气体富集器是为了改善分析仪器的探测极限而设置在探头之前的一个采样和富集装置,采用MEMS技术制作的微型气体富集器与传统的富集器相比,由于热容量小,因而能在更小的功耗下获得更快的升温速率,从而显著地提高富集效率。该丈对MEMS微型气体富集器的研究现状进行了综述,重点从吸附面积、气流大小、温升快慢、流场设计等方面对富集器的各种结构进行了综合分析比较,并介绍了相控加热以及微阀集成两种技术提高富集率的基本原理。
The preconcentrator is a front-end sampling and concentrating device that can significantly improves the detection limit of a microanalytical system. The micromachined preconcentrators with reduced thermal mass can raise the temperature much faster at lower power compared with the conventional desorption tubes, thus realizing a much higher concentration factor. In this paper, the state-of-the-art of the microfabricated preconcentrators are systematically summarized, with especial emphasise on the structure of the micro-preconcentrators from the point of view of adsorption area, gas flux, temperature rising, fluid channel design, and so on. The principles of phased heater array and preconcentrator with integrated micro-valves are also introduced.