Abstract: A method for forming a silicon on insulator substrate includes the step of dissociating a plasma of molecules including at least any one of oxygen and nitrogen to obtain ions. The ions are accelerated by passage through gaps between acceleration electrodes at a predetermined acceleration energy for irradiation of the accelerated ions onto a silicon substrate which is heated to form an insulation film within the silicon substrate.

Abstract: A method for forming a silicon on insulator substrate includes the step of dissociating a plasma of molecules including at least any one of oxygen and nitrogen to obtain ions. The ions are accelerated by passage through gaps between acceleration electrodes at a predetermined acceleration energy for irradiation of the accelerated ions onto a silicon substrate which is heated to form an insulation film within the silicon substrate.

Abstract: A large-area ion beam having a one-directionally long section is generated in a magnetically shielded ion source. The ion beam is bent evenly to form a large center angle of about 90 degrees in the direction of the short side by a window/frame type magnet having a large gap and having left and right frames each wound with a plurality of coils. Then, the ion beam is made to pass through a slit plate having a one-directionally long opening so that unnecessary ions are removed. The ion beam is then radiated onto a subject which makes a translational motion in the direction of the short side of the beam.

Abstract: An ion source for producing wide, large area type ion beams with a mass-separation device. Four, five six or so electrode plates with ion holes at the same positions are installed at the outlet of the ion source. Second or third one of the electrodes has Wien filters at the ion holes. The Wien filter has permanent magnets and electrodes for producing a magnetic field and an electric field perpendicular to the axial direction of the ion holes. Ion beams which have not been accelerated so fast are separated by mass by the Wien filter. Low kinetic energy of ions alleviates the strength of the magnetic field and the electric field. Wide, large area type ion beams without impurities are obtained.