Development and Performance Study of 10^-9~10^-1Pa Wide-range Ionization Gauge

The measurement range of the hot cathode ionization gauge covers the pressure up to ultra-high vacuum.It is widely used in variety of vacuum facilities.According to the principle of ionization gauge,the residual ion current I_r⁺of ionization gauge is theoretically analyzed.Several effects,such as gas molecular thermal desorption,soft X-ray and electron stimulated desorption,are discussed.The gauge structure and preparation process were optimized,and the vacuum gauge was developed.The residual pressure is reduced lower than 2×10^-9Pa.A supporting electronic controller has been developed and built,and the lower limit of the low current measurement reaches 0.1 pA.The range of the ionization vacuum gauge varies from 1.26×10^-9~ 6.02×10^-1Pa,and the sensitivity fluctuation is less than ±11%.