A simulation study on release, synchronization, and dispatching in MEMS fabrication

MEMS (microelectromechanical system) fabrication can be organized as three sub-processes, that is, the front-end process, the wafer cap process, and the back-end process. The coordination between the releases of raw wafers to the two parallel sub-processes, the front-end process, and the wafer cap process, is always an important issue. Previous research work has developed synchronization rules to create effective coordination. In this paper, new synchronization rules and dispatching rules are developed and they are evaluated with more release rules. From this much more extensive simulation experiment, it is found that there are significant two-factor and three-factor interactions among these three types of rules and we have to consider them all together in order to achieve the best performance for the MEMS fabrication system. Moreover, the complicated relationship between the performances (cycle time and total work-in-process) is also indicated.