Scheduling in semiconductor wafer fabrication facilities producing multiple product types with distinct due dates

Abstract

It is important and necessary to meet customers`` orders in order to survive in competitive business environments. This is also true in the semiconductor industry such as manufacturing systems producing application-specific integrated circuit (ASIC) chips, which have the low-volume, high-variety characteristics. This paper focuses on scheduling of jobs in workstations in a semiconductor wafer fab producing multiple-type products that have different due dates and different process flows. The objective is to minimize the total tardiness of orders for wafers. In this paper, we suggest rules for batch scheduling in batch processing workstations and lot scheduling in serial processing workstations. Several new rules are developed by using the system-wide information such as the WIP level and the processing times at upstream and downstream workstations of workstations. Simulation experiments are carried out to compare new rules with previous rules. Results showed that new rules worked better than previous rules.