- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A roller posture adjustment device with remote-center-of-motion for roll-to-roll printed electronics
摘要: Nonuniform web tension has a great negative effect on product quality of roll-to-roll printed electronics. In this paper, a roller posture adjustment device with remote-center-of-motion (RCM) characteristic is proposed to guarantee web tension uniformity. The device combines a high-stiffness spherical air bearing (SAB) and a multi-degree-of-freedom flexure-based mechanism. The nonuniform web tension in lateral direction can be divided into an equivalent force and two equivalent moments. The equivalent moments are caused by the nonuniformity of the web tension. By adjusting the roller angle around y and z-axes, the equivalent moments can be eliminated to guarantee the web tension uniformity. The multi-DOF flexure-based mechanism is composed of a linear mechanism, a rotary mechanism and a 3-DOF off-plane mechanism. Besides, the RCM characteristic of the proposed device is realized to eliminate extra parasitic movement when the roller posture is changed. Based on pseudo-rigid-body model (PRB-M) method, the theoretical analysis is conducted to evaluate the kinematics, stiffness and dynamics of the device. Moreover, the parameter optimization is conducted to maximize the first two resonance frequencies of the system. After that, finite element analysis is conducted to validate the established models. Finally, a prototype of the proposed device is fabricated performance verification. The experimental results show that the proposed device has a workspace of 10.22 mrad and 8.16 mrad about two working axes with center shifts of the RCM point less than 0.75%, which demonstrate the superior property of the proposed device.
关键词: Flexure-based mechanism,Micro-positioning,Roll-to-roll printed electronics,Remote-center-of-motion
更新于2025-09-23 15:21:21
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Picosecond-Range Avalanche Switching of Bulk Semiconductors Triggered by Steep High-Voltage Pulses
摘要: Experimental observation and numerical simulations of sub-nanosecond avalanche switching of Si and ZnSe bulk semiconductor structures initiated by high-voltage pulses with steep (dU/dt > 10 kV/ns) ramp are reported. The measured switching time is ~100 ps. The switching is sustainable and repetitive and has negligible jitter. Comparison of the experimental and numerical results suggests that after switching, the whole volume of the structure is uniformly ?lled with nonequilibrium electron–hole plasma.
关键词: semiconductor lasers,Power electronics,pulse-power system switches
更新于2025-09-23 15:21:21
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Transparent Conductive Materials (Materials, Synthesis, Characterization, Applications) || Metal Nanowires
摘要: Metal nanowires are one-dimensional entities of metals of either single crystalline or polycrystalline nature [1]. Metal nanowires have attracted tremendous research attention since the last two decades, because of their important applications in plasmonics [2], electronics [3], electrocatalysis [4], and so on. In the past decade, researchers have attempted to coat metal nanowires on a transparent substrate as a transparent conductive ?lm (TCF) [5–7]. The visible light transparency and the conductivity of TCFs on the basis of metal nanowires have improved rapidly, being comparable with the performance of the state-of-the-art indium tin oxide (ITO) TCFs [8–10]. The recognition of the potential applications of metal nanowire TCFs stimulates research zeal for the synthesis of metal nanowires. So far, a range of metal nanowires have been synthesized, including Ag nanowires (AgNWs) [11], Au nanowires (AuNWs) [12], Cu nanowires (CuNWs) [13], and Pt nanowires [14]. Bicomponent metal nanowires, such as Cu@Ni [15], Ag@Au [16], Cu@Ag [17], Ag@Ni [18], and Cu@Pt [19] core@shell nanowires, have also been synthesized. These nanowires have been coated on a substrate to produce TCFs, and the performance has been characterized. At early stage of the research on metal nanowire TCFs, the transparency was lower than 80%, and the sheet resistance was as large as several kΩ to MΩ. Both experimental investigation and theoretical modeling have been extensively carried out to improve the performance of metal nanowire TCFs.
关键词: Core@shell nanowires,Transparent conductive films,Plasmonics,Electronics,Au nanowires,Metal nanowires,Ag nanowires,Cu nanowires,Electrocatalysis
更新于2025-09-23 15:21:21
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[IEEE 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Kyoto, Japan (2018.7.9-2018.7.13)] 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Electron sources based on diamond pin-diodes
摘要: Efficient electron sources are of ongoing interest in particular for space and terrestrial power telecommunications and radar applications. With conventional cathode technology based on thermionic- and field electron emission a novel approach for direct electron emission is realized through a diamond pin diode. Electrons injected into the conduction band of the intrinsic layer of the diode can be released into vacuum with a negative electron affinity surface of the i-layer. The diamond pin diodes were prepared on boron doped (p-type) substrates with (111) surface orientation. A high purity intrinsic and a phosphorus doped diamond layer (n-type, ~400nm thickness) were deposited in dedicated PECVD systems, respectively. An additional contact layer comprised of nanostructured carbon was grown in a dedicated PECVD. The layered device was processed by lithography utilizing an aluminum hard mask to etch mesa structures with diameters ranging from 50μm to 200μm. The final devices were treated in a pure hydrogen plasma to induce the negative electron affinity properties of the i-layer. After an annealing step in high vacuum individual pin diodes were biased in forward current and voltages up to 20V. The observation of light from the diode was attributed to the UV exciton state and indicated bipolar transport. At a diode current of about 80mA an electron emission current of 25μA was observed from a single 200μm diameter diode.
关键词: Diamond,solid state electronics,doping,phosphorus,electron emission,plasma-enhanced chemical vapor deposition,nanostructured carbon,pin diode,single crystal
更新于2025-09-23 15:21:21
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[NanoScience and Technology] Silicene (Prediction, Synthesis, Application) || Electronic and Topological Properties of Silicene, Germanene and Stanene
摘要: In this chapter, we review the recent progress on electronic and topological properties of monolayer topological insulators including silicene, germanene and stanene. We start with the description of the topological nature of the general Dirac system and then apply it to silicene by introducing the spin and valley degrees of freedom. Based on them, we classify all topological insulators in the general honeycomb system. We discuss topological electronics based on honeycomb systems. We introduce the topological Kirchhoff law, which is a conservation law of topological edge states. Field effect topological transistor is proposed based on the topological edge states. We show that the conductance is quantized even in the presence of random distributed impurities. Monolayer topological insulators will be a key for future topological electronics and spin-valleytronics.
关键词: topological Kirchhoff law,silicene,topological insulators,topological electronics,Dirac system,field effect topological transistor,spin and valley degrees of freedom,stanene,quantized conductance,germanene
更新于2025-09-23 15:21:21
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[IEEE 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Kyoto, Japan (2018.7.9-2018.7.13)] 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Cold Cathode Based Microwave Devices for Current and Future Systems
摘要: We report ongoing efforts to achieve reliable field emitter (FE) cathode operation for high current electron beam generation in RF microwave devices. These efforts include testing of cold cathode traveling wave tubes, high average power cathode-only testing, and evaluating cathode emission variation over long operating periods in a microwave device vacuum environment. Finally, looking toward future needs, emittance reduction is being addressed to allow cold cathode operation in the mm-wave frequency regime.
关键词: field emitter array,TWT,traveling wave tube,microwave amplifier,cold cathode,vacuum electronics
更新于2025-09-23 15:21:21
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A Fully Integrated 11.2 mm2 a-IGZO EMG Front-end Circuit on Flexible Substrate Achieving up to 41dB SNR and 29MΩ Input Impedance
摘要: A biopotential front-end circuit is designed and fabricated using a-IGZO TFTs on flexible plastic substrate. Its input chopper provides both noise reduction and Frequency Division Multiplexing among multiple front-ends in an array. Measurements of the front-end at chopping frequencies from 5 to 8 kHz show a gain in the range of 24.9 - 23.1 dB, bandwidth of 5.4 to 5.2 kHz, input noise in the EMG band ranging from 125 μVRM S to 31.4 μVRM S, and an input impedance of 29.6 to 23 M ?. At different chopping frequencies, the SNR in the EMG band is respectively 29, 32.3, 38, 41 dB, enough to monitor Muscle Fibre Conduction velocity. This is achieved in a total area of 11.2 mm2 and with 1.3 mW power consumption. In-vivo recordings of EMG from the forearm of a person using the fabricated front-end and standard gel electrodes have been performed. The measurements show EMG bursts with a maximum amplitude of 1.6 mV, which is within the physiological range for this muscle. The proposed circuit achieves an 8.9X reduction in size compared to previous front-ends fabricated on flexible foil for EMG applications, enabling a spatial resolution in the order of a few millimetres, with great benefit for the diagnosis of neuromuscular disorders.
关键词: IGZO,EMG,flexible electronics,Biomedical circuits,EHG
更新于2025-09-23 15:21:21
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Self-powered flexible electronics beyond thermal limits
摘要: Self-powered flexible electronics using high-performance inorganic materials have been studied and developed for the essence of future electronics due to the thing, lightweight, self-sustainable, and biocompatible characteristics, which can be applied to body sensor network and next generation Internet of Things (IoT). However, most of inorganic materials should be processed in the high-temperature processes such as the semiconductor fabrication, which is not compatible flexible plastic substrates. Therefore, the new approaches must be demonstrated to overcome the thermal limits of previous methodology and achieve the flexible inorganic electronics on various flexible plastic substrates. In this review paper, we introduce the recent progress of technologies to realize flexible and high-performance inorganic electronics on plastic substrates over the thermal limits, i.e., laser-assisted procedure, chemical or mechanical exfoliation approaches. They are compatible not only to flexible plastic substrates but also to conventional device processes. We also explain the novel application devices such as flexible optoelectronics, flexible large-scale integration (LSI) devices, flexible energy harvesters, and flexible sensors using the recent-developed technologies beyond the previous thermal limit. This paper highlights the proper direction to complete future flexible inorganic electronics for high-performance self-powered systems.
关键词: High-temperature process,Self-powered device,Exfoliation,System-on-plastic,Laser technology,Flexible electronics
更新于2025-09-23 15:21:21
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Tuning the Cross-Linker Crystallinity of a Stretchable Polymer Semiconductor
摘要: The cross-linking of conjugated polymers has been demonstrated to be an effective strategy to improve its elastic properties to give deformable semiconductors for plastic electronics. While there have been extensive studies of the structural requirements of the polymer host for good film ductility, no work to date has focused on the relevance of the structural design or chemistry of these cross-linker additives. In this study, urethane groups and tertiary carbon atoms are inserted into the alkyl backbone of perfluorophenyl azide-based cross-linkers to investigate the importance of cross-linker crystallinity with respect to polymer morphology and hence mechanical and electrical properties. Linear cross-linkers with hydrogen bonding from urethane groups readily phase separate and recrystallize in the polymer network to form cross-linked domains that obstruct the strain distribution of the polymer film. Branch cross-linkers with tertiary carbon on the other hand form an evenly cross-linked network in the polymer blend stemming from excellent miscibility and show a 4-fold increase in fracture strain. Furthermore, a stable hole mobility of 0.2 cm2 V?1 s?1 is achieved up to ε = 100%, and a stable hole mobility of 0.1 cm2 V?1 s?1 after 2000 cycles of ε = 25% on fully stretchable organic field-effect transistors.
关键词: cross-linking,deformable semiconductors,cross-linker crystallinity,electrical properties,polymer morphology,elastic properties,plastic electronics,conjugated polymers,mechanical properties
更新于2025-09-23 15:21:21
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Transparent Electronics Using One Binary Oxide for All Transistor Layers
摘要: A novel process is developed in which thin film transistors (TFTs) comprising one binary oxide for all transistor layers (gate, source/drain, semiconductor channel, and dielectric) are fabricated in a single deposition system at low temperature. By simply changing the flow ratio of two chemical precursors, C8H24HfN4 and (C2H5)2 Zn, in an atomic layer deposition system, the electronic properties of the binary oxide (HfxZn1?xO2?δ or HZO) are tuned from conducting, to semiconducting, to insulating. Furthermore, by carefully optimizing the properties of the various transistor HZO layers, all-HZO thin film transistors are achieved with excellent performance on both glass and plastic substrates. Specifically, the optimized all-HZO TFTs show a saturation mobility of ≈17.9 cm2 V?1 s?1, low subthreshold swing of ≈480 mV dec?1, high Ion/Ioff ratio of >109, and excellent gate bias stability at elevated temperatures. In addition, all-HZO inverters with high DC voltage gain (≈470), and all-HZO ring oscillators with low stage delay (≈408 ns) and high oscillation frequency of 245 kHz are demonstrated. This approach presents a novel, simple, high performance, and cost-effective process for the fabrication of indium-free transparent electronics.
关键词: transparent multilayer semiconducting channel,transparent electronics,transparent oxide contacts,thin film,transistors,transparent dielectric oxides
更新于2025-09-23 15:21:21