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Since the discovery of graphene in 2004, which proved the existence of 2-D crystals in nature, layered materials also known as van der Waals solids have received extensive reexamination, especially in the single-layer and multilayer forms because of their van der Waals type structure and unique properties that not only benefit many existing electronic components but also enable novel device concepts and design architectures. Numerous research efforts have been invested in these materials, and enormous quantities of results have been generated during the past 14 years. This paper provides an overview of the key physics and technology issues along with the most promising nanoelectronic applications of these materials and also identifies the challenges in this rapidly evolving field.

Background and Purpose: The AMP‐activated protein kinase (AMPK) signalling pathway is a desirable target for various cardiovascular diseases (CVD), while the involvement of AMPK‐mediated specific downstream pathways and effective interventions in hyperlipidaemia‐induced endothelial dysfunction remain largely unknown. Herein, we aim to identify an effective AMPK activator and to explore its efficacy and mechanism against endothelial dysfunction. Experimental Approach: Molecular docking technique was adopted to screen for the potent AMPK activator among 11 most common rare ginsenosides. In vivo, poloxamer 407 (P407) was used to induce acute hyperlipidaemia in C57BL/6J mice. In vitro, palmitic acid (PA) was used to induce lipid toxicity in HAEC cells. Key Results: We discovered the strongest binding of ginsenoside Rh4 to AMPKα1 and confirmed the action of Rh4 on AMPK activation. Rh4 effectively attenuated hyperlipidaemia‐related endothelial injury and oxidative stress both in vivo and in vitro and restored cell viability, mitochondrial membrane potential and mitochondrial oxygen consumption rate in HAEC cells. Mechanistically, Rh4 bound to AMPKα1 and simultaneously up‐regulated AKT/eNOS‐mediated NO release, promoted PGC‐1α‐mediated mitochondrial biogenesis and inhibited P38 MAPK/NFκB‐mediated inflammatory responses in both P407‐treated mice and PA‐treated HAEC cells. The AMPK inhibitor Compound C treatment completely abrogated the regulation of Rh4 on the above pathways and weakened the lowering effect of Rh4 on endothelial impairment markers, suggesting that the beneficial effects of Rh4 are AMPK dependent. Conclusion and Implications: Rh4 may serve as a novel AMPK activator to protect against hyperlipidaemia‐induced endothelial dysfunction, providing new insights into the prevention and treatment of endothelial injury‐associated CVD. [ABSTRACT FROM AUTHOR]

Copper-based interconnects employed in a wide range of integrated circuit (IC) products are fast approaching a dead-end due to their increasing resistivity and diminishing current carrying capacity with scaling, which severely degrades both performance and reliability. Here we demonstrate chemical vapor deposition-synthesized and intercalation-doped multilayer-graphene-nanoribbons (ML-GNRs) with better performance (more than 20% improvement in estimated delay per unit length), 25%/72% energy efficiency improvement at local/global level, and superior reliability w.r.t. Cu for the first time, for dimensions (down to 20 nm width and thickness of 12 nm) suitable for IC interconnects. This is achieved through a combination of GNR interconnect design optimization, high-quality ML-GNR synthesis with precisely controlled number of layers, and effective FeCl3 intercalation doping. We also demonstrate that our intercalation doping is stable at room temperature and that the doped ML-GNRs exhibit a unique width-dependent doping effect due to increasingly efficient FeCl3 diffusion in scaled ML-GNRs, thereby indicating that our doped ML-GNRs will outperform Cu even for sub-20 nm widths. Finally, reliability assessment conducted under accelerated stress conditions (temperature and current density) established that highly scaled intercalated ML-GNRs can carry over 2 × 108 A/cm2 of current densities, whereas Cu interconnects suffer from immediate breakdown under the same stress conditions and thereby addresses the key criterion of current carrying capacity necessary for an alternative interconnect material. Our comprehensive demonstration of highly reliable intercalation-doped ML-GNRs paves the way for graphene as the next-generation interconnect material for a variety of semiconductor technologies and applications.

InGaN/GaN green micro‐light‐emitting diode (micro‐LED, μLED) arrays with varying device sizes down to 4 μm are fabricated and characterized. The size effects on current‐voltage and capacitance‐voltage characteristics are analyzed showing minimal sidewall effects only at low bias. The influence of pulse modulation frequency on luminance is also characterized and the effect of diode negative capacitance is discussed. Subsequently, a universal and comprehensive compact model for μLEDs are built based on these findings, which covers the capacitance frequency dispersion and size scaling effects. This work reveals the significance of frequency in the display driving strategy and provides design enablement for μLED micro‐display applications including augmented/mixed reality (AR/MR). [ABSTRACT FROM AUTHOR]

The preparation of single-crystalline SrNbO2N particles using the flux method, in which NbOxNy impurities are generated, remains challenging. Herein, Sr5Nb4O15 with a Sr : Nb molar ratio of 1.25 was used as the precursor and NaCl served as flux. The reduction of Nb(V) and formation of NbOxNy impurities during the molten salt assisted thermal ammonolysis process was suppressed by the excess SrO in the precursor. On the other hand, the excess SrO hindered the growth of SrNbO2N grains. The concentration of SrO was controlled by adjusting the precursor-to-flux molar ratio. Meanwhile, the NH3 contact mode of secondary flow or transition flow slowed down the loss of SrO caused by ammonia gas blow-off, and thus controlled the growth of SrNbO2N crystals and defect formation. Well-defined single-crystalline SrNbO2N submicron particles and micron particles were prepared thereby. SrNbO2N particles were assembled into photoanodes by the method of electron-conducting array insertion, and the influence of crystal grain size on the performance of SrNbO2N photoanodes was investigated. [ABSTRACT FROM AUTHOR]

In thin‐film transistors (TFTs), issues such as interface states may lead to unstable device performance and complex physical phenomena, such as frequency dispersion effects. This paper establishes a three‐terminal TFT compact model capable of replicating capacitance dispersion phenomena and directly applying to SPICE circuit simulations. The model decomposes the transistor's capacitance frequency response into the superposition of responses from different electronic states. The different electronic states are emulated by parallel branches, each composed of voltage‐dependent capacitance and resistance connected in series. The Powell algorithm is employed to achieve automatic parameter optimization. The model is generic for TFTs and successfully replicates capacitance dispersion phenomena in carbon nanotube (CNT) and indium‐gallium‐zinc‐oxide (IGZO) thin‐film transistors. This work provides insights to the circuit behavior of display driver circuits at high frequencies and improving circuit reliability. [ABSTRACT FROM AUTHOR]

The fast growth of information technology has been sustained by continuous scaling down of the silicon-based metal-oxide field-effect transistor. However, such technology faces two major challenges to further scaling. First, [...]

The lacustrine shale in the Da'anzhai member of Jurassic in the central Sichuan Basin is a key exploration target for shale oil and gas resources in China in the future. This paper presents a detailed study of shale rock types and component characteristics, shale pore types and structural characteristics, and shale pore evolution characteristics under thermal simulation conditions through experimental analyses such as rock thin section and field emission scanning electron microscopy (FE-SEM) observation, conventional physical property test, X-ray diffraction (XRD) analysis, TOC test, liquid nitrogen adsorption (LNA) test, and thermal simulation (pore) experiment. The results show that minerals in the Da'anzhai shale are mainly clay minerals, quartz, and calcite, with a small amount of feldspar, dolomite, and pyrite. In the shale oil reservoirs, there are dominantly inorganic pores (e.g. clay intergranular pores), and relatively few organic pores. The specific surface area ranges from 1.064 m2/g to 9.227 m2/g, with an average of 4.949 m2/g. The pore volume is 0.003–0.016 cm3/g, with an average of 0.010 cm3/g. Mesopores contribute the most to the total pore volume and total specific surface area. With the increase of thermal simulation temperature, the degree of shale thermal evolution increases, and the shale porosity increases, predominantly, owing to the contribution of organic pores. It is concluded that inorganic pores, especially clay intergranular pores, are the dominant pore type in the Da'anzhai shale oil reservoirs, and the evolution degree, burial time and depth of organic matter can obviously improve the organic pores. [ABSTRACT FROM AUTHOR]