High brightness boron-containing electron beam emitters for use in a vacuum environment

Patent metadata

Field	Value
Publication number	US-9984846-B2
Application number	US-201615217158-A
Country	US
Kind code	B2
Filing date	Jul 22, 2016
Priority date	Jun 30, 2016
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

An emitter containing a metal boride material has an at least partly rounded tip with a radius of 1 μm or less. An electric field can be applied to the emitter and an electron beam is generated from the emitter. To form the emitter, material is removed from a single crystal rod to form an emitter containing a metal boride material having a rounded tip with a radius of 1 μm or less.

First claim

What is claimed is:

1. An apparatus comprising:
an emitter containing a metal boride material, wherein the emitter includes a frustoconical section with an at least partly rounded tip that is in the shape of a truncated sphere, and wherein the at least partly rounded tip has a radius to a curved outer surface of 1 μm or less.

2. The apparatus of claim 1 , wherein the metal boride material includes a species selected from the list consisting of an alkali metal, an alkaline earth metal, a transition metal, a lanthanide, and an actinide.

3. The apparatus of claim 1 , wherein the metal boride material is a metal hexaboride material.

4. The apparatus of claim 1 , wherein the metal boride material includes LaB 6 .

5. The apparatus of claim 1 , wherein the emitter has an emitting area of less than 1 mm 2 .

6. The apparatus of claim 1 , wherein the metal boride material has a <100> crystal orientation.

7. The apparatus of claim 1 , wherein the radius is 700 nm or less.

8. The apparatus of claim 1 , wherein the radius is 450 nm or less.

9. The apparatus of claim 1 , wherein the radius is 100 nm or less.

10. The apparatus of claim 1 , wherein the at least partly rounded tip includes a flat emitting facet.

11. The apparatus of claim 1 , wherein the emitter has an emitting area less than 1 μm 2 .

12. A method comprising:
providing an emitter containing a metal boride material, wherein the emitter includes a frustoconical section with an at least partly rounded tip that is in the shape of a truncated sphere, and wherein the at least partly rounded tip has a radius to a curved outer surface of 1 μm or less;
applying an electric field to the emitter; and
generating an electron beam from the emitter.

13. The method of claim 12 , wherein the generating occurs in cryogenic field emission mode.

14. The method of claim 12 , wherein the generating occurs in room temperature field emission mode.

15. The method of claim 12 , wherein the generating occurs in warm temperature field emission mode, wherein the warm temperature field emission mode operates at a temperature greater than ambient and below 1000 K.

16. The method of claim 12 , wherein the generating occurs in thermal field mode.

17. The method of claim 12 , wherein the generating occurs in photocathode mode.

18. The method of claim 12 , wherein the generating occurs at an operating pressure of 10 −9 Torr or less.

19. The method of claim 12 , wherein the generating occurs at an operating pressure of 10 −11 Torr or less.

20. A method comprising:
removing material from a single crystal rod to form an emitter containing a metal boride material, wherein the emitter includes a frustoconical section with an at least partly rounded tip that is in the shape of a truncated sphere, and wherein the at least partly rounded tip has a radius to a curved outer surface of 1 μm or less.

Assignees

• Kla Tencor Corp

Inventors

• Schultz William G
• Delgado Gildardo R
• Hill Frances
• Garcia Berrios Edgardo
• Garcia Rudy

Classifications

• H01J37/073

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

• H01J2209/0223

  Field emission cathodes · CPC title

• H01J9/025

  of field emission cathodes · CPC title

• H01J19/24

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

• H01J2201/30411

  conical shaped, e.g. Spindt type · CPC title