Pumping Mechanism and Development of a Getter Ion Pump

A getter ion pump has been often used for the evacuation of ultra-high vacuum mass spectrometer. However, it had been found previously that diode type getter ion pump exhiblts spontaneous periodic pressure fluctuations for argon. In order to stabilize these fluctuations for inert gases, a new modification of the construction of triode type getter ion pump in some different to the triode pumps already reported elsewhere has been made. Pumping mechanisms of diode pump and our triode pump have been examined by the use of radioactive Xe131m, and some problems in these pumps have been made clear.