Application of Autosched AP Simulation Model in Wafer Fab

Wafer fabrication or "fab" simulation models are often used to assist the daily running of wafer production. Their main uses have been focused on testing production scenarios, to estimate cycle times, quote delivery times to customers, or test operational policies such as lot dispatching rules and material handling systems scheduling policies. Fab technologies sometimes stay in demand for as little as one year, after that wafer prices often drop rapidly. Based on this, many semiconductor manufacturers regard cycle time as the most important element and treat it as a monitored performance measure in wafer fabrication. One of the significant benefits of simulation modeling is the ability to conduct sensitivity ("What-If") analyses that allow us to experiment without disrupting the actual manufacturing operation. This paper will focus on and present the applications of the Autosched AP simulation software from Brooks Automation to provide ("What-IP\´) analysis and a characteristic curve relating Cycle time to Fab Utilization. The paper will show how simulation is used as a modeling tool to assist a production manager\´s decision-making process in production planning and effectively evaluate the factory\´s performance capabilities. Analysis will describe the impact of different percentage of factory loading on the cycle time.