Open AccessIntegrated microoxygen sensor based on nanostructured TiO 2 thin films
Author(s) -
Wang Hairong,
Wang Jiaxin,
Chen Lei,
Yao Yuqing,
Sun Quantao,
Qunming Zhang
Publication year - 2015
Publication title -
micro and nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.25
H-Index - 31
ISSN - 1750-0443
DOI - 10.1049/mnl.2015.0111
Subject(s) - microheater , materials science , optoelectronics , substrate (aquarium) , electrode , layer (electronics) , etching (microfabrication) , thin film , microelectromechanical systems , silicon , sensitivity (control systems) , hysteresis , nanotechnology , response time , electronic engineering , fabrication , computer science , medicine , oceanography , alternative medicine , chemistry , physics , pathology , quantum mechanics , computer graphics (images) , engineering , geology
An integrated microoxygen sensor based on the nanostructured TiO 2 thin film is presented. A pair of interdigitated electrodes was designed with the microheater around them on the same layer, which was aimed at simplifying the structure and avoiding fracture of the embedded heater. To fabricate the sensor chips, an optimisation process consisting of 14 steps was designed. The adiabatic cavity was formed by releasing the Si substrate from backside to a certain thickness at first, then a TiO 2 film was prepared by the sol–gel process and patterned by the wet etching process, after that electrodes and the heater were patterned and finally the remaining silicon was thinned further. Response properties to different gases were tested, and the sensor shows a good sensitivity of 0.093 and high selectivity of 0.258 to O 2 than H 2 , response time of 51 s and hysteresis of 2.93%. The integrated microoxygen sensor has potential applications on the occasions of miniaturised, integrated, low power and mass production.