Design of a Controllable Sampling System for Gas Mass Spectrometry Analysis with the Pressure Range of (10–10⁵) Pa

To address the need for gas sampling of atmospheric and vacuum low-pressure gases in applications such as semiconductor manufacturing and aerospace engineering, this paper presents a controllable gas sampling system designed for mass spectrometry analysis in the pressure range of (10～10⁵) Pa. The system comprises a vacuum pumping module, a throttling sampling module, a vacuum measurement module, a temperature control module, and a data acquisition and control module. By employing a two-stage controllable pressure attenuation through a capillary sampling tube and a piezoelectric micro-regulating valve, combined with flow control using two orifice conductance elements, the system is capable of stably collecting gas samples under various pressure conditions. Experimental result demonstrates that within the sampling gas pressure range of (10～1×10⁵) Pa, the system can maintain the pressure in the mass spectrometry chamber within the range of (1×10⁻⁴～1×10⁻³) Pa. The system can be coupled with various types of mass spectrometers, providing a reliable sampling solution for mass spectrometry analysis over a wide pressure range.