Scheduling method for single-arm cluster tools of wafer fabrications with residency and continuous reentrancy

In order to enhance the utilization of single-arm cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic scheduling algorithm is presented. A nonlinear programming scheduling model is built on the basis of bounding the scheduling problem domain. A feasible path search scheduling method of single-arm robotic operations is put forward with the objective of minimal makespan. Finally, simulation experiments are designed to analyze the scheduling algorithms. Results indicate that the proposed algorithm is feasible and valid to solve the scheduling problems of multiple wafer types and single-arm clusters with the conflicts and deadlocks generated by residency time and continuous reentrancy constraints. © Copy Right.