Gas cluster ion beam apparatus

A gas cluster ion beam apparatus comprising:

• a high voltage power supply that generates a positive high voltage,
• a cluster generation chamber that generates a neutral gas cluster beam of gas atoms or gas molecules by injecting high-pressure gas through a nozzle in a vacuum,
• a skimmer that skims a cluster beam from a central region in the neutral gas cluster beam,
• an ionizer that includes a thermal filament generating ionizing thermal electrons and an anode rod to which an electron acceleration voltage is applied to accelerate the ionizing thermal electrons in a conductive housing to which the positive high voltage is applied, and generates cluster ions by impacting ionization of the ionizing thermal electrons to be accelerated with the cluster beam introduced into the conductive housing through the skimmer,
• a beam transport system that extracts the cluster ions from the ionizer as a gas cluster ion beam by a potential difference between an acceleration electrode provided at an outlet of the conductive housing and to which the positive high voltage is applied and an extraction electrode provided downstream of the acceleration electrode, and irradiates the gas cluster ion beam onto an irradiated substrate placed in a vacuum vessel for an irradiation chamber through one or more electrostatic lenses to which the positive high voltage is applied from the high voltage power supply,
• a high voltage stage being in a state to which the positive high voltage is applied and including a thermal filament power supply that supplies a heating current to the thermal filament and an ionizing power supply that applies the electron acceleration voltage to the anode rod to which the positive high voltage is applied, and
• a switching circuit (SWC) including a switching device provided in a power supply line between the ionizing power supply and the anode rod,
• wherein the gas cluster ion beam can be intermittently irradiated onto the irradiated substrate by which the switching circuit controls the switching device to be turned on and off.