Electric stress-induced threshold voltage instability of multilayer MoS2 field effect transistors.
We investigated the gate bias stress effects of multilayered MoS2 field effect transistors (FETs) with a back-gated configuration. The electrical stability of the MoS2 FETs can be significantly influenced by the electrical stress type, relative sweep rate, and stress time in an ambient environment. Specifically, when a positive gate bias stress was applied to the MoS2 FET, the current of the device decreased and its threshold shifted in the positive gate bias direction. In contrast, with a negative gate bias stress, the current of the device increased and the threshold shifted in the negative gate bias direction. The gate bias stress effects were enhanced when a gate bias was applied for a longer time or when a slower sweep rate was used. These phenomena can be explained by the charge trapping due to the adsorption or desorption of oxygen and/or water on the MoS2 surface with a positive or negative gate bias, respectively, under an ambient environment. This study will be helpful in understanding the electrical-stress-induced instability of the MoS2-based electronic devices and will also give insight into the design of desirable devices for electronics applications.
Department of Physics and Astronomy, Seoul National University , Gwanak-ro, Gwanak-gu, Seoul 151-744, Korea.
Kyungjune
K
Cho
Woanseo
W
Park
Juhun
J
Park
Hyunhak
H
Jeong
Jingon
J
Jang
Tae-Young
TY
Kim
Woong-Ki
WK
Hong
Seunghun
S
Hong
Takhee
T
Lee