A TOC combining ACO sequencing method for the semiconductor manufacturing fabrication

Based on the analysis on the scheduling characteristics of the semiconductor manufacturing fabrication lines, we propose a TOC(Theory-of-Constraints) combining ACO(Ant Colony Optimization) sequencing method. The method firstly determines the bottlenecks of a semiconductor manufacturing fabrication line, and then applies an ACO algorithm to obtain the optimized jobs processing priority sequence of the bottlenecks, which is the constraint to deduce the jobs processing priority sequence of other non-bottleneck areas. A simplified semiconductor wafer fabrication line model(Mini-fab) is used to verify and validate the proposed method. The simulation results show that the proposed method is superior to the common scheduling rules (such as FIFO, EDD and CR), with the ability to obtain an optimized scheduling solution in a reasonable time.