ゲッタ・イオンポンプのアルゴン不安定性の機構

抄録

Getter ion pumps with various types of anode cell exhibit spontaneous periodic pressure fluctuations (argon instability) in the clean up of argon, krypton, and xenon. In order to obtain further information on the mechanism of this argon instability, the locations of inert gases caught by the electrodes of the pump at various phases of the pressure fluctuations are determined by using the radioactive tracer Xe^131m, and the depth of erosion in the cathode is measured by means of a multiple-beam interferometer. From these experiments, it is found that the argon instability results from inert gases, which are released from strongley-eroded-regions being cleaned up at weaklyeroded region. The mechanism of argon instability is discussed from the viewpoints of the penetration of ions in metals and the sputtering of metals by ion bombardment.