Electron source, method for manufacturing same, and device provided with electron source

Patent metadata

Field	Value
Publication number	US-12014894-B2
Application number	US-202118258461-A
Country	US
Kind code	B2
Filing date	Dec 20, 2021
Priority date	Dec 25, 2020
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

A method for manufacturing an electron source includes steps of sandwiching a welding object in which a tip of an electron emission material and a tungsten filament overlap in direct contact between a pair of welding electrodes, and welding the tip and the tungsten filament by causing a current to flow while pressing forces are applied to the welding object by the pair of welding electrodes. A thickness of the welding object is within a range of 50 to 500 μm.

First claim

The invention claimed is:

1. A method for manufacturing an electron source, the method comprising steps of:
sandwiching a welding object in which a tip of an electron emission material and a tungsten filament overlap in direct contact between a pair of welding electrodes; and
welding the tip and the tungsten filament by causing a current to flow while pressing forces are applied to the welding object by the pair of welding electrodes,
wherein a thickness of the welding object is within a range of 50 to 500 μm.

2. The method according to claim 1 , wherein a cross-sectional shape of a part welded to the tungsten filament in the tip is a square shape or a rectangular shape in which a length of one side is 10 to 300 μm.

3. The method according to claim 1 , wherein the electron emission material is selected from the group consisting of LaB 6 , HfC, and an IrCe compound.

4. The method according to claim 1 , wherein the tungsten filament contains rhenium.

5. An electron source comprising:
a tip of an electron emission material;
a tungsten filament; and
a welding portion in which the tip and the tungsten filament are directly bonded,
wherein a thickness of the welding portion is 50 to 500 μm, and
wherein the electron emission material is selected from the group consisting of LaB 6 , HfC, and an IrCe compound.

6. An electron source comprising:
a tip of an electron emission material;
a tungsten filament; and
a welding portion in which the tip and the tungsten filament are directly bonded,
wherein a thickness of the welding portion is 50 to 500 μm,
wherein the tungsten filament contains rhenium.

7. A device comprising the electron source according to claim 5 .

8. A device comprising the electron source according to claim 6 .

Assignees

• Denka Company Ltd

Inventors

• Chatani Hiromitsu

Classifications

• H01J2237/06308

  Thermionic sources · CPC title

• H01J37/065 Primary

  Construction of guns or parts thereof (H01J37/067 - H01J37/077 take precedence) · CPC title

• H01J1/16

  characterised by the shape · CPC title

• H01J2201/196

  Emission assisted by other physical processes, e.g. field- or photo emission · CPC title

• H01J9/04

  of thermionic cathodes · CPC title