A Generic Framework for Inter-Cell Control of a Semiconductor Manufacturing Facility

Abstract: Whenever the fabrication process consists of several steps and the dynamic modification of individual steps or step sequences of the process is allowed, inter-cell feedback and feedforward control can both be utilized to improve the quality of the fabrication process. Indeed, feedback and feed-forward control have been identified as important features of the semiconductor manufacturing facility of the future. However, the issue of providing enabling mechanisms for inter-cell control has not been adequately addressed. To fill this gap, we propose a novel design of a generic, adaptable and re-usable software enabler for inter-cell control in manufacturing facilities. This inter-cell controller is realized using active database technology. Active database systems, a recently emerging technology, can automatically carry out rule actions when designated events occur and corresponding conditions become true. For carrying out inter-cell control, the conditions of active database rules can be defined to check for scenarios in which inter-cell control can be utilized to improve the fabrication process. When the conditions for inter-cell control hold, firing of the associated rules causes appropriate actions to be taken to compensate for the errors in processing. The defined rule mechanism, which allows expression of the complete range of conditions for inter-cell control, provides for a generic and adaptable implementation of this type of control. With respect to system integration, the controller is being developed so that it can be integrated into existing manufacturing systems with minimal modification to existing components.