Physics Based Research Of IC Failure Rate Prediction Method

With the continuous development and popularity of semiconductor technology, the integrated circuit market was gradually expanded from the past high reliability territory, such as military or space field, to the broader commercial and civil markets. Reliability simulation and predicting tools, becomes a powerful approach to speed up the development programs, and to reach the balance between product performance and reliability.Since the long update cycle and limit of applied range, the traditional method of "reliability manual" is more and more difficult to keep up with the pace of the semiconductor industry development. So, the method based on reliability physics is expected to replace the traditional method gradually. In the past, reliability physical model is for short in terms of failure distribution and failure rate, and this article would give some research on this aspect.Based on the life model, through the monte-carlo method and other mathematical methods, Matlab simulations were applied to get the failure distribution of three failure mechanisms of integrated circuit, such as HCI, NBTI and EM. By comprehensive understanding of percolating model, we get TDDB failure distribution model. Parameters of these distribution models are comes from the characteristics of the device and the environment. Thus we established the relationship between the failure distribution of four failure mechanisms and the device intrinsic parameters, and make it possible to predict the failure rate of integrated circuits based on failure physics.Integrated circuit is composed of a large number of MOS devices, and a various of failure mechanism will cause device failure in a so-called competing failure modes. This paper also discusses the failure distribution of the total integrated circuit and the calculation of the constant failure rate.Based on the calculation process of the failure rate, a software tool has been programmed by VB. By utilize this software, when a user input the parameters of the IC and of the environment, then the software will calculate the failure rate and failure distribution accordingly.