变频共电串扰对PCM测试的影响

Effect of Electrical Erosstalk Frequency in Parameter Control Monitor

PCM即Parameter Control Monitor(参数监控)的简称,是半导体制程工艺必备的最后一道工序,主要作用是通过电学参数测试的分析对在线工艺及产品的质量进行监控,以发现一些潜在或已发生的工艺或设备异常,为异常的分析和解决提供详细的参数信息,保证在线工艺和设备的稳定,为客户提供高品质的半导体产品。遵循摩尔定律的集成电路行业发展迅速,制造工艺越来越复杂,目前一般都需要上百道制作工序,必须要保证每道工序都处于受控状态,这给PCM测试带来了巨大的挑战和压力。随着芯片尺寸越来越小,测试用电压电流的精度要求很高,对PCM的自动测试系统来说,要求能监测到f A级别的漏电流,在实际应用过程中不可避免会遭遇一些困难,比如环境温湿度超标、接地不够良好、光照影响、环境洁净度差等都会引起测试的波动。主要讨论在测试过程中,共电串扰产生的测试异常及问题的解决过程。

Parameter Control Monitor （PCM）, the final necessary step of Semiconductor processing, is mainly used in monitoring the product quality by analyzing the electrical parameters during the processing, by which to find some potential or exiting equipment exception, providing detailed parameter information for the analysis and resolution of abnormal. It ensures the stability of online technology and equipment, and provides customers with high-quality semiconductor products. Following Moore＇s Law in IC industry, the fabrication processes have come more and more complex. Basically, there are hundreds steps in the production process. Thus, to make ensure each process in a controlled state, it brings great challenges and pressures in PCM test. With decreasing the chip size, the testing accuracy of the voltage and current has become higher than previous ones. To the automatic PCM test systems, the accuracy needs to be up to fA. Nonetheless, it＇s need to point out that it will inevitably encounter some difficulties in the practical application, such as ambient temperature, exceeded humidity, the ground is not enough good, light impact, environmental cleanliness and poor, which further leads to the fluctuations of the test. In this work, we will demonstrate the different phenomenon of abnormal electrical crosstalk test during the rest process and show how to solve it.