Spatter ion pump

A sputter ion pump comprising an anode electrode and a cathode electrode arranged within a vacuum chamber, in which said vacuum chamber high voltage is applied between the anode and cathode electrode so that (a) electrons are spirally moved by means of a magnetic field, (b) residual gas molecules in the vacuum chamber are collided with electrons that are spirally moving and are ionized, (c) the ionized molecules sputter the cathode electrode to activate surfaces thereof, and (d) thus the surfaces of the cathode electrode which are activated and surfaces of the anode electrode adsorb or catch the gas molecules, thereby performing an evacuation,

• wherein
• (a) the vacuum chamber includes an inner wall having a cylindrical section which is formed to be rugged in a cross section to define outer recesses and inner recesses and to form the cathode electrode,
• (b) said outer recesses of the rugged cylindrical section contain a plurality of permanent magnets each having an identical shape and characteristic with their magnetic poles being directed to a same direction,
• (c) said inner recesses of the rugged cylindrical section contain a plurality of cylindrical anode electrode members paced from the vacuum chamber inner wall, the permanent magnets and the anode electrode members are arranged with equal spacing in a symmetrical configuration against a center axis of the pump, and
• (d) a cylindrical shield member having a peripheral portion provided with evacuating bores is provided coaxially to the permanent magnets and anode electrode members.