Proceedings of the 1999 Winter Simulation Conference P. A. Farrington, H. B. Nembhard, D. T. Sturrock, and G. W. Evans, eds. APPLICATION OF SIMULATION AND THE BOEHM SPIRAL MODEL TO 300-MM LOGISTICS SYSTEM RISK REDUCTION Jerry Weckman Theron Colvin PRI Automation Automation Planning and Design 1250 S. Clearview Ave. Mesa, Arizona 85208, U.S.A Robert J. Gaskins PRI Automation 805 Middlesex Turnpike Billerica, Massachusetts 01821-3986, U.S.A. Gerald T. Mackulak Industrial Engineering Arizona State University Tempe, Arizona 85287-5906, U.S.A. ABSTRACT Building on the lessons learned from the 150-mm-to 200- mm transition in semiconductor manufacturing, much work has gone into the planning and development of 300-mm fabs. Examples of this include the work produced by SEMI, International SEMATECH’s I300I and Japan’s J300 programs. This work includes various standards and guidelines regarding the architecture and interfaces of loadports, equipment and software components. However, despite these efforts, there are a number of significant 300-mm risks that remain. Some of these risks involve specific fab operational methodologies, which may vary depending upon the type of fab involved. Additionally, there are many other risks associated with the development and implementation of a robust 300-mm logistics system. The purpose of this paper is to: • Define some of the key risks associated with the development and implementation of a fully integrated 300-mm logistics system. • Show how simulation can be used in conjunction with a risk management approach, i.e. Boehm spiral model, to play a key role in the mitigation of those risks. 1 INTRODUCTION In 1997, the semiconductor industry responded with several key international cooperation programs as a number of companies began planning 300mm fabs. In 1998, many of these new fab plans were put on hold. Not only was the 300mm equipment not viewed as production ready, but end users were concerned about the level of risk associated with the integration of a number of legacy automated material handling, manufacturing execution, and material control software systems that would be needed to manage the fab’s logistics (integrated production and material movement). The primary objective of this paper is to clearly detail how discrete-event simulation can play a key role in ensuring the successful development and implementation of 300mm logistics systems. This will be accomplished by pointing out some of the current risks and challenges associated with 300mm logistic system development. Then a risk reduction approach based on the Boehm spiral (1988) model will be described. Finally, the way in which simulation becomes instrumental in reducing 300mm logistics development risks using this approach will be illustrated. 2 300-mm LOGISTICS SYSTEM RISKS There are a number of risks that must be fully comprehended and addressed before a logistics system can be successfully implemented within a fab. 2.1 Software Risks One of these risks involves developing a fully integrated material logistics system where the manufacturing execution system (MES), material control system (MCS), and the automated material handling system (AMHS) and other production system software work in a closely integrated arrangement. Previous factory control systems were designed around a Human-Centric philosophy, where they were interfaced with the automation systems that followed. The assumption was that operators would make decisions concerning scheduling, changes to schedules and material movement. A Schroeder (1997) Automation- Centric philosophy must now be adapted to develop the integrated controls system with fully automated (both interbay and intrabay) material movement systems. 912