Significance and Difficulty of Precise Measurement of Micro-sputtering Ion Pump

Micro-sputter ion pump with pumping speed less than 1×10^-4 m³/s is widely used in the filed such as space payloads, electronic devices, scientific instruments and so on. The lower limit of existing vacuum pumping speed measurement standards is greater than 1×10^-2 m³/s, which cannot solve the urgent need of accurate measurement of minimum pumping speed. The main reasons that the lower limit for measurement is the pumping speed of the ionization vacuum gauge is on the magnitude of 10^-4~10^-5 m³/s, which is the same order of magnitude for the pumping speed of the micro vacuum pump, and the existing measurement methods can’t be applied to the measurement of minimum pumping speed. On the basis of discussing the importance and difficulty of the minimum pumping speed measurement of micro sputtering ion pump, the latest development of the measurement of the minimum pumping speed is investigated. The conception of the minimum pumping speed measurement is put forward, which can provide help for the accurate measurement of the minimum pumping speed of micro-sputtering ion pump.