Ion implantation apparatus and method of correcting deviation angle of ion beam

An ion implantation apparatus, wherein a traveling direction of an ion beam in a design is a Z direction, and two directions orthogonal to each other in a plane substantially orthogonal to the Z direction are an X direction and a Y direction, which irradiates a target with a ribbon-shaped ion beam having a width in the X direction larger than a width in the Y direction through scanning in the X direction or without scanning in the X direction, and comprises an ion beam deflector which deflects the ion beam in an energy state irradiating the target by a magnetic field or an electric field to separate the ion beam and a neutron from each other and a mask which is disposed between the ion beam deflector and the target and has an opening for passing the ion beam to form the ion beam, the apparatus comprising:

• an electric field lens, which comprises a plurality of electrodes opposed to each other in the Y direction with a space for passing the ion beam between the electrodes, is disposed on a downstream side of the ion beam deflector and an upstream side of the mask, and narrows the ion beam in the Y direction,
• wherein the electric field lens has an inlet electrode, an intermediate electrode, and an outlet electrode, which the electrodes are separately arranged in the traveling direction of the ion beam,
• each of the inlet electrode, the intermediate electrode, and the outlet electrode includes a pair of electrodes which are opposed to each other in the Y direction with a space for passing the ion beam between the electrodes and are substantially parallel to a plane of the ion beam, and the inlet electrode and the outlet electrode are electrically grounded, and
• a first direct-current voltage source and a second direct-current voltage source respectively apply independent direct-current voltages to the pair of electrodes of the intermediate electrode.