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Assembling two-dimensional (2D) crystals via weak van der Waals (vdW) interactions in a vertical stack reveals various exciting physical phenomena and becomes essential for high-performance electronic devices through band alignment modulation. These vdW heterostructures enable the creation of primary electronic components, such as diodes and transistors, facilitating multifunctional device integration on a single chip and offering significant potential for analog and digital electronics. This study demonstrates the potential of metal–insulator–semiconductor (MIS) diodes within 2D vdW heterostructures, focusing on a combination of black phosphorus (BP), thin hexagonal boron nitride (hBN), and graphene (Gr). The BP/hBN/Gr MIS diode is fabricated using a dry transfer method to vertically stack the layered materials. Comparative analysis with similar metal–semiconductor diodes reveals superior current rectification in the MIS diode, attributed to carrier tunneling at the interfaces. We evaluate the performance metrics, including the rectification ratio, ideality factor, and tunneling behavior, over a temperature range of 77–300 K. The device exhibits a rectification ratio of 3.5 × 102 and an ideality factor of 1.6. Our findings highlight the potential of MIS diodes in ultrathin nanoelectronics, offering insights for future advancements in electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The exponential development in quantum phenomena is directly correlated with the decreasing size of nano‐semiconductor transistors. Consequently, the use of a quantum structure that deviates from traditional transistor types becomes imperative. Electrostatically defined nanoscale devices within 2D semiconductor heterostructures serve as foundational elements for diverse quantum electrical circuits. Van der Waals heterostructures, distinguished by atomically flat interfaces and inherent 2D characteristics, offer advantages such as large‐scale uniformity, flexibility, and portability over conventional bulk semiconductor heterostructures. Herein, the intricate electronic behavior of a MoS2/WSe2 encapsulated heterostructure governed by split‐gate and middle‐gate configurations is investigated, revealing a distinctive step‐like current profile at a low temperature of 77 K. The observed four regimes in the current highlight the impact of quantum confinement induced by reduced lateral dimensions, coupled with precise electrostatic confinement controlled by gate voltages. The temperature dependence of the phenomena emphasizes the role of thermal effects on carrier scattering mechanisms. In addition, the pinch‐off characteristics with different temperatures, middle‐gate voltages, and drain biases are explored. This study contributes to a deeper understanding of electrostatic effects in 2D transition metal dichalcogenide heterostructures and holds promise for the development of advanced electronic devices with tailored confinement for enhanced functionalities. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) atomic crystalline transition metal dichalcogenides has shown immense features, aiming for future nanoelectronic devices comparable to conventional silicon (Si). 2D molybdenum ditelluride (MoTe2) has a small bandgap, appears close to that of Si, and is more favorable than other typical 2D semiconductors. In this study, we demonstrate laser-induced p-type doping in a selective region of n-type semiconducting MoTe2 field effect transistors (FET) with an advance in using the hexagonal boron nitride as passivation layer from protecting the structure phase change from laser doping. A single nanoflake MoTe2-based FET, exhibiting initial n-type and converting to p-type in clear four-step doping, changing charge transport behavior in a selective surface region by laser doping. The device shows high electron mobility of about 23.4 cm2V−1s−1 in an intrinsic n-type channel and hole mobility of about 0.61 cm2V−1s−1 with a high on/off ratio. The device was measured in the range of temperature 77–300 K to observe the consistency of the MoTe2-based FET in intrinsic and laser-dopped region. In addition, we measured the device as a complementary metal–oxide–semiconductor (CMOS) inverter by switching the charge-carrier polarity of the MoTe2 FET. This fabrication process of selective laser doping can potentially be used for larger-scale MoTe2 CMOS circuit applications. [ABSTRACT FROM AUTHOR]