CALIBRATION OF EXTREMELY HIGH VACUUM IONIZATION GAUGE

Two inverted magnetron cold cathode ionization gauges and one hot cathode ionization gauge were calibrated against a（extremely high vacuum） XHV calibration apparatus over the range 10^-9 Pa to 10^-1Pa with gas of N₂.The results showed that all gauges had better repeatability.Nevertheless,as for a whole measurement course,the correction factor and sensitivity were strongly pressure dependent.Therefore,to ensure accurate pressure measurement,it is necessary to calibrate these XHV ionization gauges accurately for reliability of the application in XHV.