Numerical Simulation of a Metrological Ionization Vacuum Gauge Based on Carbon Nanotube Electron Source

The metrological ionization gauge realizes highly stable ultra-high vacuum measurements by controlling both the trajectories of electrons and kinetic energy in the ionization volume.A metrological ionization gauge based on carbon nanotube(CNT) electron source is designed, and a physical model is constructed to simulate the parameters of the electron passing efficiency, the electron transmission efficiency and the sensitivity. The effects of different electron emission distributions, main electrode voltages and fabrication tolerances on the three parameters were also analyzed.The theoretical sensitivity was 0.251 7 Pa^-1 with a standard deviation of 7.753 8×10^-5 Pa^-1.