Scheduling of multicluster tools has received much attention due to its complexity of interaction among cluster tools. A cluster tool comprises several modules such as processing modules, a transfer module with a single or dual-armed handling robot, and loadlock modules. A multicluster tool comprises two, three, or more cluster tools that are interconnected with each other. In this paper, we propose a deadlock prevention policy for noncyclic scheduling of dual-armed multicluster tools. The proposed deadlock prevention policy is effective for generating an efficient schedule for two or three-connected multicluster tools with a single or a dual-path flow. This is proven by analyzing the strict minimal siphon of the Petri net model. The performance of the proposed method is compared with that of a maximal permissible deadlock prevention policy. The results demonstrate that the proposed method is computationally efficient for larger state spaces and more suitable than conventional deadlock prevention policies for generating effective schedules for noncyclic scheduling of multicluster tools. Note to Practitioners-Scheduling of multicluster tools has recently attracted attention in the growing semiconductor manufacturing industry. Most conventional studies on multicluster tools focus on cyclic scheduling to minimize cycle time with swap strategy. The challenge addressed by this paper is to derive a deadlock-free schedule for multicluster tools with noncyclic operations. We propose a simple deadlock prevention policy that can be applied to large-scale timed Petri net (PN) model of general multicluster tools without enumeration of siphon computations or solution of mixed integer programming. A timed PN model is developed for noncyclic operations of dual-armed multicluster tools with a dual ath. The computational results show that the approximately 10% of the total throughput of the proposed method is better than those of the conventional methods. It enables more efficient operations for noncyclic scheduling under transient periods including cleaning operations.

中文翻译：

---

多集群工具非循环调度的高效死锁预防策略


多集群工具的调度由于集群工具之间交互的复杂性而受到广泛关注。集群工具包括多个模块，例如处理模块、带有单臂或双臂搬运机器人的传输模块以及加载锁模块。多集群工具包括两个、三个或更多彼此互连的集群工具。在本文中，我们提出了一种用于双臂多集群工具的非循环调度的死锁预防策略。所提出的死锁预防策略对于为具有单路径或双路径流的两个或三个连接的多集群工具生成有效的调度是有效的。这通过分析Petri网模型的严格最小虹吸管得到证明。将所提出方法的性能与最大允许死锁预防策略的性能进行了比较。结果表明，所提出的方法对于较大的状态空间具有计算效率，并且比传统的死锁预防策略更适合为多集群工具的非循环调度生成有效的调度。从业者须知——多集群工具的调度最近引起了不断发展的半导体制造业的关注。大多数关于多集群工具的传统研究都集中在循环调度上，以通过交换策略最小化循环时间。本文解决的挑战是为具有非循环操作的多集群工具导出无死锁调度。我们提出了一种简单的死锁预防策略，可以应用于通用多集群工具的大规模定时 Petri 网（PN）模型，而无需枚举虹吸计算或混合整数规划的解决方案。 定时 PN 模型是为具有双 ath 的双臂多集群工具的非循环操作而开发的。计算结果表明，该方法的总吞吐量比传统方法提高了大约10%。它可以在瞬态期间实现更高效的非循环调度操作，包括清理操作。