title: Influence of water vapor on the electronic property of MoS2field effect transistors.
abstract: The influence of water vapor on the electronic property of MoS2field effect transistors (FETs) is studied through controlled experiments. We fabricate supported and suspended FETs on the same piece of MoS2to figure out the role of SiO2substrate on the water sensing property of MoS2. The two kinds of devices show similar response to water vapor and to different treatments, such as pumping in the vacuum, annealing at 500 K and current annealing, indicating the substrate does not play an important role in the MoS2water sensor. Water adsorption is found to decrease the carrier mobility probably through introducing a scattering center on the surface of MoS2. The threshold voltage and subthreshold swing of the FETs do not change obviously after introducing water vapor, indicating there is no obvious doping and trap introducing effects. Long time pumping in a high vacuum and 500 K annealing show negligible effects on removing the water adsorption on the devices. Current annealing at high source-drain bias is found to be able to remove the water adsorption and set the FETs to their initial states. The mechanism is proposed to be through the hot carriers at high bias.
authors.affiliation: Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871, People's Republic of China. Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, People's Republic of China.
authors.forename: Jiapei
authors.initials: J
authors.lastname: Shu
authors.forename: Gongtao
authors.initials: G
authors.lastname: Wu
authors.forename: Song
authors.initials: S
authors.lastname: Gao
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Xianlong
authors.initials: X
authors.lastname: Wei
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen