This proposal addresses the technical challenge to U.S. industry for development of control systems that are adaptable to changes in the complex multiple, concurrent processes of a semiconductor manufacturing environment. The proposed work is exploratory research which will result in the development of an abstract setting for the control systems, involving a three tier hierarchical approach, with each tier based upon a distinct control methodology. Progressing outwards toward the system operator, these tiers will be based on traditional PID and process control, adaptive control systems and control for discrete event systems. Consideration will be given to the incorporation of expert systems, embedded process simulators and neural networks. The abstract setting will provide a means of analyzing an designing control systems for the complex semiconductor manufacturing environment. Anticipated benefits/potential commercial applications - advanced control systems for the semiconductor manufacturing environment can be considered an enabling technology that offers significant potential for productivity improvement. There are over 350 wafer fabrication sites in the u.s. where advanced controls technology insertion could result in improved yields, throughput, quality, cycle times and process flexibility.
