JP2969020B

PURPOSE:To miniaturize the device as a whole by providing a convergent lens between an accelerating tube and a mass analyzing system so as to converge ions on the stationary focal plane of the mass analyzing system. CONSTITUTION:Only an ion source 2 is provided in a high voltage terminal 1, and is directly connected to an accelerating tube 3. The accelerating tube 3 draws out ions vertically downward, and gives energy required for implantation. A Q-lens 4 is a single quadrupole of electrostatic type, and converges ion beams accelerated by adjusting voltage to efficiently pass the ion beams through a slit 6 combined with an analyzing magnet 5. Accordingly, mass resolution can be assured as well as shortening the distance between the magnet 5 and the slit 6. Since a deflecting electrode 8 can be of a multipole electrode type deflecting electrode and all the lower part from the lower part flange of the accelerating tube 3 are a ground side, a device as a whole can be miniaturized.