Proceedings of the Nature Research Society, 2017, 1, 01008
Published Online: 27 October 2017 (Article)
Recent studies on single- and multilayer molybdenum disulfide (MoS2) devices have revealed their promising characteristics as novel semiconductor devices. Here, we report the effects of environmental gases on the hysteresis in the transfer characteristics and observation of an anomalously large hysteresis below 1K for back-gated multilayered MoS2 field-effect transistors. Comparisons between different gases (oxygen, nitrogen, air, and nitrogen with varying relative humidities) revealed that water molecules acting as charge-trapping (dominantly hole-trapping) centers are the main cause of hysteresis. While the hysteresis persisted even after pumping out the environmental gas for longer than 24 h at room temperature, it disappeared when the device was cooled to 240 K, suggesting a considerable increase in the time constant of the charge trapping/detrapping at these modestly low temperatures. Below 1 K, we observed for the first time an anomalously large hysteresis, which is not attributed to charge trapping. We hypothesize that this hysteresis results from the slow injection of electrons via quantum tunneling through the Schottky barrier at the contacts. The size of the hysteresis increased with increase in the scan rate of the gate voltage, which is consistent with the possibility of very slow injection of electrons.
Citation Information: Yoshihiro Shimazu, Hysteresis of Transfer Characteristics in Field-Effect Transistors with a Molybdenum Disulfide Channel, Proceedings of the Nature Research Society, 2017, 1, 01008. doi: 10.11605/j.pnrs.201701008
Received: 26 May 2017, Accepted: 23 August 2017, Published Online: 27 October 2017