US Patent 11361934 Ion source device

There is provided an ion source device including a pair of first electrodes for emitting an electron, a second electrode that defines a region in which the electron is enclosed and to which raw material source gas is supplied, between the pair of first electrodes, and that has a hole portion through which an ion generated by collision between the electron and the material gas is extruded, an extraction electrode disposed apart from the second electrode along an extraction direction of the ion extracted from the second electrode so that a potential difference is formed between the second electrode and the extraction electrode, and an intermediate electrode disposed between the second electrode and the extraction electrode. A first potential difference between the second electrode and the intermediate electrode is greater than a second potential difference between the second electrode and the extraction electrode.