Moon S E, Lee H K, Choi N J, Lee J, Yang W S, Kim J, Jong J J, Yoo D J
Convergence Components and Materials Research Laboratory, Electronics and Telecommunications Research Institute, Daejeon 305-700, Korea.
J Nanosci Nanotechnol. 2012 Jul;12(7):5543-6. doi: 10.1166/jnn.2012.6364.
An NO2 micro gas sensor was fabricated based on a micro-heater using tin oxide nano-powders for effective gas detection and monitoring system with low power consumption and high sensitivity. The processes of the fabrication were acceptable to the conventional CMOS processes for mass-production. Semiconducting SnO2 nano-powders were synthesized via the co-precipitation method; and to increase the sensitivity of the NO2 gas rare metal dopants were added. In the structure of the micro-heater, the resistances of two semi-circular Pt heaters were connected to the spreader for thermal uniformity. The resistance of each heater becomes an electrically equal Wheatstone-bridge, which was divided in half by the heat spreading structure. Based on the aforementioned design, a low-power-consumption micro-heater was fabricated using the CMOS-compatible MEMS processes. A bridge-type micro-heater based on the Si substrate was fabricated via surface micro-machining. The NO2 sensing properties of a screen-printed tin oxide thick film device were measured The micro gas sensors showed substantial sensitivity down to 0.5 ppm NO2 at a low power consumption (34.2 mW).
基于微加热器并使用氧化锡纳米粉末制备了一种二氧化氮微气体传感器，用于构建具有低功耗和高灵敏度的高效气体检测与监测系统。该制造工艺适用于传统的CMOS工艺以进行大规模生产。通过共沉淀法合成了半导体氧化锡纳米粉末；为提高对二氧化氮气体的灵敏度，添加了稀有金属掺杂剂。在微加热器结构中，两个半圆形铂加热器的电阻连接到用于热均匀性的散热器。每个加热器的电阻构成一个电平衡的惠斯通电桥，该电桥被热扩散结构一分为二。基于上述设计，采用与CMOS兼容的MEMS工艺制造了一种低功耗微加热器。通过表面微加工制造了基于硅衬底的桥式微加热器。测量了丝网印刷氧化锡厚膜器件的二氧化氮传感特性。该微气体传感器在低功耗（34.2毫瓦）下对低至0.5 ppm的二氧化氮显示出显著的灵敏度。
