Research On High-field Asymmetric Waveform Ion Mobility Spectrometry Technology

Nowadays, advancement of science and technology contributes to global research onbiochemical weapon system and obtain some big achievement. Biochemical weapon bringsthreaten to people life while it leads to war victory. Frequent terrorist attack to civilian andincreasing environment pollution urge many countries to invest huge manpower and materialto study measurement technique to harmful gases having high sensitivity. Recent years,FAIMS, as an ion detection technology, rapidly developed and has been applied to variousareas, which has advantages such as brief operation, portability, quick reaction, low powerconsumption and high sensitivity.Firstly, the article introduces basic property of moving ion in electric field includingforces moving ion received and its effects, then briefly introduces performance index ofFAIMS and in detail analyzes ion movement circumstances in migration tube.Secondly, the article introduces design and processing of ion migration tube in terms ofthick film technology. For weakening the interference electric field makes to electrodes,migration tube with bucking electrodes has been designed. Furthermore, the article analyzesand compares the electric interference before and after bucking electrodes and introduces thedesign of controlling circuit.The article analyzes passing rate on ion in migration tube and the factor influencingpassing rate of ion in FAIMS migration tube mainly includes diffusion, compensation electricfield, polarization electric field and ion recombination. Through theoretical analysis, passingrate model in migration tube has been established.Finally, the article applied half-bridge inverter circuit to achieve the design of ahigh-field asymmetric square wave pulse power, which does electrical isolation withoptocoupler for the circuitry of drive control and MOSFET to avoid interference of theelectric field. That provides dynamic and static protection to MOSFET, guarantees safe operation of the circuit, improve the power performance and proposes optimum proposal onthe power output.