Integrating Metal-Oxide-Decorated CNT Networks with a CMOS Readout in a Gas Sensor

Sensors

Hyunjoong Lee²  Sanghoon Lee²  Dai-Hong Kim³  David Perello¹  Young June Park²  Seong-Hyeon Hong³  Minhee Yun¹ 

[1] Department of Electrical and Computer Engineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA; E-Mails:;Department of Electrical Engineering, Seoul National University, Seoul, 151-744, Korea; E-Mails:;Department of Materials Science and Engineering and Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744, Korea; E-Mails:

关键词: carbon nanotube (CNT);    read-out integrated circuit;    single die;    metal decoration;   

DOI  :  10.3390/s120302582

来源: mdpi

【 摘 要 】

We have implemented a tin-oxide-decorated carbon nanotube (CNT) network gas sensor system on a single die. We have also demonstrated the deposition of metallic tin on the CNT network, its subsequent oxidation in air, and the improvement of the lifetime of the sensors. The fabricated array of CNT sensors contains 128 sensor cells for added redundancy and increased accuracy. The read-out integrated circuit (ROIC) was combined with coarse and fine time-to-digital converters to extend its resolution in a power-efficient way. The ROIC is fabricated using a 0.35 μm CMOS process, and the whole sensor system consumes 30 mA at 5 V. The sensor system was successfully tested in the detection of ammonia gas at elevated temperatures.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland