Ion beam irradiation apparatus

An ion beam irradiation apparatus comprising:

• an ion source;
• a mass separator that sorts dopant ions having a specific mass number and valence from an ion beam extracted from the ion source, and that outputs the dopant ions;
• and
• an energy filter formed to define a beam passing region for allowing the ion beam to pass therethrough, and configured to have a given positive filter potential in response to application of a voltage thereto to separate passable ions capable of passing through the beam passing region and non-passable ions incapable of passing through the beam passing region, from each other by a difference in ion energy,
• wherein the given positive filter potential is set such that the dopant ions are included in the passable ions, and at least a portion of unwanted ions which cannot be separated from the dopant ions by the mass separator are included in the non-passable ions,
• wherein the energy filter comprises three or more electrodes each of which is formed with an opening for allowing the ion beam to pass therethrough, the three or more electrodes being provided along a traveling direction of the ion beam,
• wherein at least one of the three or more electrodes is configured to have the given positive filter potential, and each of the remaining electrodes is configured to have a potential less than the given positive filter potential, and wherein each of two of the electrodes disposed at respective opposite ends of the energy filter is configured to have an equal potential, and
• wherein the energy filter further comprises a profile control electrode configured to be applied with a profile control voltage for controlling a profile of the ion beam.