基于等动量加速与场发射电子源的空间用微型飞行时间质谱计研究

For the scientific goals of future deep space explorations in our country, this project aims to develop miniature time-of-flight mass spectrometer with small size, light load, low power consumption, and high mass resolution. Traditional time-of-flight mass spectrometer (TOF-MS) is based on the principle of equal energy acceleration. Instead, this project puts forward a new-concept TOF-MS on the basis of equal momentum acceleration principle. Introduction of such a new concept is expected to greatly expand the mass number range of TOF-MS instruments, and significantly improve their mass resolution power. The key technology to attain this goal is to accelerate the gas ions using high-voltage pulses with short duration. Based on our previous accumulations in this area, in order to further compress the equipments’ volume and reduce their power consumption, this project is planned to use field-emission based ionization source, mainly to solve the instability and short-life problems of field emission cathode by using our novel patented technologies. We will learn from the NASA and ESA on their advanced experiences in developing miniature TOF-MS instruments for space applications in recent years, adopting coaxial structure in the main structure of the instrument, namely, the ionization source, ion reflector, and the ion detector are in coaxial structure. We will also use a large number of MEMS techniques in order to suppress the volume and mass of the instrument in the main structure, electronic control unit, and the other structural units. This project will develop momentum analyzer-based miniature TOF-MS prototype instruments with the key specifications meeting or exceeding the international advanced levels, then manage to apply these instruments in the institutes specialized in space technology researches, and at last exploit new application prospect in the fields such as environmental monitoring.

针对我国深空探测科学目标，本项目拟研制小体积、轻质量、低功耗、高分辨的空间用微型飞行时间质谱计。传统的飞行时间质谱计（TOF-MS）基于等能量加速原理。与此不同，在多年积累基础上，我们提出基于等动量加速原理的TOF-MS概念，预期将大大扩展仪器的质量数范围，明显提升仪器的分辨本领。其关键在于对离子的高压短脉冲加速。为减小仪器体积和功耗，还将采用场发射电离源方案，并采用全新的专利技术解决场发射阴极的不稳定和短寿命问题。仪器的主体结构借鉴NASA和ESA空间用微型TOF-MS的经验，采用电离源、离子反射镜、离子探测器三者同轴结构。大量采用MEMS工艺技术，缩减仪器主体结构、电子控制以及其它单元的尺寸和质量。本项目将研制出具有自主知识产权的基于动量加速和场发射电子源的TOF-MS仪器，其关键技术指标达到或超过国际先进水平，在空间技术研究单位推广应用，也在环保监测等领域开拓新的应用前景。