Electrical and optical characterization of MoS2 thin film transistors and the effect of strain on their performances

Two-dimensional transition-metal dichalcogenides (TMDCs) such as MoS2 are potential channel materials for thin film transistor. Here, we report the effects of strain on the performance of the back-gated few-layer MoS2 thin film transistors (FL-MoS2 TFTs) with poly(acrylic acid) (PAA) dielectric layer. The devices exhibit high on/off ratio of 5600 and mobility of 7.07 cm/Vs. The electrical and optical characterizations were affected by the strain under bending conditions. The results show that the device exhibits quite stable mobility and photoswitching behavior under different bending radius, which is owing to the high deformability of MoS2 and PAA dielectric layer. Big bending radius enable improved photoresponsitivity due to the change of band gap of MoS2. The excellent bending performance of FL-MoS2 transistor presents potential applications in flexible and wearable electronics and optoelectronics.