基于高场非对称波形离子迁移谱原理设计了一种由离子源,迁移区和检测器3部分组成的生化传感器。传感器采用真空紫外灯作离子源,高纯氮(99.999%)为载气,在常压下工作。加工了两种由两平行金属极板组成的迁移区,一种由两平板铜块组成,尺寸为25 mm×10 mm×1 mm;另外一种由微机电(MEMS )工艺加工,尺寸为20 mm×10 mm×1.5 mm。MEMS工艺加工的迁移区间距为1.5 mm,电场强度＜10 000 V/cm,不能过滤丙酮离子;铜块迁移区间距为1 mm,电场强度＞10 000 V/cm。当方波非对称射频电压峰峰值为1 600 V,频率为195.8 kHz,占空比为30%,补偿电压为-8.63 V时,采用平板铜块迁移区实现了丙酮离子的位移补偿,实验结果验证了传感器的性能。

A novel biochemcal sensor based on a high-Field Asymmetric Ion Mobility Spectrometry(FAIMS) theory is fabricated and characterized,which is mainly composed of an ionization source,a drift tube and a detector. By taking a VUV lamp as the ionization source and choosing an acetone with nitrogen (99.999%) as the carrier gas,the biochemical sensor works at ambient pressure.Moreover,two kinds of drift tubes consisting of two parallel plate electrodes are fabricated. One drift tube with the dimension of 25 mm×10 mm×1 mm is composed of two copper planar electrodes, the other with the dimension of 20 mm×10 mm×1.5 mm is fabricated by Micro Electro-Mechanical System(MEMS ) technology. For the former,the gap between the two drift tubes is 1 mm and the electrical field is above 10 000 V/cm;but for the latter,the gap between MEMS drift tube is 1.5 mm and the electrical field is less than 10 000 V/cm,which can not separate the acctone. With a peak-peak of rectangular asymmetric waveform voltage up to 1 600 V,a frequency of 195.8 kHz,a duty cycle of 30% and a compenstaion voltage of -8.63 V,the acetone displacement is compensated and the sensor ability to separate ions is demonstrated by an experiment using the planar copper drift tube.