Scheduling semiconductor wafer production: an expert system implementation

A flexible environment for the production of semiconductor wafers is described. This facility currently manufactures over 300 wafer products. Each product follows a different route through a series of discrete processing operations, more than 150 of which take place in the facility. An expert system approach to scheduling, which efficiently utilizes the processing equipment within each cell while meeting overall due dates of all wafer lots, is detailed. The results obtained with the expert system and its applicability are evaluated.<>