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Van der Waals heterostructures (vdWHs) have attracted tremendous interest owing to the ability to assemble diverse building blocks without the constraints of lattice matching and processing compatibility. However, once assembled, the fabricated vdWHs can hardly be separated into individual building blocks for further manipulation, mainly due to technical difficulties in the disassembling process. Here, we show a method to disassemble the as-fabricated vdWHs into individual building blocks, which can be further reassembled into new vdWHs with different device functionalities. With this technique, we demonstrate reconfigurable transistors from n-type to p-type and back-gate to dual-gate structures through re-stacking. Furthermore, reconfigurable device behaviors from floating gate memory to Schottky diode and reconfigurable anisotropic Raman behaviors have been obtained through layer re-sequencing and re-twisting, respectively. Our results could lead to a reverse engineering concept of disassembled vdWHs electronics in parallel with state-of-the-art vdWHs electronics, offering a general method for multi-functional pluggable electronics and optoelectronics with limited material building blocks.

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Abstract2D Semiconductors are promising in the development of next‐generation photodetectors. However, the performances of 2D photodetectors are largely limited by their poor light absorption (due to ultrathin thickness) and small detection range (due to large bandgap). To overcome the limitations, a strain‐plasmonic coupled 2D photodetector is designed by mechanically integrating monolayer MoS2 on top of prefabricated Au nanoparticle arrays. Within this structure, the large biaxial tensile strain can greatly reduce the MoS2 bandgap for broadband photodetection, and at the same time, the nanoparticles can significantly enhance the light intensity around MoS2 with much improved light absorption. Together, the strain‐plasmonic coupled photodetector can broaden the detection range by 60 nm and increase the signal‐to‐noise ratio by 650%, representing the ultimate optimization of detection range and detection intensity at the same time. The strain‐plasmonic coupling effect is further systematically characterized and confirmed by using Raman and photoluminescence spectrophotometry. Furthermore, the existence of built‐in potential and photo‐switching behavior is demonstrated between the strained and unstrained region, constructing a self‐powered homojunction photodetector. This approach provides a simple strategy to couple strain effect and plasmonic effect, which can provide a new strategy for designing high‐performance and broadband 2D optoelectronic devices.

Two-dimensional (2D) semiconductors have attracted considerable attention in recent years. However, to date, there is still no effective approach to produce large-scale monolayers while retaining their intrinsic properties. Here, we report a simple mechanical exfoliation method to produce large-scale and high-quality 2D semiconductors, by designing an atomically flat Au-mesh film as the peeling tape. Using our prefabricated mesh tape, the limited contact region (between the 2D crystal and Au) could provide enough adhesion to mechanically exfoliate uniform 2D monolayers, and the noncontact region (between the mesh holes and monolayers) ensures weak interaction to mechanically release the 2D monolayers on desired substrates. Together, we demonstrate a scalable method to dry exfoliate various 2D monolayer arrays onto different substrates without involving any solutions or contaminations, representing the optimization between material yield, scalability, and quality. Furthermore, detailed optical and electrical characterizations are conducted to confirm their intrinsic quality. With the ability to mechanically exfoliate various 2D arrays and further restacking them, we have demonstrated large-scale van der Waals heterostructure arrays through layer-to-layer assembling. Our study offers a simple and scalable method for dry exfoliating 2D monolayer and heterostructure arrays with intrinsic material quality, which could be crucial to accelerate fundamental investigations as well as practical applications of proof-of-concepts devices.