| 摘要 |
PURPOSE:To prevent the reduction of exhaust rate by forming an anode in mesh shape, providing a getter filament made of an active metal that is heated by external current application and a rare gas induction pipe in a pump casing. CONSTITUTION:High voltage is applied between cathodes 2 and 2 and mesh-type anode 3. Since sputtered active material passes through the mesh without being interrupted by anode 3 and is made to adhere on the surface of the cathodes 2 uniformly and abundantly, the surface can be kept cleaner than that of the conventional cathode and at the same time, since the movement of gas particles can be performed through the mesh of the anode 3, the ion collection factor is also raised and exhaust efficiency is improved. When discharge-treatment and activation are carried out after a long-term use of a pump since rare gas can be guided directly through an induction pipe 5 provided in a casing 1, the pump can be discharge-treated without making the inner part of a vacuum chamber 10 exposed to high rare gas pressure by closing a partition valve 11, and it is convenient to use the pump. |
