PURPOSE: To always obtain a stable ion beam for various operating conditions without regard to or not to use an exciting coil as a magnetic field generating means by providing a magnetic substance driving mechanism able to adjust the magnetic field intensity or distribution in a discharge chamber.
CONSTITUTION: Microwaves generated in a microwave generating source and passed through a wave guide 2 are introduced into a discharge chamber 1 constructed between discharge electrodes 5, 5 through a dielectric 4 such as boron nitride placed in vacuum, to generate a strong microwave electric field. In addition, in order to apply a magnetic field perpendicular to the microwave electric field in the discharge chamber 1, permanent magnets 7 are provided outside of the discharge chamber 1. Here, a magnetic substance driving mechanism 11 is provided to enable to control positions of the permanent magnets 7 from outside. Thereby even when no exciting coil is used, the magnetic field intensity or distribution in the discharge chamber 1 can be adjusted to obtain a stable ion beam.
SAKUMICHI KUNIYUKI
TOKIKUCHI KATSUMI
SEKI TAKAYOSHI
IGA TAKASHI
