A Mini-FAB simulation model comparing FIFO and MIVP(R) schedule policies (outer loop), and PID and H/sup /spl infin// machine controllers (inner loop) for semiconductor diffusion bay maintenance

This Multiscale Integration of Manufacturing and Assembly Processes (MIMAP) demonstration project investigates the integration of two or more Thrust Area Groups (TAGs) by creating a flow of information and processes from two areas of research. The control theory research of two different controllers for diffusion furnaces used in semiconductor manufacturing which predict a specific window of machine failure, the mean-time-before-failure (MTBF). The objective is to increase yield, decrease cycle time, work-in-progress (WIP) and production costs. A global factory Minimum Inventory Variability Scheduling policy (MIVP(R)), used to decrease cycle time and cycle time variance when compared to a first-in-first-out (FIFO) scheduling policy, was used to make the comparisons between the two inner and outer loop controllers. The project's Cross Cutting Methodologies (CCMs) is ensured by the participation of faculty from three different colleges (LAS, CEAS, and CTAS) and two electrical engineering doctoral students.