Fabrication and sensing properties of a micro-humidity sensor system using CMOS technology

• Published in: Electronic materials letters Vol. 6; no. 1; pp. 7 - 12
• Main Author: Lee, Sung Pil
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.03.2010; 대한금속·재료학회
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed Matter Physics; Materials Science; Nanotechnology; Nanotechnology and Microengineering; Optical and Electronic Materials; 전자/정보통신공학; micro humidity sensor; CMOS; OP amp; carbon nitride
• ISSN: 1738-8090; 2093-6788
• DOI: 10.3365/eml.2010.03.007

A micro-humidity sensor system is designed and fabricated by 0.8 μm analog mixed CMOS technology. The integrated sensor system consists of an n-channel differential FET humidity sensor, a Wheatstone bridge humidity senor, and an operational amplifier block, respectively. The differential sensor employs carbon nitride films as a new sensing material and has a pair of transistors, a sensing transistor and a non-sensing transistor (reference transistor), to eliminate unexpected effects. The drain current of the FET humidity sensor increases from 0.88 mA to 0.99 mA as the relative humidity increases from 10 %RH to 70 %RH.