title: Highly enhanced gas sensing in single-walled carbon nanotube-based thin-film transistor sensors by ultraviolet light irradiation.
abstract: Single-walled carbon nanotube (SWCNT) random networks are easily fabricated on a wafer scale, which provides an attractive path to large-scale SWCNT-based thin-film transistor (TFT) manufacturing. However, the mixture of semiconducting SWCNTs and metallic SWCNTs (m-SWCNTs) in the networks significantly limits the TFT performance due to the m-SWCNTs dominating the charge transport. In this paper, we have achieved a uniform and high-density SWCNT network throughout a complete 3-in. Si/SiO2 wafer using a solution-based assembly method. We further utilized UV radiation to etch m-SWCNTs from the networks, and a remarkable increase in the channel current on/off ratio (Ion/Ioff) from 11 to 5.6 × 103 was observed. Furthermore, we used the SWCNT-TFTs as gas sensors to detect methyl methylphosphonate, a stimulant of benchmark threats. It was found that the SWCNT-TFT sensors treated with UV radiation show a much higher sensitivity and faster response to the analytes than those without treatment with UV radiation.
authors.affiliation: Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China. lmwei@sjtu.edu.cn.
authors.forename: Tingting
authors.initials: T
authors.lastname: Chen
authors.forename: Liangming
authors.initials: L
authors.lastname: Wei
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Zhou
authors.forename: Diwen
authors.initials: D
authors.lastname: Shi
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhao
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yu
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Yafei
authors.initials: Y
authors.lastname: Zhang