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91.
92.
测试半导体GaN功率开关器件灵敏度对掌握器件性能具有重要意义,提出一种新的半导体GaN功率开关器件灵敏度测试技术。通过分析半导体GaN功率开关器件的导通电阻与击穿电压关系、空穴电流与栅极电流关系掌握功率开关器件击穿机理,在此基础上,测试半导体GaN功率开关器件灵敏度;根据灵敏度测试原理与微频通道衰减值周期检查原理,测量功率开关器件微频信号功率和微频通道衰减值,汇总微频通道衰减值和最后一次开关灵敏时的衰减值,得到半导体GaN功率开关器件灵敏度。实验结果表明:所提测试技术测量半导体GaN功率开关器件灵敏度过程中,平均测试误差为0.03 dB,仅平均花费9.42ms,是一种高效、可靠的半导体GaN功率开关器件灵敏度测试技术。 相似文献
93.
本文简要介绍了脲醛树脂基高分子材料的基本生产工艺流程,探索玻璃纤维、纳米蒙脱土、丁腈橡胶粉以及玉米淀粉种类和用量对脲醛树脂基高分子材料耐电击穿性能的影响。实验结果表明,选用玻璃纤维作为增强剂对脲醛树脂基高分子材料的耐电击穿强度影响最为明显,纳米蒙脱土次之,玉米淀粉的加入对脲醛树脂基高分子材料的耐电击穿强度影响不明显,而丁腈橡胶的加入对脲醛树脂基高分子材料的耐电击穿强度有明显的下降趋势,改性后的脲醛树脂基高分子材料的耐电击穿强度能超过17KV/mm,最佳耐压时间在100s以上。 相似文献
94.
Copper transport in damascene interconnect structures is an important reliability issue leading to accelerated interlayer dielectric (ILD) breakdown. It is unclear that whether the experimentally determined leakage current is mainly of an ionic nature or an electronic nature due to the difficulties and complications in separating these two components. However, enough thermodynamic data are available to calculate the copper ionic current from basic transport equations and independently determined parameter values. The calculated ionic current is compared with the experimentally determined total current. We have found that the electronic current rather than the ionic current is the major component in the leakage current. 相似文献
95.
项目管理技术在行业制造过程管理中的应用研究 总被引:8,自引:0,他引:8
适应行业制造管理的需求,提出了将项目管理技术应用到面向行业的产品制造过程管理中的模式。重点讨论了项目管理技术与行业制造过程管理结合的必然性、可行性和利用项目管理技术对产品制造过程进行管理的内容与手段。 相似文献
96.
《Ceramics International》2019,45(12):14684-14690
(Ca0.5Sr0.5)1-1.5xLaxTiO3 (x = 0.000, 0.050, 0.075, 0.100, 0.150) ceramics were successively fabricated by conventional solid state method. Structure characterization were detected by XRD and SEM, demonstrating the influence of La2O3 doping on the microstructure. In addition, this effect on relaxor behavior corresponding to resistivity of grain boundary was discussed by dielectric and impendance spectra. The determining band gap energy (Eg) was estimated by Ultraviolet–Visible Spectrophotometry in order to investigate the effect of band gap on the breakdown strength. The dielectric breakdown strength was found to significantly enhanced on the basis of Ca0.5Sr0.5TiO3 ceramics with La2O3 doping, the (Ca0.5Sr0.5)0.8875La0.075TiO3 samples possessed widest band gap (∼5.2 eV) and exhibited maximum breakdown strength of 370 kV/cm corresponding with a large recoverable energy storage density of 2.07 J/cm3. Furthermore, the excellent stability of energy storage properties and ultrahigh energy efficiency of above 93% at wide frequency (1–1000 Hz) as well as high temperature (20–180 °C) was obtained for (Ca0.5Sr0.5)0.8875La0.075TiO3 ceramics, which reveal samples as good candidate for linear energy storage fileds. 相似文献
97.
《Journal of the European Ceramic Society》2020,40(15):5589-5596
Silver niobate AgNbO3 ceramics have been regarded as a promising lead-free material for energy storage applications. In present work, pure and fine AgNbO3 powders were successfully fabricated via the hydrothermal method using AgNO3 as the raw material. It is found that the reaction products show strong dependence on the molar ratio of NH4HF2:AgNO3:Nb2O5, pH value and reaction time. Pure AgNbO3 powders were obtained when the process conditions are 3NH4HF2:2AgNO3:xNb2O5 with x≤0.85 or yNH4HF2:2AgNO3:1Nb2O5 with y = 4–5, pH = 5 and reaction time t ≥ 10 h. Benefitting from the hydrothermal synthesised AgNbO3 powders, AgNbO3 ceramics with fine-grain of ∼3.4 μm were obtained. The fine-grain leads to increased electric breakdown strength Eb up to 250 kV/cm, which is the highest among the pure AgNbO3 ceramics to our best knowledge. The further enhancement in Eb and recoverable energy density could be highly anticipated if the antiferroelectric phase could be stabilized. 相似文献
98.
《Journal of the European Ceramic Society》2020,40(8):3343-3347
Dielectric materials with high power density, fast charge and discharge rates, and high energy-storage density are urgently required due to the rapid development of hybrid vehicles and pulse power boosting technology. In this work, the novel environment-friendly (1-x)(Ba0.8Sr0.2)TiO3-xBi(Zn2/3Nb1/3)O3 (0.04 ≤ x ≤ 0.16) [(1-x)BST-xBZN] ceramics were designed and synthesized by traditional solid-state reaction method, exhibiting ultrahigh energy efficiency and super stability against temperature. The results show that the recoverable energy density (Wrec) and the energy efficiency (η) of the (1-x)BST-xBZN ceramics are increase sharply then decrease slightly with increasing of x value. The 0.88BST-0.12BZN ceramic demonstrated a recoverable energy density of ≈ 1.62 J/cm3 and an extreme high energy efficiency of ∼ 99.8 % at 225 kV/cm at room temperature. These extreme high efficiency and high breakdown strength would make (Ba,Sr)TiO3-based lead-free ceramic systems might be good candidate for high power energy-storage applications pulsed power systems. 相似文献
99.
100.
简述了HD-2型汽轮鼓风机组在线监测与故障诊断系统的构成、功能及应用效果.为大型旋转机械的在线监测提供了一种参考方法。 相似文献