Electron source, manufacturing method therefor, and device comprising electron source

A method for manufacturing an electron source,

• the electron source comprising:
• a support needle having a distal end;
• a chip of an electron emitting material having first and second end portions;
• and
• a joint configured to fix the first end portion of the chip to the distal end of the support needle,
• wherein the first end portion of the chip has a first surface and a second surface which form an angle of 10 to 90°,
• the method comprising steps of:
• (A) cutting out a chip of an electron emitting material from a block of the electron emitting material;
• (B) fixing a first end portion of the chip to a distal end of a support needle;
• and
• (C) sharpening a second end portion of the chip fixed to the distal end, wherein the step (A) includes:
• (a1) forming a first groove constituting a first surface of the chip in the block by irradiating a surface of the block with an ion beam;
• and
• (a2) forming a second groove constituting a second surface of the chip in the block by irradiating the surface of the block with an ion beam,
• the first end portion of the chip has the first surface and the second surface forming an angle of 10 to 90°, wherein the first surface and the second surface are formed such that the distance between the first surface and the second surface becomes closer as it goes from the second end portion of the chip towards the first end portion;
• and
• the step (B) includes forming a joint between the distal end of the support needle and the first end portion of the chip.