Charged particle gun and charged particle beam device

A charged particle gun configured to irradiate a sample with a charged particle beam, the charged particle gun comprising:

• a charged particle beam source configured to emit the charged particle beam;
• a voltage circuit configured to supply a voltage to the charged particle beam source;
• a wiring configured to connect the charged particle beam source and the voltage circuit;
• a cover portion configured to cover the wiring;
• an extraction electrode configured to extract the charged particle beam from the charged particle beam source;
• and
• an acceleration electrode configured to accelerate the charged particle beam, wherein
• the voltage circuit includes a first voltage source and a second voltage source,
• the first voltage source and the second voltage source are disposed to output to the wiring an addition voltage obtained by adding an output voltage from the first voltage source to an output voltage from the second voltage source,
• the cover portion includes a first enclosure and a second enclosure,
• the first enclosure is configured to be connected to the extraction electrode and to an output terminal of the second voltage source, and
• the second enclosure is configured to be connected to the acceleration electrode and to a reference voltage of the voltage circuit.