A new formulation technique for alternative material planning—an approach for semiconductor bin allocation planning

This paper presents a new formulation technique for using Linear Programming (LP) to solve the alternative material planning problems. This new formulation technique called the acceptable material set generation procedure is an extension of a similar technique for formulating the alternative machine capacitated planning problem—the capacity set generation procedure, proposed originally by Leachman and Carmon [IIE Transactions, 24, 62–72 (1992)]. A typical practical application of the alternative material planning technique is the bin allocation planning problem for semiconductor manufacturing. The LP formulation of the semiconductor production planning problem is generally large. However, based on a bin allocation planning case study, we find that our technique not only completely eliminates allocation variables, but also saves about one-third of the constraints of the conventional one. Thus, this new technique reduces the size of the LP for bin allocation planning in semiconductor manufacturing and saves considerable computer time and storage space. In Network Theory terminology, this paper suggests a new way of formulating transportation problems or transshipment problems without using flow variables. Due to the elimination of flow variables and solving the dual problem of the LP by the new formulation technique, if the number of variables of the LP is less than the number of constraints, the computation time could be considerably reduced.