Field emission devices

Patent metadata

Field	Value
Publication number	US-11810774-B2
Application number	US-202117458158-A
Country	US
Kind code	B2
Filing date	Aug 26, 2021
Priority date	Aug 26, 2020
Publication date	Nov 7, 2023
Grant date	Nov 7, 2023

Abstract

A method for making field emission devices so that they have emitter tips in the form of a needle-like point with a width and length configured such that ratio of the width to the length ranges from about 0.001 to about 0.05, and associated methods for making the tips by 3-D printing.

First claim

The invention claimed is:

1. A method for making a field emission device, comprising the steps of:
providing an array of emitter tips; and
coating portions of the emitter tips with a conductive material by depositing the conductive material onto the emitter tips from one side only of the emitter tips at an angle of from about 30 degrees to about 60 degrees relative to the length axis of the emitter tips such that the conductive material is deposited onto the emitter tips in a sharp tip configuration in the form of a needle-like point with a width and length configured such that the ratio of the width to the length ranges from about 0.001 to about 0.05.

2. The method of claim 1 , wherein the array of emitter tips is formed by 3-D printing.

3. The method of claim 2 , wherein the 3-D printing is performed by one or more of fused deposition modeling, inkjet printing, stereolithography, and selective sintering.

4. The method of claim 2 , wherein the array of emitter tips formed by 3-D printing is made from one or more of carbon, metal, powder of nylon, graphite-infused nylon, aluminum-infused nylon and conductive resin.

5. The method of claim 1 , wherein in the array the emitters are identical to one another.

6. The method of claim 1 , wherein in the array the emitters are uniformly spaced apart.

7. The method of claim 1 , wherein in the array the emitters are not identical to one another.

8. The method of claim 1 , wherein in the array the emitters are not uniformly spaced apart.

9. The method of claim 1 , wherein the step of providing the array of emitter tips comprises providing the array of emitter tips from a soluble material, and the method further includes a step of removing portions of the soluble material after the step of coating portions of the emitter tips with a conductive material.

10. A method for making a field emission device, comprising the steps of:
providing an array of emitter tips; and
coating portions of the emitter tips with a conductive material such that the conductive material is deposited onto the emitter tips in a sharp tip configuration in the form of a needle-like point with a width and length configured such that ratio of the width to the length ranges from about 0.001 to about 0.05.

11. The method of claim 10 , wherein the array of emitter tips is formed by 3-D printing.

12. The method of claim 11 , wherein the 3-D printing is performed by one or more of fused deposition modeling, inkjet printing, stereolithography, and selective sintering.

13. The method of claim 11 , wherein the array of emitter tips formed by 3-D printing is made from one or more of carbon, metal, powder of nylon, graphite-infused nylon, aluminum-infused nylon and conductive resin.

14. The method of claim 10 , wherein in the array the emitters are identical to one another and uniformly positioned.

15. The method of claim 10 , wherein in the array the emitters are not identical to one another.

16. The method of claim 10 , wherein in the array the emitters are not uniformly positioned.

17. A method for making a field emission device, comprising the steps of:
providing an emitter tip by 3-D printing, wherein the emitter tip has a width and a length; and
configuring the emitter tip during printing such that the ratio of the width of the emitter tip to the length of the emitter tip ranges from about 0.001 to about 0.05.

18. The method of claim 17 , wherein the step of providing an emitter tip comprises providing an array of emitter tips with the ratio of the width to the length of each of the emitter tips ranging from about 0.001 to about 0.05.

19. The method of claim 17 , wherein the 3-D printing is performed by one or more of fused deposition modeling, inkjet printing, stereolithography, and selective sintering.

20. The method of claim 17 , wherein the emitter tip is made from one or more of carbon, metal, powder of nylon, graphite-infused nylon, aluminum-infused nylon and conductive resin.

Assignees

• US Govt as represented by Secretary of Air Force
• Us Gov Air Force

Inventors

• Connelly Joseph M
• Harris John R
• Lewellen John W

Classifications

• H01J9/025 Primary

  of field emission cathodes · CPC title

• H01J2209/012

  Coating · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• H01J2201/30415

  needle shaped · CPC title

• H01J2201/30426

  Coatings on the emitter surface, e.g. with low work function materials · CPC title