An operator staffing and assignment model for foundry fabs

Abstract

This paper presents a linear programming (LP) model for simultaneously solving an operator staffing problem in a semiconductor fab. The problem is to determine the staffing level and assign operators to the staffing positions. The semiconductor fab has the following characteristics: it imposes a no-lay-off policy, but allows overtime; keeps high-quality shop floor operations; aims to control tightly the staffing costs; and faces frequent changes of product mix. The operator staffing problem in such a fab was not addressed in previous literature. The proposed LP model aims to minimize the operator staffing cost. The LP solutions have been examined and were found to be insensitive to stochastic demands modeled by various simulation replicates.