Application of a constraint based production line management system for semiconductor manufacturing

One of the key components of the theory of constraints is the application of the "drum-buffer-rope" principle to production line management. This involves linking the start of material into the production line with the performance of the constraint. The methodology presented in this paper uses an inventory profile system (IFS) automation tool to track the factory inventory and performance of constraint and near constraint equipment. This equipment is monitored using control charts of the inventory. A wafer start modulation algorithm computes the over or under inventory in wafers and the recovery time which are used in the starts decision making process.