A state-of-the-art automation system of an ASIC wafer fab in Japan

In the implementation of computer integrated manufacturing (CIM), there are varying degrees of integration. Within the semiconductor wafer manufacturing industry, only a few companies have installed a comprehensive and fully automated CIM system in their facilities. Thus, compared to other industries, wafer fabs continue to require significant numbers of production personnel. This makes work-in-process (WIP) control and yield problems more complex and difficult. This paper describes the key points of a state-of-the-art automation system, called FABCON, that was developed and is being implemented in an ASIC wafer fabrication facility (fab) in Japan. This system was created through the collaboration of both Japanese and American companies. Along with the traditional CIM functions of automatic lot tracking, recipe setting, and process data collection, this system also creates the production schedule automatically, and controls the transport of almost all wafer carriers throughout the fab by robots. Specifically, this paper discusses a distributed fab control system based on ISA standard 386 and 486 based PC´s, a dynamic shop floor scheduler/dispatcher, wafer carrier transportation robotics, feedback/feedforward process control, and standardization of equipment interfaces. In addition, this paper describes some of the experiences in the course of development and implementation of the system.