Signature Analysis: Simulation of Inventory, Cycle Time, and Throughput Trade-Offs in Wafer Fabrication

Signature analysis provides a powerful heuristic method for the planning of simulation experiments and for the interpretation of simulation results. Signature analysis has been developed within the context of simulation of the dynamics of wafer fabrication operations in integrated circuit manufacturing. Graphical display of cycle time, throughput, and inventory provides a "signature" of the dynamic behavior of a given operation. Signatures of manufacturing operations are used to address several management issues. The effects of unplanned equipment failures are shown. The variation of signatures with initial inventory and with different time frames for management decisions is illustrated. The extension of signature analysis to other simulations is indicated.