Patent ID: 7791041

Claim:
An ion source which generates a ribbon-like ion beam having a dimension in a Y direction in a plane substantially orthogonal to a traveling direction larger than a dimension in a X direction substantially orthogonal to the Y direction, comprising: a plasma generating vessel which generates a plasma inside, serves as an anode, introduces a gas inside, and having an ion extraction port extending in the Y direction; a cathode which is provided with at least one side in the X direction of the plasma generating vessel and generates the plasma by ionizing the gas which is generated discharge inside the plasma generating vessel by emitting an electron into the plasma generating vessel; a reflecting electrode which is arranged at least on the other side in the X direction inside the plasma generating vessel opposite to the cathode, and is set to a negative potential or a floating potential with respect to the plasma generating vessel and reflects the electron inside the plasma generating vessel; and a plurality of electromagnets which respectively generate a magnetic field along the X direction inside the plasma generating vessel and are arranged in a plurality of stages along the Y direction.