摘要 |
<p>To provide a gas field ion source having a high angular current density, the gas field ion source is configured such that at least a base body of an emitter tip configuring the gas field ion source is a single crystal metal, such that the apex of the emitter tip is formed into a pyramid shape or a cone shape having a single atom at the top, and such that the extraction voltage in the case of ionizing helium gas by the single atom is set to 10 kV or more.</p> |