Liquid metal ion source and method for producing the same

摘要

A liquid metal ion source comprises a reservoir storing a metal to be ionized and a needle electrode to which the metal is fed from the reservoir wherein the size of small pits formed in at least a cone surface of the needle electrode is 0.1 mum-1.5 mum and the small pits exist in the cone surface of the needle electrode in a density of 5x104 number/mm2-5x106 number/mm2 the small pits being formed by chemically etching.