Simulation-based Assessment of Batching Strategies in a Multi-product Semiconductor Wafer Fabrication Facility
نویسنده
چکیده
In this paper, we present the results of a simulation study for the performance evaluation of certain batching strategies in a multi-product semiconductor wafer fabrication facility (waferfab). Batching in waferfabs means that we can process different lots at the same time on the same machine. As opposite to common scheduling and dispatching decisions in manufacturing beside assignment and sequencing decisions we have to make decisions on the content of a batch. Batching decisions have a large impact on the performance of a waferfab because of very long processing times of batching operations. We extend previous work on the evaluation of batching strategies from the two product-case to the case of a larger number of products and different product mix scenarios. We investigate three different batching heuristics. Our heuristics are based on the Apparent Tardiness Cost dispatching rule. Two of the suggested batching strategies take future lot arrival information into account. It turns out that the usage of future lot information is advantageous in many situations. We use a reference model of a waferfab of medium size in order to carry out the simulation experiments.
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