- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- 2018
- JBSFET
- Robustness
- MOSFET
- Reliability
- Silicon Carbide
- 4H-SiC
- Failure Mechanism
- Short Circuit
- Ruggedness
- silicon photonics
- Electrical Engineering and Automation
- Optoelectronic Information Science and Engineering
- Electronic Science and Technology
- North Carolina State University
- MediaTek, Inc.
- JCET STATS ChipPAC Pte. Ltd.
-
Structural and optical studies of gamma irradiated N-doped 4H-SiC
摘要： In this paper, the gamma irradiation effects on the structural and optical properties of N-doped 4H-SiC (n-4H-SiC) is presented up to a cumulative gamma radiation dose of 1500 kGy. The studies showed marginal and inconsistent variation in the - and -axis lattice constants of 4H-SiC due to the accumulation of gamma-induced defect states. The modifications in the longitudinal optical plasmon-phonon coupled (LOPC) modes, Biedermann absorption bands, Urbach energy ( ) and defect related photoluminescence (DPL) bands are discussed at different (500, 1000 and 1500 kGy) irradiation doses. Despite these effects, the overall gamma-induced disorder ( ) and variation in the free carrier concentrations ( ) are found to be negligible and demonstrating the radiation resistant property of n-4H-SiC under gamma radiation environment.
关键词： PL,Silicon carbide,XRD,LOPC modes,Gamma irradiation
更新于2025-09-04 15:30:14
-
25 nm Single-Crystal Silicon Nanowires Fabricated by Anisotropic Wet Etching
摘要： We report a top-down method for fabricating ultra-high aspect ratio single-crystal silicon nanowires. The fabrication method is based on the standard photolithography technique and anisotropic wet etching of the single-crystal silicon in KOH solution. SiO2 mask nanolines used for patterning single-crystal silicon nanowires are formed by the undercut etching of thin SiO2 layer in buffered hydrofluoric solution. The minimum width of the SiO2 mask nanolines are 50 nm. The length of SiO2 mask nanolines is 2 cm. The single-crystal silicon nanowires have been successfully transferred from the SiO2 mask nanolines by KOH anisotropic wet-chemical etching. The minimum width of the silicon nanowire has obtained to be 25 nm. The fabricated single-crystal silicon nanowires have trapezoidal and triangular cross sections, which are useful for applications in nanoelectronic and nanophotonic elements.
关键词： All Wet Chemical Etching,Wafer-Scale Fabrication,Single-Crystal Silicon Nanowire,Photolithography
更新于2025-09-04 15:30:14
-
Improvement in Resistance Switching of SiC-Based Nonvolatile Memory by Solution-Deposited HfO <sub/><i>x</i> </sub> Thin Film
摘要： In this study, we implemented a resistance change memory (ReRAM) device using a SiC layer with excellent physical properties. We fabricated devices composed of Ti/SiC/Pt and Ti/HfOx/SiC/Pt structures and investigated their memory characteristics. The Ti/SiC/Pt ReRAM devices exhibited stable bipolar resistive switching characteristics but had a relatively small memory window, whereas the Ti/HfOx/SiC/Pt ReRAM devices had a large memory window and low operating voltage. In addition, the Ti/HfOx/SiC/Pt ReRAM devices exhibited stable endurance characteristics over 500 cycles and excellent retention characteristics at room temperature and high temperatures for 1 × 104 s. Further, the Ti/HfOx/SiC/Pt ReRAM devices exhibited multi-level conduction states by modulating the reset stop voltage, and each resistance level had excellent endurance characteristics. The average transmittance of the HfOx/SiC bilayer in visible light was 87%. Such a high value indicates that the HfOx/SiC bilayer fabricated by the stacking method is expected to be a suitable material for highly reliable nonvolatile memory and transparent electronic devices, even in harsh environments.
关键词： Bilayer,ReRAM,BRS,Silicon Carbide,Multi-Level Cell (MLC)
更新于2025-09-04 15:30:14
-
[IEEE 2018 48th European Microwave Conference (EuMC) - Madrid, Spain (2018.9.23-2018.9.27)] 2018 48th European Microwave Conference (EuMC) - A Scalable Dual-Polarized 256-Element Ku-Band SATCOM Phased-Array Transmitter with 36.5 dBW EIRP Per Polarization
摘要： This paper presents a Ku-band dual-polarized transmit phased-array with 256-elements spaced λ/2 apart at 14 GHz in the x and y directions. The design is based on 64 silicon quad-core transmit chips with 8 channels, and these chips are used to feed a 2x2 quad antennas with dual polarizations. The output P1dB per channel is 12 dBm at 14 GHz. The silicon core-chips are flipped directly on a 12-layer low-cost printed circuit board (PCB) with stacked patch antennas and Wilkinson dividers. The 256-element phased-array results in a measured EIRP of 64.5 dBm and 66.5 dBm at P1dB and Psat, respectively, at normal incidence, per polarization. Measured patterns show a scan region of ±60° in E- and H-planes with low sidelobes and near-ideal patterns. The design achieves a cross polarization level < -27 dB up to ±45° and < -23 dB at ±60° scan angle, in both planes. The array is scalable to allow the construction of large-scale phased-arrays (1024 elements or more). To our knowledge, this represents state-of-the-art in Ku-band transmit phased-arrays in terms of integration level making it suitable for a low-cost mobile Ku-band SATCOM terminal.
关键词： silicon,phased arrays,transmit,SATCOM,antenna,beamforming,Ku-Band,PCB,14 GHz,SiGe,flip-chip
更新于2025-09-04 15:30:14
-
Controllable coating polypyrrole on silicon carbide nanowires as a core-shell nanostructure: a facile method to enhance attenuation characteristics against electromagnetic radiation
摘要： Continuous polypyrrole (PPy) shells were coated on silicon carbide (SiC) nanowires to form core-shell nanostructures and the thicknesses of the shells were efficiently tuned through controlling the rate of polymerization. Compared with the composites loaded with pure SiC nanowires, the values of ε′ and ε′′ for the composites loaded with PPy@SiC nanowires were strengthened remarkably along with the increased thickness of the shells. The electromagnetic absorption (EA) bandwidth lower than ?10 and ?20 dB can be monitored in the area of 3.67-18.00 and 4.13-18.00 GHz, when 5 wt% of PPy@SiC nanowires were loaded in the composite. Meanwhile, the effective EA bandwidth can reach 6.88 GHz and the strongest reflection loss is ?58.6 dB.
关键词： dielectric properties,polypyrrole,silicon carbide nanowires,core-shell nanostructures,electromagnetic absorption
更新于2025-09-04 15:30:14
-
Time-of-flight spectrometry of ultra-short, polyenergetic proton bunches
摘要： A common approach for spectrum determination of polyenergetic proton bunches from laser-ion acceleration experiments is based on the time-of-flight (TOF) method. However, spectra obtained using this method are typically given in relative units or are estimated based on some prior assumptions on the energy distribution of the accelerated ions. In this work, we present a new approach using the TOF method that allows for an absolute energy spectrum reconstruction from a current signal acquired with a sub-nanosecond fast and 10 μm thin silicon detector. The reconstruction is based on solving a linear least-squares problem, taking into account the response function of the detection system. The general principle of signal generation and spectrum reconstruction by setting up an appropriate system response matrix is presented. Proof-of-principle experiments at a 12 MV Tandem accelerator using different nanosecond-short (quasi-)monoenergetic and polyenergetic proton bunches at energies up to 20 MeV were successfully performed. Within the experimental uncertainties of 2.4% and 12.1% for energy and particle number, respectively, reconstructed energy distributions were found in excellent agreement with the spectra calculated using Monte Carlo simulations and measured by a magnetic spectrometer. This TOF method can hence be used for absolute online spectrometry of laser-accelerated particle bunches.
关键词： silicon detector,time-of-flight spectrometry,energy spectrum reconstruction,polyenergetic proton bunches,laser-ion acceleration
更新于2025-09-04 15:30:14
-
The stability and electronic properties of Si-doped ZnO nanosheet: A DFT study
摘要： This work deals with stability, structural and electronic properties of perfect ZnO nanosheet and substiutionally doped ZnO nanosheet with Si are simulated and optimized successfully using density functional theory (DFT) with the help of SIESTA program in the generalized gradient approximation (GGA). The substitution atoms have been replaced on the oxygen site in line and zigzag doping. The stability of perfect ZnO nanosheet and ground state structures of Sin-ZnO (n=1-6) are studied in terms of binding energy, show that a maximum stabilized of one Si in line doping and two Si in zigzag doping due to the dopant located in the center of nanosheet is a more stable. The electronic properties of ZnO nanosheet and Si-doped are discussed using ionization potential, electron affinity, HOMO–LUMO gap, electronegativity, and hardness. The results showed the presence of silicon atoms substitution expands the bond length with respect to perfect ZnO nanosheets. The obtained values of HOMO and LUMO are slightly different and this suggests that different of position dopant play significant roles on electronic properties and large electron affinity at four silicon atoms doped ZnO nanosheet in two cases that it improved the electron more accepting ability. The study of HOMO-LUMO gap reveals that the gap decreases with the increase in number of Si dopant atoms in ZnO nanosheet. These results global gave molecular electronics important electronic applications and help us to replace some oxygen atoms instead of silicon atoms in ZnO nanosheet.
关键词： ZnO nanosheet,Silicon-doping,Electronic property.,Line & zigzag doping
更新于2025-09-04 15:30:14
-
Heterogeneous Twinning during directional solidification of multi-crystalline silicon
摘要： Heterogeneous twinning nucleation from the wall or gas interface during directional solidification of silicon have been modelled, and further used to clarify the details of twining observed in situ in X-ray synchrotron imaging experiments [1]. It is found that the heterogeneous twinning from the wall/grains or wall/gas/grain trijunctions requires much lower undercoolings leading to much higher twinning probability. The lower attachment energy and the contact area are the key factors for the heterogeneous nucleation of twins.
关键词： B2. Silicon,A1. Heterogeneous,A1. Twinning,A1. Undercooling,A1. Nucleation,A1. Facets
更新于2025-09-04 15:30:14
-
Spin–orbit coupling in silicon for electrons bound to donors
摘要： Spin–orbit coupling (SOC) is fundamental to a wide range of phenomena in condensed matter, spanning from a renormalisation of the free-electron g-factor, to the formation of topological insulators, and Majorana Fermions. SOC has also profound implications in spin-based quantum information, where it is known to limit spin lifetimes (T1) in the inversion asymmetric semiconductors such as GaAs. However, for electrons in silicon—and in particular those bound to phosphorus donor qubits—SOC is usually regarded weak, allowing for spin lifetimes of minutes in the bulk. Surprisingly, however, in a nanoelectronic device donor spin lifetimes have only reached values of seconds. Here, we reconcile this difference by demonstrating that electric ?eld induced SOC can dominate spin relaxation of donor-bound electrons. Eliminating this lifetime-limiting effect by careful alignment of an external vector magnetic ?eld in an atomically engineered device, allows us to reach the bulk-limit of spin-relaxation times. Given the unexpected strength of SOC in the technologically relevant silicon platform, we anticipate that our results will stimulate future theoretical and experimental investigation of phenomena that rely on strong magnetoelectric coupling of atomically con?ned spins.
关键词： silicon,spin relaxation,Spin–orbit coupling,donor-bound electrons,quantum information
更新于2025-09-04 15:30:14
-
Uniform Metal-Assisted Chemical Etching for Ultra-High-Aspect-Ratio Microstructures on Silicon
摘要： Recently, uniform metal-assisted chemical etching (UMaCE) has been demonstrated as an effective wet etch method for fabrication of deep trenches and holes on silicon (Si). However, attempts to achieve higher aspect ratio by UMaCE was not successful because etching in random directions was observed. In this paper, the etching uniformity in UMaCE is systematically studied at different etching solution composition and catalyst configuration. The surface chemistry evolution of Si during etching is characterized by X-ray photoelectron spectroscopy, water contact angle, and electrical impedance spectroscopy. Based on the data, the reaction kinetics is analyzed, which shows that an electropolishing-type charge transport and a higher amount of oxide species on Si surface help mitigate the random etching behavior and effectively promote the aspect ratio of the etching with uniformity. Under the rationalized condition, uniform trenches with width of 2 μm and aspect ratio of 120:1 is successfully fabricated by UMaCE.
关键词： Metal-assisted chemical etching,silicon wet etch,high aspect ratio.
更新于2025-09-04 15:30:14