A Fuzzy Scheduling System for Dedicated Machine Constraint

Abstract

In this paper, we propose the Fuzzy Scheduling System (FSS) to deal with the dedicated machine constraint. The constraint of having a dedicated machine for photolithography process is the new issue introduced in photolithography machinery due to natural bias. If we randomly schedule the wafer lots to arbitrary photolithography machines at the first photolithography stage, then the load of all photolithography machines might become unbalanced. It is the main contributor to the complexity and uncertainty of the semiconductor factory. The FSS is to select the best photolithograph machines for each wafer lot at the first, unconstrained, stage to tackle this dedicated machine constraint and to maintain the load balancing among photolithography machines.