Abstract
The IC industry in the Chinese mainland has encountered the difficulty caused by the embargo on lithography machines in developing state-of-the-art semiconductor IC processes. For the first ...time, this work fabricates out the HVTFET which we have independent intellectual property rights. A 50 nm channel length N HVTFET device is fabricated successfully using a 0.35 µm process, and its characteristics are close to those of TSMC’s 55 nm planar N MOSFET. The experimental results of this paper have two important significances. First, it shows that the fabrication of the advanced ICs in the Chinese mainland can get rid of the limitation of the lithography machine by using the HVTFET. Second, it shows that it is possible to decrease the chip area by about 3/4 by using the HVTFET structure for the ICs with 28 nm and above planar MOS processes, which are quite common in China.
Abstract With the continuous exploration of researchers in the field of sodium-ion batteries, the performance of sodium-ion batteries has been greatly improved, and it has a wide range of application ...prospects in large-scale energy storage, traffic power and other fields. Hard carbon is the most important anode material for sodium-ion batteries. Although it has the advantages of low cost, stable structure and performance, it still has the problems of low initial coulomb efficiency (ICE) and poor rate performance in application. In order to solve the problem of low ICE of hard carbon anode of sodium-ion battery, literatures about hard carbon anode of sodium-ion battery in recent years are comprehensively reviewed. Based on the microstructure of hard carbon material, the causes of low ICE of hard carbon are analyzed. At the same time, from the point of view of material structure design and regulation, the current optimization strategies of hard carbon anode ICE are summarized, including the following aspects: optimization and improvement of carbonization process, precursor screening and design, surface coating strategy, micro-pore structure control and catalytic carbonization strategy. It is hoped that this review can provide reference for further optimization of hard carbon properties and its large-scale application in sodium-ion batteries.
With the increasing demands of X‐ray detection and medical diagnosis, organic scintillators with intense and tunable X‐ray excited emission have been becoming important. To guarantee the X‐ray ...absorption, heavy atoms were widely added in reported organic scintillators, which led to emission quenching. In this work, we propose a new strategy to realize organic scintillators through the host‐guest doping strategy. Then the X‐ray absorption centers (host) and emission centers (guest) are separated. Under X‐ray excitation, these materials displayed intense and readily tunable emissions ranging from green (520 nm) to near infrared (NIR) regions (682 nm). Besides, the relationship between the X‐ray absorption and spatial arrangement of the heavy atoms in the host matrix was also revealed. The potential application of these wide‐range color tunable organic host‐guest scintillators in X‐ray imaging were demonstrated. This work provides a new feasible strategy for constructing high‐performance organic scintillators with tunable luminescence properties.
A new strategy to achieve organic scintillators through constructing host‐guest doping system was demonstrated. When doping guest materials with different triplet state energy levels, readily tunable emissions ranging from green (520 nm) to near infrared (NIR) regions (682 nm) were achieved under X‐ray excitation. The developed system also enabled color‐tunable NIR X‐ray imaging and provided a convenient visualization tool for X‐ray radiography.
Abstract
Research on strengthening and retrofitting of concrete structures against explosive loading has recently received much attention. This paper proposes a new type of reinforcement for concrete ...panels to enhance their blast‐resistant capacity. The reinforcement structure is naturally optimized with continuous nonself‐intersecting surfaces, known as triply periodic minimal surface (TPMS)‐primitive scaffold. A numerical model is developed to investigate the performance of TPMS‐primitive reinforced concrete panels against blast loading. The results are validated by experimental data from the literature on a traditional reinforced concrete slab. The concrete slabs reinforced with one, two, and four layers of TPMS‐primitive unit cells are designed and examined, while a quarter of the panel is simulated to reduce the computational cost. A constitutive model that considers the strain‐rate effect is employed to capture the rate‐dependent impulsive behavior of the proposed panels. The numerical results indicate significant enhancements in damage resistance and substantial reductions in deflection of the concrete reinforced panels when the TPMS‐primitive scaffold replaces the rebar lattice. The proposed reinforcement with multiple layers of unit cells retains high efficiency through parametric studies, while changes in the shell thickness of the reinforcement scaffold have limited effects on filtering blast waves.
The ability to incorporate functional metal ions (Mn+) into metal–organic coordination complexes adds remarkable flexibility in the synthesis of multifunctional organic–inorganic hybrid materials ...with tailorable electronic, optical, and magnetic properties. We report the cation‐exchanged synthesis of a diverse range of hollow Mn+‐phytate (PA) micropolyhedra via the use of hollow Co2+‐PA polyhedral networks as templates at room temperature. The attributes of the incoming Mn+, namely Lewis acidity and ionic radius, control the exchange of the parent Co2+ ions and the degree of morphological deformation of the resulting hollow micropolyhedra. New functions can be obtained for both completely and partially exchanged products, as supported by the observation of Ln3+ (Ln3+=Tb3+, Eu3+, and Sm3+) luminescence from as‐prepared hollow Ln3+‐PA micropolyhedra after surface modification with dipicolinic acid as an antenna. Moreover, Fe3+‐ and Mn2+‐PA polyhedral complexes were employed as magnetic contrast agents.
The cation exchanged synthesis of diverse hollow metal‐phytate (PA) polyhedral complexes is reported using hollow Co2+‐PA micropolyhedra as templates in a liquid phase. The synthetic strategy enables facile addition of multiple functionalities within the metal‐PA polyhedral networks with simultaneous control of their physicochemical features under mild conditions.
In this paper, a Hetero-junction Vertical Trench MOSFET (HVTFET) is proposed. The HVTFET has a multilayer structure. Compared with FinFETs and GAAs, the HVTFET provides a new method to effectively ...overcome the DIBL effect of the small-size IC. The channel length L ch of HVTFET is determined by the thickness of the epitaxial channel region, so the L ch can be reduced greatly, therefore the operating frequency of the HVTFET can be greatly increased. The HVTFET can achieve higher V dd by increasing the length of the low-doped drain region or reducing its doping concentration. The 7nm HVTFET simulation model has been established by using Sentaurus TCAD and it can work normally. The HVTFET breaks though the traditional IC reduction rule, and the HVTFET will lead IC to move forward in the future.
In this paper, 45 GHz and 60 GHz power amplifiers（PAs） with high output power have been successfully designed by using 90 nm CMOS process. The 45 GHz（60 GHz） PA consists of two（four） differential ...stages. The sizes of transistors have been designed in an appropriate way so as to trade-off gain, efficiency and stability. Due to limited supply voltage and low breakdown voltage of CMOS MOSFET compared with the traditional III-V technologies, the technique of power combining has been applied to achieve a high output power. In particular, a novel 8-way distributed active transformer power combiner has been proposed for realizing such mm-wave PA. The proposed transformer combiner with a fully symmetrical layout can improve its input impedance balance at mm-wave frequency regime significantly. Taking its advantages of this novel transformer based power combiner, our realized 45 GHz（60 GHz） mm-wave PA has achieved the gain of20.3 d B（16.8 d B）, the maximum PAE of 14.5%（13.4%） and the saturated output power of 21 d Bm（21 d Bm）with the 1.2 V supply voltage.
Abstract
The heating and cooling energy consumption of buildings accounts for about 15% of national total energy consumption in the United States. In response to this challenge, many promising ...technologies with minimum carbon footprint have been proposed. However, most of the approaches are static and monofunctional, which can only reduce building energy consumption in certain conditions and climate zones. Here, we demonstrate a dual-mode device with electrostatically-controlled thermal contact conductance, which can achieve up to 71.6 W/m
2
of cooling power density and up to 643.4 W/m
2
of heating power density (over 93% of solar energy utilized) because of the suppression of thermal contact resistance and the engineering of surface morphology and optical property. Building energy simulation shows our dual-mode device, if widely deployed in the United States, can save 19.2% heating and cooling energy, which is 1.7 times higher than cooling-only and 2.2 times higher than heating-only approaches.
Integrating mobile edge computing (MEC) into the Internet of Things (IoT) enables the IoT devices of limited computation capabilities and energy to offload their computation-intensive and ...delay-sensitive tasks to the network edge, thereby providing high quality of service to the devices. In this article, we apply non-orthogonal multiple access (NOMA) technique to enable massive connectivity and investigate how it can be exploited to achieve energy-efficient MEC in IoT networks. In order to maximize the energy efficiency for offloading, while simultaneously satisfying the maximum tolerable delay constraints of IoT devices, a joint radio and computation resource allocation problem is formulated, which takes both intra- and inter-cell interference into consideration. To tackle this intractable mixed integer non-convex problem, we first decouple it into separated radio and computation resource allocation problems. Then, the radio resource allocation problem is further decomposed into a subchannel allocation problem and a power allocation problem, which can be solved by matching and sequential convex programming algorithms, respectively. Based on the obtained radio resource allocation solution, the computation resource allocation problem can be solved by utilizing the Knapsack method. Numerical results validate our analysis and show that our proposed scheme can significantly improve the energy efficiency of NOMA-enabled MEC in IoT networks compared to the existing baselines.
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