A new deadlock prevention policy for multi-cluster tools with dual path

Multi-cluster tools are widely used for semiconductor silicon wafer production. The multi-cluster tools system consists of two or more cluster tools connected with buffer or process modules. Deadlocks are frequently caused in the multi-cluster tools by the restriction of transfer modules and limited number of available spaces. In this paper, we propose a novel deadlock prevention policy for multi-cluster tools. A timed Petri net model for multi-cluster tools is developed. A new deadlock prevention policy is proposed. The proposed deadlock prevention policy is applied to dual-armed multi-cluster tool with dual path. The deadlock-freeness is confirmed by deriving empty siphons for the Petri net model. The computational results show that the performance of scheduling with the proposed deadlock prevention policy is better than the conventional deadlock prevention policy.