Publications by authors named "Junchuan Tang"

Innovations in device architectures and materials promote transistor miniaturization for improved performance, energy efficiency and integration density. At foreseeable ångström nodes, a gate-all-around (GAA) field-effect transistor based on two-dimensional (2D) semiconductors would provide excellent electrostatic gate controllability to achieve ultimate power scaling and performance delivering. However, a major roadblock lies in the scalable integration of 2D GAA heterostructures with atomically smooth and conformal interfaces.

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Hexagonal boron nitride (hBN) has emerged as a promising protection layer for dielectric integration in the next-generation large-scale integrated electronics. Although numerous efforts have been devoted to growing single-crystal hBN film, wafer-scale ultraflat hBN has still not been achieved. Here, we report the epitaxial growth of 4 in.

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Vertical semiconducting fins integrated with high-κ oxide dielectrics have been at the centre of the key device architecture that has promoted advanced transistor scaling during the last decades. Single-fin channels based on two-dimensional (2D) semiconductors are expected to offer unique advantages in achieving sub-1 nm fin-width and atomically flat interfaces, resulting in superior performance and potentially high-density integration. However, multi-fin structures integrated with high-κ dielectrics are commonly required to achieve higher electrical performance and integration density.

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With the development of cryo-electron microscopy (cryo-EM), high-resolution structures of macromolecules can be reconstructed by the single particle method efficiently. However, challenges may still persist during the specimen preparation stage. Specifically, proteins tend to adsorb at the air-water interface and exhibit a preferred orientation in vitreous ice.

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Precise integration of two-dimensional (2D) semiconductors and high-dielectric-constant (k) gate oxides into three-dimensional (3D) vertical-architecture arrays holds promise for developing ultrascaled transistors, but has proved challenging. Here we report the epitaxial synthesis of vertically aligned arrays of 2D fin-oxide heterostructures, a new class of 3D architecture in which high-mobility 2D semiconductor fin BiOSe and single-crystal high-k gate oxide BiSeO are epitaxially integrated. These 2D fin-oxide epitaxial heterostructures have atomically flat interfaces and ultrathin fin thickness down to one unit cell (1.

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The integration of large-scale two-dimensional (2D) materials onto semiconductor wafers is highly desirable for advanced electronic devices, but challenges such as transfer-related crack, contamination, wrinkle and doping remain. Here, we developed a generic method by gradient surface energy modulation, leading to a reliable adhesion and release of graphene onto target wafers. The as-obtained wafer-scale graphene exhibited a damage-free, clean, and ultra-flat surface with negligible doping, resulting in uniform sheet resistance with only ~6% deviation.

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High-mobility and air-stable two-dimensional (2D) BiOSe semiconductor holds promise as an alternative fast channel material for next-generation transistors. However, one of the key challenges remaining in 2D BiOSe is to prepare high-quality crystals to fabricate the high-performance transistors with a high on-state current density. Here, we present the free-standing growth of strain-free 2D BiOSe crystals.

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The development of highly active and multifunctional carbocatalysts modified with heteroatoms or metal species is crucial for practical environmental remediation applications. In this study, nitrogen-doped porous carbon embedded with highly dispersed CoO nanodots (CoO-N-C) was successfully prepared from a biomass-derived Schiff base polymer for the first time. The morphology analysis shows that CoO nanodots were embedded in the N doped carbon layer with size of ∼6.

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