Design and Fabrication of Miniature FAIMS Biochemical Sensor
A novel biochemical sensor was designed based on FAIMS(high field asymmetric waveform ion mobility spectrometry) theory.The sample ions were created at ambient pressure by VUV lamp ion source with photon discharge of 10.6 eV in power and 116.5 nm wave length.The drift tube was composed of two copper planar electrodes with the volume of 10 mmx10 mmx1 mm.A high field asymmetric rectangular waveform power was designed to provide a RF voltage(the maximum voltage of +1 180 V and the minimum voltage of 480 V) at the frequency of 189 kHz with the duty cycle of 30%.Acetone was adopted as the experiment sample and FAIMS MS technology was used to test the performance of biochemical sensor.Experimental results show that ions can be separated and filtrated by the biochemical sensor based on FAIMS theory.FAIMS simulation results based on the SIMION software were in agreement with the experimental results.Finally,the miniature FAIMS sensor chip based on micro electro mechanical system(MEMS) technology was fabricated with inductively coupled plasma(ICP) etching on two sides of the silicon and double silicon glass bonding,which was investigated with high field asymmetric rectangular waveform power with the peak voltage of 364 V at the frequency of 2 MHz and the duty cycle of 30%.Under the conditions of the carrier gas flow rate of 80 L/h and the compensation voltage sweeping from 10 V to 3 V at 0.1 V step,FAIMS spectra of acetone were acquired and the performance of the chip was verified.