Integration of capacity planning techniques for tool portfolio planning in semiconductor manufacturing

Because semiconductor wafer manufacturing plants are large manufacturing systems with complex queuing behavior, sophisticated techniques are required for capacity planning. Static capacity modeling, queuing capacity modeling, and simulation are three common methods of capacity analysis, but they have different premises and provide capacity information in different granularity levels. This paper presents a planning procedure that integrates the three methods of capacity analysis for resource portfolio planning in semiconductor manufacturing and novel modeling techniques of each method are described. First, the accuracy of static capacity analysis is improved by predictive estimation of batch machine efficiency. Second, queuing analysis is utilized to generate the solution space of resource portfolios. Third, simulation techniques for the determination of the steady state and the reduction of simulation time are described. Finally, this paper also includes an analysis of the soundness of the integrated procedure and the compatibility of models. Using the proposed methodology can significantly speed up the cycle time of capacity planning in semiconductor manufacturing. Because a large number of alternative portfolios can be generated and evaluated with multiple performance criteria, portfolio optimization is also greatly facilitated.