Optimal Scheduling of Complex Multi-Cluster Tools Based on Timed Resource-Oriented Petri Nets

Qinghua Zhu, Naiqi Wu, Yan Qiao, Mengchu Zhou

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Complex multi-cluster tools have been extensively used in semiconductor manufacturing. It is crucial to increase their productivity by their effective operation. With structural complexity, multiple robots, and the interaction among individual tools, it is very challenging to schedule a tree-like multi-cluster tool. This paper investigates the scheduling problem of such a tool whose bottleneck individual tool is process-bound. The system is modeled by well-known discrete-event models, i.e., resource-oriented Petri nets. Based on the models, for the first time, this work develops necessary and sufficient conditions under which a one-unit (wafer) periodic schedule exists and shows that an optimal one-unit periodic schedule can always be found. Algorithms with polynomial complexity are presented to find the optimal cycle time and the one-unit periodic schedule. Industrial examples are used to illustrate the proposed method, and they show that a significant reduction in cycle time can be obtained in comparison with the existing method.

Original languageEnglish (US)
Article number7445820
Pages (from-to)2096-2109
Number of pages14
JournalIEEE Access
StatePublished - 2016

All Science Journal Classification (ASJC) codes

  • General Computer Science
  • General Materials Science
  • General Engineering


  • Cluster tool
  • Petri net (PN)
  • multi-robot systems
  • scheduling
  • semiconductor manufacturing


Dive into the research topics of 'Optimal Scheduling of Complex Multi-Cluster Tools Based on Timed Resource-Oriented Petri Nets'. Together they form a unique fingerprint.

Cite this