Yin Heyu, Mu Xiaoyi, Li Haitao, Liu Xiaowen, Mason Andrew J
Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48824, USA (
Apple Inc., 1 Infinite Loop, Cupertino, CA 95014, USA;
IEEE Sens J. 2018 Oct;18(19):7899-7906. doi: 10.1109/JSEN.2018.2863644. Epub 2018 Aug 6.
The growing demand for personal healthcare monitoring requires a challenging combination of performance, size, power, and cost that is difficult to achieve with existing gas sensor technologies. This paper presents a new CMOS monolithic gas sensor microsystem that meets these requirements through a unique combination of electrochemical readout circuits, post-CMOS planar electrodes, and room temperature ionic liquid (RTIL) sensing materials. The architecture and design of the CMOS-RTIL-based monolithic gas sensor are described. The monolithic device occupies less than 0.5mm per sensing channel and incorporates electrochemical biasing and readout functions with only 1.4mW of power consumption. Oxygen was tested as an example gas, and results show that the microsystem demonstrates a highly linear response (R = 0.995) over a 0 - 21% oxygen concentration range, with a limit of detection of 0.06% and a 1 second response time. Monolithic integration reduces manufacturing cost and is demonstrated to improve limits of detection by a factor of five compared to a hybrid implementation. The combined characteristics of this device offer an ideal platform for portable/wearable gas sensing in applications such as air pollutant monitoring.
对个人医疗保健监测的需求不断增长，这需要在性能、尺寸、功耗和成本方面实现具有挑战性的组合，而现有气体传感器技术很难做到这一点。本文介绍了一种新型的CMOS单片气体传感器微系统，该系统通过电化学读出电路、CMOS后平面电极和室温离子液体（RTIL）传感材料的独特组合来满足这些要求。描述了基于CMOS-RTIL的单片气体传感器的架构和设计。该单片器件每个传感通道占用面积小于0.5mm，并且仅消耗1.4mW的功耗就集成了电化学生物偏置和读出功能。以氧气作为示例气体进行测试，结果表明该微系统在0-21%的氧气浓度范围内呈现出高度线性响应（R=0.995），检测限为0.06%，响应时间为1秒。单片集成降低了制造成本，并且与混合实现方式相比，检测限提高了五倍。该器件的综合特性为空气污染物监测等应用中的便携式/可穿戴气体传感提供了理想平台。
