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The two-dimensional (2D) semiconducting family of XSi 2 N 4 (X = Mo and W), an emergent class of air-stable monolayers, has recently gained attention due to its distinctive structural, mechanical, transport, and optical properties. However, the electrical contact between XSi 2 N 4 and metals remains a mystery. In this study, we inspect the electronic and transport properties, specifically the Schottky barrier height (SBH) and tunneling probability, of XSi 2 N 4 -based van der Waals contacts by means of first-principles calculations. Our findings reveal that the electrical contacts of XSi 2 N 4 with metals can serve as the foundation for nanoelectronic devices with ultralow SBHs. We further analyzed the tunneling probability of different metal contacts with XSi 2 N 4 . We found that the H-phase XSi 2 N 4 /metal contact shows superior tunneling probability compared to that of H́-based metal contacts. Our results suggest that heterostructures at interfaces can potentially enable efficient tunneling barrier modulation in metal contacts, particularly in the case of MoSi 2 N 4 /borophene compared to MoSi 2 N 4 /graphene and WSi 2 N 4 /graphene in transport-efficient electronic devices. Among the studied heterostructures, tunneling efficiency is highest at the H and H́-MoSi 2 N 4 /borophene interfaces, with barrier heights of 2.1 and 1.52 eV, respectively, and barrier widths of 1.04 and 0.8 Å. Furthermore, the tunneling probability for these interfaces was identified to be 21.3 and 36.4%, indicating a good efficiency of carrier injection. Thus, our study highlights the potential of MoSi 2 N 4 /borophene contact in designing power-efficient Ohmic devices.

We demonstrate a hybrid inverter-type nanodevice composed of a MoS2 nanoflake field-effect transistor (FET) and ZnO nanowire Schottky diode on one substrate, aiming at a one-dimensional (1D)-two-dimensional (2D) hybrid integrated electronic circuit with multifunctional capacities of low power consumption, high gain, and photodetection. In the present work, we used a nanotransfer printing method using polydimethylsiloxane for the fabrication of patterned bottom-gate MoS2 nanoflake FETs, so that they could be placed near the ZnO nanowire Schottky diodes that were initially fabricated. The ZnO nanowire Schottky diode and MoS2 FET worked respectively as load and driver for a logic inverter, which exhibits a high voltage gain of ∼50 at a supply voltage of 5 V and also shows a low power consumption of less than 50 nW. Moreover, our inverter effectively operates as a photoinverter, detecting visible photons, since MoS2 FETs appear very photosensitive, while the serially connected ZnO nanowire Schottky diode was blind to visible light. Our 1D-2D hybrid nanoinverter would be quite promising for both logic and photosensing applications due to its performance and simple device configuration as well.