通信机房无功功率补偿及功率因数改善

目前通信机房低压配电系统无功补偿普遍采用电容柜自动投切系统实现。近年来,这种无功补偿方案暴露出诸多弊端,也酿成不少事故。文中在对一起电容补偿柜烧毁事故进行技术分析的基础上,总结了利用电容器进行无功补偿的不足之处,分析了SVG（静态无功发生器）的基本原理及技术优势,提出了通信机房供电系统采用SVG作为无功补偿的新方案。     

一种基于厚膜陶瓷电容的微位移传感器

为深入研究微纳米环境中物体的受力与运动状态,实现微纳米环境下的位置感知与位移操作,建立纳米尺度下位移、力检测的理论方法,研制了一种基于厚膜陶瓷电容的微位移传感器。通过采用厚膜混合集成工艺将信号处理电路与厚膜电容芯片一体化集成,即用厚膜电路替代PCB电路板,以达到降低由于温度效应和寄生电容等导致的非线性误差,提高传感器的分辨率和稳定性的效果。传感器性能标定实验结果表明,0~1 000nm量程范围内位移检测分辨率优于2nm,传感器稳定性得到显著提高,能够用于检测纳米级微小位移变化量。此外,还从材料物理属性和电路优化设计等方面分析了一体化集成的厚膜电路相对于PCB电路板的优越性。     

Si衬底上具有Poly-Si/SiO2堆叠缓冲层的Pb (Zr0.52Ti0.48)O3 存储电容

在p型Si衬底上沉积多晶硅薄膜和Pb(Zr0.52Ti0.48)O3 (PZT)薄膜形成过渡层。测试淀积在多晶硅上的PZT薄膜不同退火温度的X射线衍射峰。Pt/PZT/poly-Si电容被研究。由于PZT薄膜的铁电极化特性,金属/铁电/多晶硅/二氧化硅/Si结构存储电容在650度退火展示了其顺时针的电压-电容曲线。存储窗口随着SiO2电容和PZT电容的耦合比的增加而增大。     

0.18-mm RF CMOS 工艺电感电容压控振荡器*

采用SMIC 0.18mm RF CMOS工艺设计实现了一种低相位噪声的压控振荡器。该电路采用了优化设计的电感电容谐振腔,差分耦合的放大器作为负阻补偿谐振腔的能量损耗。为了拓宽电路的频率调谐范围,在电路中设计了三比特开关电容阵列。测试结果表明：振荡器频率调谐范围为1.92GHz 到3.35GHz,在2.4GHz 频率处偏移载波1MHz处的相位噪声为-117.8dBc/Hz。电路直流供电电压为1.8V,电流为5.6mA.,芯片尺寸为600mm′900mm。芯片性能良好,可以应用于IEEE802.11b标准的无线局域网接收机中。.     

Gate length dependence of the shallow trench isolation leakage current in an irradiated deep submicron NMOSFET

The effects of gamma irradiation on the shallow trench isolation(STI)leakage currents in a 0.18μm technology are investigated.NMOSFETs with different gate lengths are irradiated at several dose levels.The threshold voltage shift is negligible in all of the devices due to the very thin oxide thickness.However,an increase in the off-state leakage current is observed for all of the devices.We believe that the leakage is induced by the drain-to-source leakage path along the STI sidewall,which is formed by the positive trapped charge in the STI oxide.Also, we found that the leakage is dependent on the device’s gate length.The three-transistor model(one main transistor with two parasitic transistors)can provide us with a brief understanding of the dependence on gate length.     

Pb(Zr_(0.52)Ti_(0.48))O_3 memory capacitor on Si with a polycrystalline silicon/SiO_2 stacked buffer layer

Pb(Zr_(0.52)Ti_(0.48))O_3(PZT) thin films have been deposited on a p-type Si substrate separated by a polycrystalline silicon/SiO_2 stacked buffer layer.The X-ray diffraction peaks of the PZT thin films prepared on the polycrystalline silicon annealed at different temperatures were measured.In addition,the polarization of the Pt/PZT/polycrystalline silicon capacitor has been investigated.The memory capacitor of the metal/ferroelectric/polycrystalline silicon/SiO_2/semiconductor structure annealed at 650℃...     

Novel SEU hardened PD SOI SRAM cell

A novel SEU hardened 10T PD SOI SRAM cell is proposed.By dividing each pull-up and pull-down transistor in the cross-coupled inverters into two cascaded transistors,this cell suppresses the parasitic BJT and source-drain penetration charge collection effect in PD SOI transistor which causes the SEU in PD SOI SRAM. Mixed-mode simulation shows that this novel cell completely solves the SEU,where the ion affects the single transistor.Through analysis of the upset mechanism of this novel cell,SEU performance is roughly equal to the multiple-cell upset performance of a normal 6T SOI SRAM and it is thought that the SEU performance is 17 times greater than traditional 6T SRAM in 45nm PD SOI technology node based on the tested data of the references.To achieve this,the new cell adds four transistors and has a 43.4%area overhead and performance penalty.     

基于数学优化算法的开关电容滤波器电容自动综合

介绍了一种基于数学优化算法的二阶有源开关电容（ＳＣ）标准模块电路级联实现的开关电容滤波器（ＳＣＦ）电容自动综合方法，它克服了传统设计方法动态范围小，敏感度高，电容比大的缺点，可以满意地设计低通，高通，带通和带阻等各种滤波器。     

对寄生电容不灵敏的开关电容有源滤波器的设计

采用单位缓冲器设计对寄生电容不灵敏的开关电容(SC)频率相关负电阻(FDNR)元件，利用该元件对椭圆函数式LC低通滤波器进行SC模拟。为了获得电容最佳值，提出了一种简单的最优化方法；并采用寄生电阻预畸变与SC负电阻相结合的办法，设计的SC滤波器对寄生电容不灵敏，且电路简单。在电子工作平台(EWB)上进行五阶椭圆低通SC-FDNR滤波器仿真，测量数据最大相对误差为0．948％，仿真结果表明该方法实用可行，效果明显。     

Electrochemical characteristics of alumina dielectric layers

The electrochemical characteristics of alumina dielectric layers were studied using a surface roughness factor and an impedance spectroscopy. From the limiting diffusion current method, the surface area factor of the dielectric anodic layer with low electrical conductivity was estimated to be 1.03. As alumina dielectric films on Al have a variable stoichiometry, the electrochemical behavior of Al₂O₃ layer can be monitored by evaluating an equivalent circuit with Young impedance of dielectric constant with a vertical decay of conductivity.