Simulation based planning and scheduling system for TFT-LCD Fab

In a typical LCD factory, a large number of product types are produced concurrently, 24 hours a day and 365 days a year, and there exist various constraints and re-entrant flows in the manufacturing processes. As a result, efficient planning and scheduling of LCD production is a big challenge. Presented in this paper is a simulation-based DPS (daily planning & scheduling) system that was developed by the authors and is being used in a modern LCD Fab in Korea. Also presented in the paper are a business architecture of LCD production management, internal structure of the DPS system, and Fab scheduling logic. The DPS system was installed at a large-size LCD Fab in 2006, and the system has been successfully used for two years leading to a considerable increase in on-time production of LCD panels and a sharp decrease in turn-around time.