer, a second diamond layer, and a layer of graphene positioned between the first diamond layer and the second diamond layer.

Assignees

• Lockheed Corp

Inventors

• Findley David Glen

Classifications

• H01J1/316

  having an electric field parallel to the surface, e.g. thin film cathodes · CPC title

• H01J1/3042 Primary

  microengineered, e.g. Spindt-type · CPC title

• H01J9/025 Primary

  of field emission cathodes · CPC title

• H01J1/3046 Primary

  Edge emitters · CPC title

• H01J2201/30457

  Diamond · CPC title