The transition to 300mm wafer size introduced a lot of new technologies to wafer fabrication facilities that mandated the presence of intrabay automated material handling systems (AMHS) for moving wafer carriers between the stockers and production tools within a bay. The design of intrabay AMHS depends on the configuration and the mode of delivery. A generic reusable tool is developed for modeling and simulation of the 300mm intrabay AMHS different designs. The tool relies on a built-in database and a library containing the different components of intrabay AMHS and the different processing tools. The design of the generic tool guarantees its reusability for building different models of bays with virtually any design. The tool output includes a number of AMHS performance metrics that can be used effectively in comparing different designs of an intrabay AMHS.