三峡电站允许地电位升高试验研究(Ⅱ)——继电保护设备的工频耐压特性研究

为了确定提高地网允许电位升高值是否可行，作者在研究了控制电缆的工频耐压特性之后在本文中又研究了继电保护设备的工频耐压特性对该 值的影响，并进行了试验，结果表明，继电器绝缘的工频耐压特性是影响这一数值的关键因素。     

半导体GaN功率开关器件灵敏度测试技术

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。     

脲醛树脂基高分子材料改性研究

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。     

Mechanistic study on interlayer dielectric breakdown in integrated circuits

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.     

项目管理技术在行业制造过程管理中的应用研究

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。     

Enhanced energy storage properties of lead-free (Ca0.5Sr0.5)1-1.5xLaxTiO3 linear dielectric ceramics within a wide temperature range

(Ca_0.5Sr_0.5)_1-1.5xLa_xTiO₃ (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 (E_g) 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 Ca_0.5Sr_0.5TiO₃ ceramics with La₂O₃ doping, the (Ca_0.5Sr_0.5)_0.8875La_0.075TiO₃ 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 (Ca_0.5Sr_0.5)_0.8875La_0.075TiO₃ ceramics, which reveal samples as good candidate for linear energy storage fileds.     

Hydrothermal synthesized AgNbO3 powders: Leading to greatly improved electric breakdown strength in ceramics

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 E_b up to 250 kV/cm, which is the highest among the pure AgNbO₃ ceramics to our best knowledge. The further enhancement in E_b and recoverable energy density could be highly anticipated if the antiferroelectric phase could be stabilized.     

Extreme high energy storage efficiency in perovskite structured (1-x)(Ba0.8Sr0.2)TiO3-xBi(Zn2/3Nb1/3)O3 (0.04 ≤ x ≤ 0.16) ceramics

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)(Ba_0.8Sr_0.2)TiO₃-xBi(Zn_2/3Nb_1/3)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 (W_rec) 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.     

全耗尽SOI LDMOS击穿电压的分析

SOI技术已经成功地应用到功率集成电路中,击穿电压是功率器件一个重要的参数。文章分析了SOI LDMOS的击穿电压与漂移区掺杂浓度的关系,并计算了击穿电压。文中首先定义出漂移区临界掺杂浓度,然后分别给出了实际掺杂浓度高于和低于临界掺杂浓度的击穿电压计算公式。计算结果与文献中给出的数值相吻合,证明了模型的正确性。     

HD-2型汽轮鼓风机组在线监测与故障诊断系统

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。