Micro and Nanostructures最新文献

The relentless trend toward miniaturization has brought interconnects to the brink of communication bottlenecks, operating at or near their ampacity (current carrying capacity) limits. This degradation in performance necessitates novel technologies with increased ampacity. This study explores optical interconnect (OI) as a potential future technology, offering high-bandwidth communication and low latency. This study models and simulates OI, integrating recent optical device advancements with modest modulator and detector capacitance (50 fF). Performance metrics including signal delay, power dissipation, and power-delay-product (PDP) are compared across copper (Cu) and single-wall carbon nanotube bundle (SWCNT-B) interconnects at 22 nm and 14 nm technology nodes. Results consistently show OI, with an active voltage current feedback (AVCF) based regulated gain cascode (RGC) transimpedance amplifier (TIA) receiver, outperforms Cu and SWCNT-B interconnects at global lengths and beyond. For instance, at 1000 μm and 22 nm, OI exhibits 88.47 % and 62.15 % delay improvements over Cu and SWCNT-B, respectively. This trend persists at 14 nm, with OI showing 93.68 % and 84.29 % delay improvements, respectively. Additionally, OI surpasses Cu and SWCNT-B in power efficiency beyond a critical length. As interconnects extend to global scales and beyond, the differences in delay, power, and PDP between OI and electrical interconnect increases, highlighting OI's advantages for future VLSI IC applications.

This paper aims to present a novel method to mitigate the undesirable issues associated with short-channel-effects (SCEs) and the critical lattice temperature of a fully depleted silicon-on-insulator (FD-SOI) MOSFET in the nanoscale regime. The proposed approach is based on simultaneously merging the energy barrier and heat-sink engineering simultaneously. Hafnium oxide as a high-k dielectric inside the channel region around the drain region is embedded to redistribute the band energy resulting in the enhancement of the energy barrier. This reformation of the band profile reduces variations in the channel depletion charge volume percentage caused by the drain voltage, thereby mitigating short-channel effects (SCEs). In order to promote effective thermal conduction, a portion of the buried oxide is replaced by doped P-type silicon which acts as an effective heat-sink. The devices under the investigation have been simulated using SILVACO software, considering the comprehensive physical models. Drain-Induced Barrier Lowering (DIBL), leakage current, I_on to I_off ratio, subthreshold swing, hot carrier effect and lattice temperature as the essential parameters have been successfully improved for the proposed device in comparison to the conventional device.

In this study, the performance of armchair phosphorene nanoribbons (APNRs) tunnel field-effect transistors (TFETs) is compared to that of conventional Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) based on the self-consistent solution of the Poisson and Schrödinger equation within the non-equilibrium Green's Function formalism and a tight-binding Hamiltonian. As channel length decreases, undesirable consequences such as increased OFF-current and sub-threshold swing can affect MOSFETs' performance. The study thoroughly investigates various aspects of TFET performance, including the impact of channel length, gate length, and doping on parameters like ON-current, OFF-current, the ON-/OFF-current ratio, and sub-threshold swing. An important finding of this research relates to the influence of source and drain doping. We demonstrate that fine-tuning impurity levels directly affects phosphorene nanoribbon TFET (PTFET) performance. The article also investigates the impact of gate length on PTFET performance. New transistor configurations with different gate lengths are proposed in this research. The study shows that optimizing gate length can significantly reduce OFF-current. Furthermore, the combined impact of gate length and doping concentration on PTFET performance is investigated. Through the strategic extension of the gate length towards the drain side and precise adjustments in doping levels, notable improvements in subthreshold swings, ON-current, and the ON-/OFF-current ratio can be realized.

In this work, a first-principles method based on density functional theory was systematically employed to investigate the stability, electronic properties, lithium-ion migration rates, and capacity-voltage curves of the LiFe_x-1M_xP_yN_y-1O₄ (M = Co/Mn, NS/Si) system. The results indicate that the lattice constants of the LiFe_x-1M_xP_yN_y-1O₄ (M = Co/Mn, NS/Si) system show little variation, and the system exhibits low formation and binding energies. Among the investigated systems, LFP-Mn/S demonstrates the best structural and thermodynamic stability. The bandgap of the doped systems decreases, leading to enhanced electronic conductivity. The LiFe_0.875Co_0.125P_0.875Si_0.125O₄ and LiFe_0.875Mn_0.125P_0.875Si_0.125O₄ systems remain semiconductors, while the LiFe_0.875Co_0.125P_0.875S_0.125O₄ and LiFe_0.875Mn_0.125P_0.875S_0.125O₄ systems exhibit semi-metallic properties due to the introduction of sulfur. Differential charge density calculations reveal changes in the covalent bond strength of the doped systems, with the introduction of Si and S respectively increasing and decreasing the covalency of their bonds with surrounding oxygen atoms. Additionally, doping reduces the Li-ion diffusion energy barriers, with the LiFe_0.875Co_0.125P_0.875Si_0.125O₄ system exhibiting the lowest migration energy barrier. The Li-ion diffusion rate is four orders of magnitude faster than that of the intrinsic system. This is attributed to changes in the average lengths of Li–O, Co–O, and Fe–O bonds. Finally, doping also alters the de-lithiation voltage, with values ranging from 2.69 V to 3.65 V for the doped systems, and the LiFe_0.875Co_0.125P_0.875Si_0.125O₄ system shows the highest complete de-lithiation voltage of 3.65 V. The overall performance improvements of the doped system have significant implications for enhancing the performance of Li-ion batteries.

N-methyl pyrrolidone (NMP) is an organic compound that is mainly used in chemical synthesis, the manufacture of anesthetics and pesticides, and the production of electronic materials, especially in the preparation of electrodes for lithium-ion batteries. However, their high volatility and toxicity pose potential risks to health and the environment. Therefore, the development of rapid, highly sensitive and low-cost NMP gas sensors is urgent. In this paper, ZnO nanorods were in situ grown on ceramic tubes via hydrothermal method and subsequently annealed at different temperatures. The gas sensing performance of ZnO nanorods after annealing at different temperatures was investigated. The results show that the ZnO nanorods annealed at 400 °C have more oxygen vacancies and excellent selectivity to NMP at 210 °C, with a response value of up to 67.33–100 ppm NMP, a response time of 25 s, and a low recovery time as low as 8 s. The sensors have potential applications for rapid monitoring of NMP and environmental health protection, providing a simple and feasible method for NMP detection.

This study proposes a multispectral camouflage tunable multilayer film metamaterial (TMFM) with thermal management function based on genetic algorithm (GA), which is composed of ZnS/YbF₃/Ge/Ge₂Sb₂Te₅ (GST)/Au multilayer film. Through numerical analysis, we assess its efficacy in visible-infrared compatibility camouflage and radiative heat dissipation. Within the visible light band, different structural colors can be produced by adjusting the thickness of the ZnS film. The average emissivity within the 3–5 μm and 8–14 μm infrared bands is measured at 0.04 and 0.14, respectively. The low emissivity facilitates effective thermal management. Moreover, an average emissivity of 0.52 within the 5–8 μm range is instrumental in achieving efficient radiation heat dissipation. Laser stealth capability is further enhanced, with an emissivity reaching 0.70 at 10.6 μm. Therefore, this metamaterial structure has broad application prospects in both military and civilian industrial fields.

This study explores the potential of randomly mixed carbon nanotube bundle (RMCB) as a viable on-chip interconnect. Achieving high-quality carbon nanotubes (CNTs) with uniform diameters is challenging for the current framework of enhanced fabrication techniques. The Stoyan and Yaskov technique is employed to optimize CNT arrangement within a specified rectangular area. This method accounts for statistical variation in CNT diameters, offering a more realistic and fabrication-focused approach to designing CNT bundle interconnects. Eight such practical RMCB structures (RMCB-50 to RMCB-350) are selected using this technique, each characterized by distinct CNT counts and variable diameters. Comprehensive average crosstalk-delay and reliability assessments are conducted by comparing different CNT bundle interconnects with the best-optimized RMCB (O-RMCB) interconnect, placed on various dielectric substrates such as SiO₂, SiC, BN. The study unequivocally indicates that O-RMCB produces highly favorable results and stands as the most suitable future solution for VLSI circuits. Additionally, the thickness optimization of O-RMCB interconnect is explored, yielding in improvements in both performance and reliability compared to other well-known CNT bundled interconnects.

In order to improve the gas-sensing performance of ZnO, a novel peony shaped ZnO stacked with nanosheets were prepared using hydrothermal method, and the obtained ZnO was characterized and tested for gas sensitivity. The results showed that the particle distribution of the peony shaped ZnO was uniform, with a particle size of about 0.8 μm. The gas-sensing response test results show that the peony shaped ZnO has excellent selectivity to ethanol gas. When the concentration of ethanol gas is 100 ppm, the gas-sensing response of the peony shaped ZnO to ethanol gas reaches 17.4, and the response time and recovery time are 8 s and 12 s, respectively. Even at an ethanol gas concentration of 2 ppm, the gas-sensing response of the peony shaped ZnO to ethanol gas can reach 2.1. Compared to existing literature reports, the peony shaped ZnO prepared in this paper has better gas-sensing performance. This study will provide data support and theoretical reference for the development of high-performance gas sensors.

This work presents a novel three-channel Tree-FET optimized for superior DC and analog performance metrics. The device structure features nanosheets with a width (NS_WD) of 9 nm, a thickness (NS_TH) of 5 nm, and interbidge dimensions of 8 nm in height (IB_HT) and 5 nm in width (IB_WD). The Tree-FET demonstrates an exceptional on/off current ratio of 10⁷ through meticulous engineering, significantly outperforming conventional FET configurations. Our comprehensive study explores the effects of different spacer materials, including HfO₂, Al₂O₃, Si₃N₄, and SiO₂, across varied channel lengths. The superior dielectric properties of HfO₂ contribute to fine-tuning the device's characteristics, making it a standout choice for optimizing performance. Out of all HfO₂ has been found to perform exceptionally well, offering the best combination of electrostatic control and minimized leakage currents. Because the Tree-FET has better electrostatic integrity and can keep working well with different spacer materials and channel lengths, it has much potential as a flexible and valuable part for next-generation semiconductor devices. The promising DC and analog metrics achieved through this novel design pave the way for developing more compact, high-performance electronic components.

A dielectric modulated embedded gate gate-all-around fin field-effect transistor (EGGAA-FinFET) has been proposed for label-free detection applications of biomolecules in this article. The design expands the biomolecule capture area by establishing a cavity below the embedded gate. The performance of EGGAA-FinFET and FinFET biosensors is analyzed in a comprehensive comparison in terms of electrical performance, sensitivity and selectivity. Some important biosensing characteristics for EGGAA-FinFET (FinFET) have been calculated to be 0.43 V (0.32 V) for threshold voltage sensitivity, 2.22 × 10⁶ (8.32 × 10⁴) for current switching ratio sensitivity, and 0.75 (0.65) for subthreshold swing sensitivity. To determine the optimal structure of the biosensor, the effect of structural parameters on sensitivity is investigated. In addition, the effect of the filling factor on the biosensor is considered. The real-world performance of biosensors is assessed using the linearity parameter, showing that the EGGAA-FinFET biosensor has better noise resistance compared to the FinFET biosensor.