An algorithm to visualize tool difference transitions in semiconductor fabrications

To solve tool difference problems in semiconductor fabrication, it is necessary to identify problematic tool from numbers of process tools and process steps, and discover the cause of its performance difference. In this paper we propose a method to assist engineers in finding cause of tool difference. This method visualizes tool difference transition by post-processing results of periodically executed regression analysis. Effectiveness of this method is shown by Monte Carlo simulation based on a conceptual model of a fabrication line.