In-line defect sampling methodology in yield management: an integrated framework

Abstract

In this paper we provide an integrated framework for designing the optimal defect sampling strategy for wafer inspection, which is crucial in yield management of state-of-the-art technologies. We present a comprehensive cost-based methodology which allows us to achieve the trade-off between the cost of inspection and the cost of yield impact of the undetected defects. We illustrate the effectiveness of our methodology using data from several leading fablines across the world. We demonstrate that this work has already caused a significant change in the sampling practices in these fablines especially in the area of defect data preprocessing (declustering), in-line defect based yield prediction, and optimization of wafer inspection equipment allocation.