基于像素分布特性的IC晶片视觉检测方法

IC晶片制造过程存在多种致命缺陷,致使芯片失效,导致成品率下降.冗余物缺陷是影响IC晶片成品率下降的重要原因,主要造成电路短路错误.针对冗余物缺陷对版图的影响,提出了一种简单可行的缺陷视觉检测方法,以实现冗余物缺陷的识别及电路失效形式的确定.根据摄取的显微图像的图像特征,利用光线补偿技术及形态滤波方法消除干扰噪声,以提高图像质量,采用投影定理及基于像素分布特性的检测方法,实现电路短路形式或缺陷未导致电路失效的识别.     

GaAs集成电路的金属化缺陷失效定位研究

介绍了一种针对砷化镓集成电路(GaAs IC)金属化缺陷的失效定位方法。首先分析了GaAs IC不同金属化结构(如金属化互连、MIM结构、肖特基接触电极)的光发射显微及光致电阻变化(EMMI/OBIRCH)效应,再结合典型的电路原理,得到可能的电路缺陷模型与EMMI/OBIRCH结果之间的对应关系,从而快速、准确地由EMMI/OBIRCH图像得到金属化开路或者短路失效位置。案例研究结果表明,该方法可用于GaAs IC的失效定位,例如放大器、高速数字驱动电路、射频开关等,适用的失效模式包括基极金属化台阶断裂、源极金属通孔开裂形成的开路或MIM金属化桥连形成的低阻等。     

三维集成电路中硅通孔缺陷建模及自测试/修复方法研究

硅通孔(Through Silicon Via, TSV)是3维集成电路(3D IC)进行垂直互连的关键技术,而绝缘层短路缺陷和凸点开路缺陷是TSV两种常见的失效形式。该文针对以上两种典型缺陷建立了TSV缺陷模型,研究了侧壁电阻及凸点电阻与TSV尺寸之间的关系,并提出了一种基于TSV缺陷电阻端电压的检测方法。同时,设计了一种可同时检测以上两种缺陷的自测试电路验证所提方法,该自测试电路还可以级联起来完成片内修复功能。通过分析面积开销可得,自测试/修复电路在3D IC中所占比例随CMOS/TSV工艺尺寸减小而减小,随TSV阵列规模增大而减小。     

MCM基板电路中的短路和断路的自动光学检测算法

介绍了MCM基板自动光学检测算法。该算法包括二值化处理,数学形态学中的开运算和闭运算、骨架化算法,以及特征提取和特征比对。该算法能够快速准确地抽取MCM基板电路中的主要特征,并且在有效放大短路和断路特征之后检测出缺陷。     

用于多层陶瓷电路板故障定位的红外成像以及电感与电容的测量

现已研究出对多层陶瓷电路板内层线条之间短路和线条中开路作精确定位的方法.短路是通过红外热成像法来定位的,使电流通过短路线条形成的回路便可产生热量.此外,还可通过测量短路线条形成的回路电感来定位。开路是通过测量短路线条形成的回路电感来定位。开路是通过测量开路线条与电路板外表面的接地平面之间的电容来定位。组件的破坏性物理分析曾确认缺陷位置,并显示出这些快速而容易地为电路故障定位所用技术的价值。红外成像法可将短路定位到大约0.25mm之内,甚至还可为若干层敷金属的氧化铝下面埋置的线条定位,只要清除低发射率底面金属和对电流施加脉冲.红外热成像法的主要缺点是需用来产生热像的功率达几百数量级的mW,这样会造成导致烧毁的短路。短路定位的电感测量法和开路定位的电容测量法都是非破坏性的,它们可将故障定位到1mm之内,不过,方法的精确度取决于组件材料的均匀度和几何尺寸。电路板的破坏性物理分析是通过玻璃的超声辅助蚀刻来完成的.蚀刻图形缺陷、Ti-W和Au金属化层的局部熔融、用来限定金属化的相减蚀刻期间产生的金属底割和金属粘结不良是失效的主要原因.多层电路板可用各种技术来对复杂电路进行高密度封装.当多层电路板组装期间或组装之后出现失效时,失效可能难于诊断,因为     

用白光空间滤波系统检查IC掩模缺陷

本文介绍一种使用空间滤波的实时单一镜头白光信息处理系统来检查IC光刻掩模缺陷的方法。采用这种方法比传统的镜检法或激光相干处理技术更为简单、快速,且效果明显。它能明显地检查出IC掩模里的黑点、针孔、刻痕、电路缺损、短路和断路等微小缺陷,并可检测出最小线度为2μm的缺陷。     

汽车BCM的故障诊断设计及实现

本文针对BCM的负载控制功能设计了一种电流反馈电路及过载、短路、开路故障诊断方法,能够实时监测负载的工作电流,根据负载电流的变化情况及驱动方案选型,准确判断出是否发生过载故障、短路故障及开路故障,以正常启动或关断负载,不仅能够实现既定的负载控制功能,还能够在发生过载、短路故障时及时关断保护.     

微电子文摘

1 IC CAD/CAT/CAM技术WD93101 适用于容错单片集成电路的成品率统计模型=在设计容错结构超大规模集成电路时,为了选取最佳冗余形式,必须评估采用各种冗余方法的电路成品率。本文介绍了适用于具有冗余结构的VLSI的成品率统计模型。根据文中描述的模型,有一个广义的负二项式分布,而且这种分布取决于利用玻色-爱因斯坦统计学或麦克斯韦-玻耳兹曼统计学的碎屑缺陷尺寸。文章推导出了适合表征电路模型间的缺陷正规和非正规分布时不同冗余方法的电路成品率表达式。参7(下一)     

捕捉集成电路中多余物方法的研究

集成电路存在的多余物可以分为可动和不可动两个类别，揭示了多余物产生的来源以及确定多余物存在的3种方法。介绍了塑封、陶封、玻璃熔装电路的封装结构以及如何采用开盖法、开洞灌封法、中间开孔法这3种捕捉多余物的方法，并对各种方法的适用范围和使用的特点进行了分析。以陶封电路为例，演示了用中间开孔法捕获可动多余物的过程。     

两种保险丝熔断报警器

本文介绍两种保险丝熔断报警器,能在保险丝熔断时自动发出声、光报警信号,具有电路简单,无需调试等优点,适用于农村家庭和电工房.图1所示的熔断报警器用于交流电路中.图中当保险丝BX正常时,氖灯ND两端电压为零而不发光,光敏管GD因无光照射而截止,可视其为开路状态,IC音乐横块不被触发,电路处于无声静止状态.当BX熔断时,ND两端电压达到起辉电压而发光,GD基极受光照而导通,其等效电阻减小,可视为短路,IC第②脚被触发工作,使第③脚输出信号,压电陶瓷片HTD发出音乐蜂鸣声,完成报警功能.     

对水下目标的多普勒直接定位

应用基于多普勒频移变化率分析的直接定位法给出了利用单个LOFAR声纳浮标对水下匀速运动目标的定解公式,与已有的必须检测到达航路捷径点的时间和频率的旧方法相比,新方法基本可在除接近航路捷径点外的任意位置上实现实时探测,不仅能近实时的给出水下目标的运动参数,而且还能直接获得目标当前的坐标位置参数,而不再是仅仅得到航路捷径距...     

对通孔消失机理的研究以及相应的解决方案

通孔消失是困扰半导体生产的难点之一.它与产品的生产合格率息息相关,正因为如此这一问题一直摆在业界工程师面前.由于这一问题的成因较多,故在分析和解决问题上存在诸多困扰.本文实验并分析了多种通孔消失的实效模型,结合先进的缺陷测试手段对其给出了不同的解决方案.此外,对相应的光刻胶也进行了研究并将缺陷密度与光刻胶的分辨率相联系,通过研究发现较低的分辨率的光刻胶的缺陷密度也相应较低.     

对通孔消失机理的研究以及相应的解决方案

通孔消失是困扰半导体生产的难点之一.它与产品的生产合格率息息相关,正因为如此这一问题一直摆在业界工程师面前.由于这一问题的成因较多,故在分析和解决问题上存在诸多困扰.本文实验并分析了多种通孔消失的实效模型,结合先进的缺陷测试手段对其给出了不同的解决方案.此外,对相应的光刻胶也进行了研究并将缺陷密度与光刻胶的分辨率相联系,通过研究发现较低的分辨率的光刻胶的缺陷密度也相应较低.     

Disaster-survivable cloud-network mapping

Cloud-computing services are provided to consumers through a network of servers and network equipment. Cloud-network (CN) providers virtualize resources [e.g., virtual machine (VM) and virtual network (VN)] for efficient and secure resource allocation. Disasters are one of the worst threats for CNs as they can cause massive disruptions and CN disconnection. A disaster may also induce post-disaster correlated, cascading failures which can disconnect more CNs. Survivable virtual-network embedding (SVNE) approaches have been studied to protect VNs against single physical-link/-node and dual physical-link failures in communication infrastructure, but massive disruptions due to a disaster and their consequences can make SVNE approaches insufficient to guarantee cloud-computing survivability. In this work, we study the problem of survivable CN mapping from disaster. We consider risk assessment, VM backup location, and post-disaster survivability to reduce the risk of failure and probability of CN disconnection and the penalty paid by operators due to loss of capacity. We formulate the proposed approach as an integer linear program and study two scenarios: a natural disaster, e.g., earthquake and a human-made disaster, e.g., weapons-of-mass-destruction attack. Our illustrative examples show that our approach reduces the risk of CN disconnection and penalty up to 90 % compared with a baseline CN mapping approach and increases the CN survivability up to 100 % in both scenarios.     

基于改进VGG网络的单体热电池X光图像无损检测方法研究

为解决单体热电池生产中出现的安装错误、人工检测耗时耗力的问题,提出一个结合迁移学习和卷积 神 经网络(convolutional neural network,CNN) 的单体热电池缺陷检测模型。首先,对数据集图像进行裁剪、加噪等预处理,以VGG16(visual geometry group 16) 网络作为 模型的骨干架构,在瓶颈层后增添选择性核(selective kernel,SK) 卷积;然后,增添全局平均池化(global average pooling,GAP) 层, 增加Dropout层及添加 L2 正则化等微调操作,得到单体热电池缺陷检测模型Q-VGGNet;最后,在大型公开数据集ImageNet上进 行预训练学习,将获得的权重参数迁移到单体热电池图像识别模型Q-VGGNet上。测试实验表明:6种 网络模型对数据集缺陷图像的总体识别准确率分别达到了98.39%、94.44%、97.27%、96.34%、93.71%、 95.61%,Q-VGGNet网 络模型 对合格图像和 漏装负极、极耳断裂、漏装集流片3种缺陷图像 识别准确率 分别达到了99.6%,95.9%,99.6%和98.4%。检测结果表明:该方法能够更准确、快速地检测热电池缺陷, 拥有良好的缺陷诊断能力,较传统方法提高近3%,为人工检测单体热电池缺陷提供了良好的解决途径。     

基于聚类分析和骨架提取的含裂纹超声红外热像增强方法研究北大核心CSCD

超声红外热图像因噪声干扰及缺陷位置的热扩散,导致其存在对比度差、清晰度低、边缘模糊等问题。为了增强红外图像视觉效果,提高缺陷检测能力,提出了一种基于聚类分析和缺陷骨架的超声红外图像增强方法。采用基于kmeans的DBSCAN聚类算法对裂纹发热区域进行识别聚类,将图像分解为缺陷生热区域与非缺陷区域;然后,对缺陷区域进行骨架描述,并沿裂纹骨架走向采用改进的部分子块重叠直方图均衡算法对缺陷图像进行增强。提出的超声红外图像增强方法与常用的直方均衡化、限制对比度自适应直方图均衡化、自适应同态滤波三种方法进行对比,结果表明所提的增强方法可以得到对比度更显著的图像,具有明显的优势。提出的方法为增强超声红外图像视觉效果、提升裂纹诊断能力提供了一种有效方法。     

The effects of defects on the early failure of metal interconnects

A method that predicts the effect of particular defects on the failure rate of metal interconnections in semiconductor integrated circuits due to electromigration is presented. The defects of interest are missing material that reduces the effective cross section of the conductor at the point of the defect. Reliability measures for the conductor are computed from a given defect distribution. These defects appreciably increase conductor failure rate during early life but have little effect on median life for linewidths above 1 μm. However, for defect densities typically encountered in current semiconductor manufacturing environments a rapid decrease in median life is predicted for conductors less than 0.30 μm wide. This result extends the practical data for submicron conductors. Poorer median life as well as poorer yield due to these defects will ultimately limit the trend toward narrower linewidths unless a way is found to overcome this problem     

An efficient algorithm for locating soft and hard failures in WDM networks

Fault identification and location in optical networks is hampered by a multitude of factors: the redundancy and the lack of coordination (internetworking) of the managements at the different layers (WDM, SDH/SONET, ATM, IP); the large number of alarms a single failure can trigger; the difficulty in detecting some failures; and the resulting need to cope with missing or false alarms. Moreover, the problem of multiple fault location is NP-complete, so that the processing time may become an issue for large meshed optical networks. We propose an algorithm for locating multiple failures at the physical layer of a WDM network. They can be either hard failures, that is, unexpected events that suddenly interrupt the established channels; or soft failures, that is, events that progressively degrade the quality of transmission; or both, hard failures are detected at the WDM layer. Soft failures can sometimes be detected at the optical layer if proper testing equipment is deployed, but often require performance monitoring at a higher layer (SDH, ATM, or IP). Both types of failures, and both types of error monitoring, are incorporated in our algorithm, which is based on a classification and abstraction of the components of the optical layer and of the upper layer. Our algorithm does not rely on timestamps nor on failure probabilities, which are difficult to estimate and to use in practice. Moreover, our algorithm also handles missing and false alarms. The nonpolynomial computational complexity of the problem is pushed ahead into a precomputational phase, which is done off-line, when the optical channels are set up or cleared down. This results in fast on-line location of the failing components upon reception of the ringing alarms.     

Cutset Manipulations for Communication Network Reliability Estimation

The problem of calculating the reliability of a communication network of given topology is discussed. The definition of failure is generalized from simple disconnection to the event that terminal capacity falls below some threshold, and simple methods are developed for bounding the probability of such failures and for approximating the mean time between failures (MTBF). It is shown that the cumulative distribution function of terminal capacity is readily calculated, and that the dependence of network reliability on individual link reliability is substantially different when the generalized (and more realistic) definition of failure is used.