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排序方式: 共有2285条查询结果,搜索用时 15 毫秒
51.
嵌入式SRAM的优化修复方法及应用 总被引:2,自引:1,他引:1
为了提高SRAM的成品率并降低其功耗,提出一种优化的SRAM.通过增加的冗余逻辑及电熔丝盒来代替SRAM中的错误单元,以提高其成品率;通过引入电源开启或关闭状态及隔离逻辑降低其功耗.利用二项分布计算最佳冗余逻辑,引入成品率边界因子判定冗余逻辑的经济性.将优化的SRAM64K×32应用到SoC中,并对SRAM64K×32 的测试方法进行了讨论.该SoC经90nm CMOS工艺成功流片, 芯片面积为5.6mm×5.6mm, 功耗为1997mW.测试结果表明:优化的SRAM64K×32 在每个晶圆上的成品率提高了9.267%,功耗降低了17.301%. 相似文献
52.
Zhao-Yang Yin Yang Chen Yang-Yang Zhang Yu Yuan Qian Yang Ya-Nan Zhong Xu Gao Jing Xiao Zhao-Kui Wang Jian-Long Xu Sui-Dong Wang 《Advanced functional materials》2023,33(33):2302199
Minimizing reverse bias dark current density (Jdark) while retaining high external quantum efficiency is crucial for promising applications of perovskite photodiodes, and it remains challenging to elucidate the ultimate origin of Jdark. It is demonstrated in this study that the surface defects induced by iodine vacancies are the main cause of Jdark in perovskite photodiodes. In a targeted way, the surface defects are thoroughly passivated through a simple treatment with butylamine hydroiodide to form ultrathin 2D perovskite on its 3D bulk. In the passivated perovskite photodiodes, Jdark as low as 3.78 × 10-10 A cm-2 at -0.1 V is achieved, and the photoresponse is also enhanced, especially at low light intensities. A combination of the two improvements realizes high specific detectivity up to 1.46 × 1012 Jones in the devices. It is clarified that the trap states induced by the surface defects can not only raise the generation-recombination current density associated with the Shockley–Read–Hall mechanisms in the dark (increasing Jdark), but also provide additional carrier recombination paths under light illumination (decreasing photocurrent). The critical role of surface defects on Jdark of perovskite photodiodes suggests that making trap-free perovskite thin films, for example, by fine preparation and/or surface engineering, is a top priority for high-performance perovskite photodiodes. 相似文献
53.
Kexin Wang Junhui Cao Xiaoxuan Yang Xiahan Sang Siyu Yao Rong Xiang Bin Yang Zhongjian Li Thomas O'Carroll Qinghua Zhang Lecheng Lei Gang Wu Yang Hou 《Advanced functional materials》2023,33(16):2212321
Designing hydrogen evolution reaction (HER) electrocatalysts for facilitating its sluggish adsorption kinetics is crucial in generating green hydrogen via sustainable water electrolysis. Herein, a high-performance ultra-low Ruthenium (Ru) catalyst is developed consisting of atomically-layered Ru nanoclusters with adjacent single Ru sites, which executs a bridging-Ru-H activation strategy to kinetically accelerate the HER elementary steps. Owing to its optimal electronic structure and unique adsorption configuration, the hybrid Ru catalyst simultaneously displayed a drastically reduced overpotential of 16 mV at 10 mA cm−2 as well as a low Tafel slope of 35.2 mV dec−1 in alkaline electrolyte. When further coupled with a commercial IrO2 anode catalyst, the ensembled anion-exchange membrane water electrolyzer achievs a current density of 1.0 A cm−2 at a voltage of only 1.70 Vcell. In situ spectroscopic analysis verified that Ru single atom and atomically-layered Ru nanoclusters in the hybrid materials play a critical role in facilitating water dissociation and weakening *H adsorption, respectively. Theoretical calculations further elucidate the underlaying mechanism, suggesting that the dissociated proton at the single atom Ru site orients itself adjacently with Ru nanoclusters in a bridged structure through targeted charge transfer, thus promoting Volmer-Heyrovsky dynamics and boosting the HER activity. 相似文献
54.
Jine Zhang Xiaobing Chen Mengqin Wang Qinghua Zhang Wenxiao Shi Xiaozhi Zhan Meng Zhao Zhe Li Jie Zheng Hui Zhang Furong Han Huaiwen Yang Tao Zhu Banggui Liu Fengxia Hu Baogen Shen Yuansha Chen Yue Zhang Yunzhong Chen Weisheng Zhao Jirong Sun 《Advanced functional materials》2023,33(41):2306434
Ferromagnetic materials with a strong spin-orbit coupling (SOC) have attracted much attention in recent years because of their exotic properties and potential applications in energy-efficient spintronics. However, such materials are scarce in nature. Here, a proximity-induced paramagnetic to ferromagnetic transition for the heavy transition metal oxide CaRuO3 in (001)-(LaMnO3/CaRuO3) superlattices is reported. Anomalous Hall effect is observed in the temperature range up to 180 K. Maximal anomalous Hall conductivity and anomalous Hall angle are as large as ∼15 Ω−1 cm−1 and ∼0.93%, respectively, by one to two orders of magnitude larger than those of the typical 3d ferromagnetic oxides such as La0.67Sr0.33MnO3. Density functional theory calculations indicate the existence of avoid band crossings in the electronic band structure of the ferromagnetic CRO layer, which enhances Berry curvature thus strong anomalous Hall effects. Further evidences from polarized neutron reflectometry show that the CaRuO3 layers are in a fully ferromagnetic state (∼0.8 μB/Ru), in sharp contrast to the proximity-induced canted antiferromagnetic state in 5d oxides SrIrO3 and CaIrO3 (∼0.1 μB/Ir). More than that, the magnetic anisotropy of the (001)-(LaMnO3/CaRuO3) superlattices is eightfold symmetric, showing potential applications in the technology of multistate data storage. 相似文献
55.
56.
Tamaki Naganuma 《Nano Research》2017,10(1):199-217
Cerium oxide nanoparticles (CONPs), widely used in catalytic applications owing to their robust redox reaction, are now being considered in therapeutic applications based on their enzyme mimetic properties such as catalase and super oxide dismutase (SOD) mimetic activities. In therapeutic applications, the emerging demand for CONPs with low cytotoxicity, high cost efficiency, and high enzyme mimetic capability necessitates the exploration of alternative synthesis and effective material design. This study presents a room temperature aqueous synthesis for low-cost production of shape-selective CONPs without potentially harmful organic substances, and additionally, investigates cell viability and catalase and SOD mimetic activities. This synthesis, at room temperature, produced CONPs with particular planes: {111}/{100} nanopolyhedra, {100} nano/submicron cubes, and {111}/{100} nanorods that grew in [110] longitudinal direction. Enzymatic activity assays indicated that nanopolyhedra with a high concentration of Ce4+ ions promoted catalase mimetic activity, while nanocubes and nanorods with high Ce3+ ion concentrations enhanced SOD mimetic activity. This is the first study indicating that shape and facet configuration design of CONPs, coupled with the retention of dominant, specific Ce valence states, potentiates enzyme mimetic activities. These findings may be utilized for CONP design aimed at enhancing enzyme mimetic activities in therapeutic applications. 相似文献
57.
Yuping Jia Xiaojuan Sun Zhiming Shi Ke Jiang Henan Liu Jianwei Ben Dabing Li 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(26)
Silicon carbide (SiC) with epitaxial graphene (EG/SiC) shows a great potential in the applications of electronic and photoelectric devices. The performance of devices is primarily dependent on the interfacial heterojunction between graphene and SiC. Here, the band structure of the EG/SiC heterojunction is experimentally investigated by Kelvin probe force microscopy. The dependence of the barrier height at the EG/SiC heterojunction to the initial surface state of SiC is revealed. Both the barrier height and band bending tendency of the heterojunction can be modulated by controlling the surface state of SiC, leading to the tuned carrier transport behavior at the EG/SiC interface. The barrier height at the EG/SiC(000‐1) interface is almost ten times that of the EG/SiC(0001) interface. As a result, the amount of carrier transport at the EG/SiC(000‐1) interface is about ten times that of the EG/SiC(0001) interface. These results offer insights into the carrier transport behavior at the EG/SiC heterojunction by controlling the initial surface state of SiC, and this strategy can be extended in all devices with graphene as the top layer. 相似文献
58.
The formation of all‐organic dual spin valves (DSVs) with three organic spin‐selective layers, that is, spin‐injection, spin‐detection, and an additional spin‐filtering layer at the intermediate, is reported. As spin‐selective layers, manganese‐ and cobalt phthalocyanines, which are well‐known single‐molecule magnets, are used in their immobilized forms, so that all‐organic DSVs can be prefabricated for characterization. The three spin‐selective layers have provided four configurations with at most two spin‐flip interfaces enforcing spin‐flipping at the two nonmagnetic organic spacer layers, for which copper phthalocyanine is used. Since a couple of the four configurations have exhibited similar resistivities, the degeneracy in the resistive‐states is broken through asymmetric spin‐injection and spin‐detection layers and also through asymmetric thickness of the nonmagnetic spacer layers. When both the spin‐flip interfaces are made operative independently, a 2‐bit logic with four distinct resistive states can be achieved. 相似文献
59.
为研究非晶态合金Co-Fe-P体系的成键方式及磁性,在较高的量子化学水平下,利用密度泛函理论,以团簇Co3FeP为局域模型展开研究,结果发现:团簇的自旋多重度和几何形态均会影响其成键杂化方式和磁性;团簇Co3FeP中存在pd2、s2p2d3、p2d、p3d、p3、pd3杂化,其中Co-Fe键主要由Co3d和Fe3d、Co4p和Fe4p形成的d2和p2杂化组成;Co-P键主要是Co3d和P3p形成的pd杂化;Fe-P键主要是Fe3d和P3p形成的pd杂化。Co原子和Fe原子在提供磁性时,相互制衡。综合来看,d轨道对团簇Co3FeP的成键方式和磁性有着重要影响。 相似文献
60.
本文刻画了标记配对相干态光源(HPCS光源)光子数分布的两条性质,基于三强度诱骗态编码方案,证明了HPCS光源满足强度涨落下量子密钥分配最终密钥生成率表达式的条件.数值模拟表明,HPCS光源的三强度诱骗态编码方案与理想方案(无穷诱骗态)的接近程度较高,该光源对强度涨落的稳定性要好于弱相干态光源,但明显比标记单光子源要弱... 相似文献