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本文论述了寻找缺陷源的工作，缺陷会导致硅片上的管芯失效。要做这一工作，必须能够在线确定缺陷的类型和密度，以确定缺陷是在工艺中的哪几步产生的。通常有两种方法：一种是用显微镜对产品或测试片进行检查（镜检）；第二种是使用电测试结构的短流程试验。在作VLSI技术的工程分析时，这两种方法都有明显的局限性。镜检的数据缺乏可重复性，并且，不同操作者的结果有很大差别。此外，在当前的半导体技术中，缺陷尺寸与线宽相接近，使得镜检的灵敏度降到很低的水平。电测试结构需要一层经光刻和腐蚀的导电薄膜，要用间接的方法才能得到高分辨率的缺陷截面，这大大限制了试验过程的选择余地。由于上述方法的限制，减少缺陷的工作是困难而费时的，并由于很难验明缺陷源而导致器件失效。用KLA－2020自动硅片检查系统进行自动缺陷检查，解决了这些问题，极大地提高了效率和成功率。本文把自动缺陷检查与镜检及基于电测试结构的短流程试验进行了比较，讨论了其性能。同时，以一个实际应用为例子，描述了用自动缺陷检查减少缺陷的方法，这个方法包括标准问题求解法和用来分离并解决主要缺陷结构的试验设计技术。这个例子描述了一系列短流程试验，这些试验使用KLA-2020产生的数据，逐渐缩小有问题工艺的区域，
This article addresses the job of finding sources of defects that can void the die on silicon. To do this, you must be able to determine the type and density of defects online to determine where the defects occurred during the process. There are usually two ways: one is to inspect the product or the test piece with a microscope (microscopy); the second is a short-run test to use the electrical test structure. Both of these methods have obvious limitations when doing engineering analysis of VLSI technology. Microscopy data lack of repeatability, and, the results of different operators are very different. In addition, in the current semiconductor technology, the defect size is close to the line width, so that the sensitivity of the microscopic examination is reduced to a very low level. The electrical test structure requires a layer of conductive film that has been lithographed and etched to obtain a high-resolution defect cross-section with an indirect method, which greatly limits the choice of test process. Due to the limitations of the above method, the work of reducing the defects is difficult and time-consuming, and the devices fail due to the difficulty in identifying the source of the defects. Automated defect inspection with the KLA-2020 automated wafer inspection system addresses these issues and dramatically increases efficiency and success rates. In this paper, automatic defect inspection and microscopy and electrical test structure based on the short-flow test were compared and discussed its performance. In the meantime, a practical application is described as an example of a method of reducing defects by automatic defect inspection. This method includes a standard problem solving method and experimental design techniques for separating and solving the major defect structures. This example describes a series of short-flow tests that use data generated by KLA-2020 to gradually reduce the area of the problematic process,