Implementation of a Fluctuation Smoothing Production Control Policy in IBM´s 200mm Wafer Fab

Efficient operation of IBM Vermont’s 200mm semiconductor wafer fabrication facility is essential to achieve the objective of transforming the site into a world class foundry manufacturer. To that end, we develop a fluctuation smoothing for the variation of cycle time (FSVCT) production control policy capable of allowing for a diversity of cycle time commitments. The policy directs which lot should next receive processing when a tool becomes available. In the absence of a validated cycle time model for the fabricator, we obtain estimates of achievable cycle time performance in the presence of business constraints on the cycle times of certain lots via a consequence of Little’s law. The mean and variation of cycle time implications for IBM Vermont’s facility are highlighted.