Silicon electron emitter designs

Patent metadata

Field	Value
Publication number	US-10607806-B2
Application number	US-201816153103-A
Country	US
Kind code	B2
Filing date	Oct 5, 2018
Priority date	Oct 10, 2017
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

Electron source designs are disclosed. The emitter structure, which may be silicon, has a layer on it. The layer may be graphene or a photoemissive material, such as an alkali halide. An additional layer between the emitter structure and the layer or a protective layer on the layer can be included. Methods of operation and methods of manufacturing also are disclosed.

First claim

What is claimed is:

1. An electron source comprising:
an emitter structure that includes silicon;
a layer disposed on an outer surface of the emitter structure, wherein the layer includes or a photoemissive material, wherein the photoemissive material is an alkali halide, and wherein the alkali halide includes CsI, CsBr, or CsTe.

2. The electron source of claim 1 , further comprising a metal layer disposed between the emitter structure and the layer.

3. The electron source of claim 1 , further comprising a protective coating disposed on the layer.

4. The electron source of claim 1 , wherein the layer has a thickness from 0.1 nm to 500 nm.

5. A plurality of the electron sources of claim 1 , wherein the plurality of the electron sources forms an array.

6. The electron source of claim 1 , wherein the emitter structure has a diameter from 1 nm to 30 nm.

7. The electron source of claim 1 , wherein the emitter structure defines a tip with a radius from 5 nm to 20 nm.

8. A method comprising:
emitting electrons from an electron source comprising an emitter structure that includes silicon and a layer disposed on an outer surface of the emitter structure, wherein the layer includes a photoemissive material, wherein the photoemissive material is an alkali halide, and wherein the alkali halide includes CsI, CsBr, or CsTe.

9. The method of claim 8 , wherein the emitting occurs in a vacuum from 10 −10 Torr to 10 −12 Torr.

10. The method of claim 8 , wherein the emitting occurs at room temperature.

11. The method of claim 8 , wherein the emitting is cold field emission.

12. The method of claim 8 , wherein the emitting occurs at a temperature greater than room temperature and less than 500° C.

13. The method of claim 8 , wherein the emitting includes both field emission and photoemission.

14. A method of forming an electron source comprising:
etching an emitter structure from a silicon source; and
depositing a layer on an outer surface of the emitter structure, wherein the layer includes a photoemissive material, wherein the photoemissive material is an alkali halide, and wherein the alkali halide includes CsI, CsBr, or CsTe.

15. The method of claim 14 , further comprising depositing a metal layer on the outer surface of the emitter structure prior to depositing the layer.

16. The method of claim 14 , further comprising depositing a protective coating on the layer.

Assignees

• Kla Tencor Corp

Inventors

• Hill Frances
• Delgado Gildardo R
• Garcia Rudy F
• Romero Michael E
• Ioakeimidi Katerina

Classifications

• H10P72/0616

  Monitoring of warpages, curvatures, damages, defects or the like · CPC title

• H01J40/06

  Photo-emissive cathodes · CPC title

• H01J40/18

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• H01J37/073 Primary

  Electron guns using field emission, photo emission, or secondary emission electron sources · CPC title

• H01J2237/24521

  Beam diameter · CPC title