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Two-dimensional (2D) materials such as MoS2 have high potential for nanoelectronics because of their nanometer thickness and unique electrical properties. In this study, high-performance nanoscale channel MoS2 vertical field-effect transistors (VFETs) are fabricated using a simplified scaling method compatible with current micro/nanofabrication technologies. The obtained MoS2 VFET with 10 nm channel length (L) delivers a high current up to 537 μA/μm and an on–off ratio over 3 × 107 at room temperature. Meanwhile, a detailed study of the low-frequency noise (LFN) characteristic is carried out for the fabricated nanoscale MoS2 VFETs. The result shows that all of the MoS2 VFETs fit the classical 1/f noise model in the frequency range from 1 to 105 Hz and follows the carrier number fluctuation theory. The LFN of MoS2 VFETs also fits well with the 1/L relationship in the nanoscale channel conditions, which indicates the LFN is mainly generated in the channel region. As LFN performance may strongly depend on the characteristic size of the device, the relationships of normalized noise level with device area and volumetric oxide trap density with 1/L are evaluated. The fabrication strategy presented here provides a way to achieve high-performance 2D nanoscale devices with simplified fabrication processes and also lays the foundation for the study of LFN in nanoelectronics. [ABSTRACT FROM AUTHOR]

The integration of data storage and computing capabilities into a single physical component has led to the development of a microneuronal network system with high precision and speed rates. To achieve this system architecture, bold innovations in the underlying hardware structure and neural network architecture are required. This article introduces an optoelectronic storage device based on the MoS2/h-BN/graphene van der Waals heterojunction transistor. At room temperature, the transistor exhibits an electron mobility of up to 340 cm2/(V·s) and a large storage window due to its unique van der Waals heterojunction. The transistor's reconfigurable nonvolatile optoelectronic properties enable the construction of logic gates, including "AND", "OR", "NAND", and "NOR". Leveraging these logic gates, a microneural network system is created that simulates future machine vision applications. The system achieves a remarkable recognition rate of 96.3% for images in a multidimensional color space, demonstrating the significant development potential of the microneural network system based on the MoS2/h-BN/graphene vdW heterojunction transistor in future machine vision. [ABSTRACT FROM AUTHOR]

Atomically thin monolayer two-dimensional (2D) semiconductors with natural immunity to short channel effects are promising candidates for sub-10 nm very large-scale integration technologies. Herein, the ultimate limit in optoelectronic performances of monolayer WSe 2 field-effect transistors (FETs) is examined by constructing a sloping channel down to 6 nm. Using a simple scaling method compatible with current micro/nanofabrication technologies, we achieve a record high saturation current up to 1.3 mA/μm at room temperature, surpassing any reported monolayer 2D semiconductor transistors. Meanwhile, quasi-ballistic transport in WSe 2 FETs is first demonstrated; the extracted high saturation velocity of 4.2 × 10 6 cm/s makes it suitable for extremely sensitive photodetectors. Furthermore, the photoresponse speed can be improved by reducing channel length due to an electric field-assisted detrapping process of photogenerated carriers in localized states. As a result, the sloping-channel device exhibits a faster response, higher detectivity, and additional polarization resolution ability compared to planar micrometer-scale devices.