Flexible nano-hybrid inverter based on inkjet-printed organic and 2D multilayer MoS2 thin film transistor

We report a novel platform on which we design a flexible high-performance complementary metal–oxide–semiconductor (CMOS) inverter based on an inkjet-printed polymer PMOS and a two-dimensional (2D) multilayer molybdenum disulfide (MoS₂) NMOS on a flexible substrate. The initial implementation of a hybrid complementary inverter, comprised of 2D MoS₂ NMOS and polymer PMOS on a flexible substrate, demonstrates a compelling new pathway to practical logic gates for digital circuits, achieving extremely low power consumption with low sub-1 nA leakage currents, high performance with a voltage gain of 35 at 12 V supply voltage, and high noise margin (larger than 3 V at 12 V supply voltage) with low processing costs. These results suggest that inkjet-printed organic thin film transistors and 2D multilayer semiconducting transistors may form the basis for potential future high performance and large area flexible integrated circuitry applications.     

Human postural control against external force perturbation applied to the high-back

Many studies have reported postural control against support surface translation. However, postural control mechanism against external force perturbation is not clear. Therefore, in this study we investigated the postural recovery against external force (1∼4Kg) applied to the high-back in health young male subjects (24±4 years). Kinematic data and center of pressure of the reaction to an unexpected perturbation were analyzed. Experimental results showed that the hill-lifting strategy with ankle plantarflexion and knee hyperextension was used in all subjects, regardless of the force magnitude. Specifically, maximum ankle plantarflexion and hip flexion increased with the perturbation force magnitude, the heel vertical excursion and anterior COP excursion. The results of this study show that the postural control strategy for the external force perturbation is quite different from that for surface translation and needs further investigation.     

A highly sensitive chemical gas detecting transistor based on highly crystalline CVD-grown MoSe<Subscript>2</Subscript> films

Layered semiconductors with atomic thicknesses are becoming increasingly important as active elements in high-performance electronic devices owing to their high carrier mobilities,large surface-to-volume ratios,and rapid electrical responses to their surrounding environments.Here,we report the first implementation of a highly sensitive chemical-vapor-deposition-grown multilayer MoSe2 field-effect transistor (FET) in a NO2 gas sensor.This sensor exhibited ultra-high sensitivity (S =ca.1,907 for NO2 at 300 ppm),real-time response,and rapid on-off switching.The high sensitivity of our MoSe2 gas sensor is attributed to changes in the gap states near the valence band induced by the NO2 gas absorbed in the MoSe2,which leads to a significant increase in hole current in the off-state regime.Device modeling and quantum transport simulations revealed that the variation of gap states with NO2 concentration is the key mechanism in a MoSe2 FET-based NO2 gas sensor.This comprehensive study,which addresses material growth,device fabrication,characterization,and device simulations,not only indicates the utility of MoSe2 FETs for high-performance chemical sensors,but also establishes a fundamental understanding of how surface chemistry influences carrier transport in layered semiconductor devices.