This paper proposes the Discrete Event System Specifications (DEVS)-based simulation framework to model and simulate OHT system for 300mm Fab AMHS. Firstly, functional requirements for the OHT system in 300mm Fab AMHS are extracted from the previous studies in the operation of Fab AMHS and OHT system. Secondly, DEVS models and data structures for the OHT system are defined with the functional requirements. Thirdly, alternatives and issues while modeling OHT system with JR-net in VFS are discussed in this paper. Then, we propose modeling methods and theses issues in DEVS-based simulation architecture. Finally, this paper depict an implemented prototype of the proposed simulation framework which verifies its validity.
