Heuristics for minimizing makespan on parallel dedicated machines with family setups

Abstract

This paper develops the heuristics for scheduling in a semiconductor wafer fabrication facility (fab) with machine dedication characteristic. Machine dedication in a fab is the characteristic that each machine can process only a set of specific product families. A setup operation is required between processings of wafer lots of different product families, and the length of the setup time is significantly long compared with processing times of wafer lots. This scheduling problem can be found at the etching, chemical vapor deposition and ion implant processing workstations. For the objective of minimizing makespan, we develop several heuristic algorithms. To evaluate performance of the suggested algorithms, a series of computational experiments are performed on a number of test problems and results show that the suggested algorithms give good solutions in a short amount of computation time.