Quad-cantilever microsensors with a low-cost single-sided micro-machining technique for trace chemical vapor detection

被引：13

作者：

Yang, Yongliang ^{[1
]}

Chen, Ying ^{[1
]}

Xu, Pengcheng ^{[1
]}

Li, Xinxin ^{[1
]}

机构：

[1] Chinese Acad Sci, State Key Lab Transducer Technol, Shanghai Inst Microsyst & Informat Technol, Shanghai 200050, Peoples R China

来源：

MICROELECTRONIC ENGINEERING | 2010年 / 87卷 / 11期

关键词：

Quad-cantilever; Low-cost single-sided micro-machining; Self-assembled sensing layer; Trace TNT detection; SENSOR;

D O I：

10.1016/j.mee.2010.03.010

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

This paper presents a quad-cantilever microsensor for on-the-spot detection of ultra-low concentration chemical vapors. Compared with conventional dual-cantilever sensors, the quad-cantilever configuration can form a fully cantilever-formed Wheatstone-bridge that possesses a higher sensitivity of twofold and more balanced condition to compensate for environmental noise like temperature fluctuation or air flow. Besides, the four integrated micro-cantilevers are made of SiO2, with each having a single crystal silicon piezoresistor fully encapsulated by SiO2. Thus, the quad-lever sensor achieves a very low signal noise of 0.2 mu V. For specific detection, sensitive molecule layer is self-assembled on two sensing cantilevers, with another two as reference. The sensors are micro-fabricated with a single-side process from the wafer front-side. With wet anisotropic etch used to release the piezoresistive cantilevers, the new fabrication technique features low-cost and high-yield. Self-assembled with a novel dual-branch specific monolayer, about 100 ppt level trinitrotoluene (TNT) vapor has been rapidly and repeatedly detected. (C) 2010 Elsevier B.V. All rights reserved.

引用

页码：2317 / 2322

页数：6