Electronic properties and transistors of the NbS-MoS-NbS NR heterostructure.

Based on density function theory and nonequilibrium Green's functions, we construct a NbS-MoS-NbS NR inplane heterostructure. The effects of channel length, width, chirality and vacancy of the heterostructure on transport properties are systematically investigated. The electron transport of the armchair-edge heterostructure device shows ballistic transport properties, while the zigzag-edge heterostructure device exhibits resonance tunneling transport properties. Further study indicates NbS-MoS-NbS field effect transistors (FETs) to be excellent ambipolar transistors. The FETs have high performances with current on/off ratio 4.7 × 10 and subthreshold swing 90 mV/decade with channel length m = 16 and width n = 6.  Increases in the channel length sharply reduce the off-state current and enhance the performance of the devices significantly.