Evaluating k-values for low-k materials after damascene integration: Method and results

This work discusses a method for measuring k-values of low-k films after integration in damascene structures. The experimental results are obtained from 90 nm ½ pitch single damascene structures on low-k materials with intrinsic k-values ranging between 2.2 and 3. The measurement technique is discussed in detail with a focus on the accuracy, limitation of the method, impact of low-k damage and applicability for smaller dimensions.     

Capacitance effect on Co-layer dissolution during pulse potentiostatic deposition of Co-Cu/Cu multilayers

Electrodepositon of Co-Cu/Cu multilayer was carried out employing two-pulse potentiostatic method from a sulphate based single solution electrolyte. Dissolution characteristics of thin Co-layer preceding a Cu-layer, were investigated using chronoamperometry, chronocolumetry and electrochemical quartz crystal microbalance (EQCM) techniques. Both galvanic displacement due to Cu²⁺ ions and cell capacitance effect were found to be responsible for the dissolution of Co-layer during pulse switchover from Co to Cu-discharge. Competitive effect of these two factors on Co-dissolution was found to depend solely on the choice of discharge potential pair of Cu and Co. Co-layer dissolution could be prevented on application of Cu-discharge potential very close to the point of onset of Co-reduction potential. An effort has been made to understand the thickness loss due to capacitance effect by adopting a double layer model. It was also seen that the Cu-layer formed due to galvanic displacement reaction was porous in nature, and allows the Co-layer underneath to corrode for several nanometers upon allowance.     

土壤相对湿度与电容相关性探究

土壤相对湿度是农业自动化灌溉技术的关键性指标,也是当前农田领域研究的热点问题。为了探索土壤电容与土壤相对湿度的相关性,设计了一种测量土壤电容值的方法,通过烘干法对不同湿度点进行了较为精准的电容值检测,最后通过matlab7.1作数据拟合。结果表明,土壤电容值与土壤相对湿度在30%-100%之间存在很好的对数关系,考虑温度补偿,得到任意温度t的湿度t=(17.53ln Cx-5.773)*(100+0.05075*(20-t))%,判定系数R2=0.975。     

多层介质中多导体拐角结构电容参数的提取

本文给出一种计算多层介质中多导体拐角互连结构的准静态电容参数的快速算法─—维数缩减技术（DRT），并和有限差分法相结合，快速、准确地提取了多层介质中多导体拐角结构的准静态电容矩阵。由于维数缩减技术能充分利用集成电路结构分层的特点，从而大大减少了计算所需的时间和存储空间。文中给出的计算结果与Ansoft软件的计算结果吻合得较好，而计算所需的时间和存储空间大大少于Ansoft软件。     

认识电阻、电容、电感及如何选用LCR电桥

在不同频率的电路中，LCR的等效电路、应用以及正确使用LCR电桥测试的方法。     

基于边界元法的二维VLSI版图电容提取

提出了一种用边界元法计算ＶＬＳＩ版图电容的方法，通过求解二维拉普拉斯方程，直接得到版图中各种类型的电容的值。该方法提取数据准确简单，占用内存少，计算效率高，且有较高的精度。用该方法对几种典型的ＶＬＳＩ版图电容进行提取，均取得较好的结果。     

On the electrochemical response and interfacial properties of steel-Ca(OH)2 and the steel-concrete system measured using galvanostatic pulses

The interfacial properties of the steel-concrete system are examined via a new approach for evaluation of galvanostatic pulse data. This methodology allows for rapid determination of the corrosion activity of steel, and readily yields values for parameters related to corrosion such as the polarisation resistance and interfacial capacitance. The method of analysis is based on the iterative fitting of a non-exponential model based on a modified Kohlrausch-Williams-Watt (KWW) formalism. The transient behaviour of steel in concrete is non-exponential in its form and, when analysed this way, an exponent β can be determined characterising the exponential non-ideality of the transient. This non-ideality parameter is found to differ significantly for actively corroding and passive specimens, thereby serving as a useful index to the level of corrosion being experienced. Furthermore, the investigation of the interfacial characteristics of the system, previously unobtainable in a reproducible manner via other electrochemical methods, reveal information regarding the kinetic factors governing corrosion of steel in concrete.     

压风机断水保护的PLC应用

为确保压风机冷却装置不因缺水而失效 ,必须为每台压风机装备断水保护。分析了普通电接点压力表组成的断水保护原理及不足 ,同时对成功应用的PLC断水保护进行总结     

电容式套管卷绕机的S型切割控制技术

本文介绍了电容式套管卷绕电控系统中S型切割控制技术。采用日本三菱公司的FX3U系列可编程控制器(PLC)控制步进电机实现S型切割控制。     

GaAs/Ge solar cell AC parameters under illumination

The ac parameters of GaAs/Ge solar cell were measured under illumination at different cell temperatures using impedance spectroscopy technique. They are compared with the dark measurements. It is found that the cell capacitance is higher and cell resistance is lower under illumination than in dark for all cell terminal voltages. The cell capacitances at the corresponding maximum power point voltage (terminal) do not vary with temperature where as the cell resistance decreases. The cell capacitance under illumination is estimated from the dark cell capacitance and it is in good agreement with the measured illumination data.