Modeling and analysis of semiconductor manufacturing plants using time Petri net models: COT business case study

The radical change in the economical situation affected the semiconductor manufacturing business. Recently COT (customer oriented technology a.k.a. IC foundry) business is gaining popularity in many semiconductor manufacturing companies. In this field of semiconductor manufacturing business, predicting and controlling the fabrication cycle time, work in process status and in-line data with maintaining the high yields and quality of the products are the most important factors in the success of the whole business. Although semiconductor fabrication, excluding the design and assembly stages where these two stages are optional in COT business, is process oriented, just like the FMS in traditional assembly oriented manufacturing system, flexibility plays a major role. In this paper, the authors model and analyze the COT semiconductor fabrication from the customer order to the delivery stage using time Petri net models. Then a method to obtain turn around time, work in process status and capacity on-line by analyzing the behavior of the model is proposed by the authors.