A HEURISTIC SCHEDULING APPROACH TO THE DEDICATED MACHINE CONSTRAINT

摘要

The constraint of having a dedicated machine for the photolithography process in semiconductor manufacturing is a new challenge introduced in photolithography machinery due to natural bias. With dedicated machine constraint, the wafer lots passing through each photolithography process have to be processed by the same machine. The purpose of the limitation is to prevent the natural bias of the photolithography machine. However, much research proposed by previous researchers did not discuss the dedicated photolithography machine constraint. In this paper, we propose the Load Balancing (LB) scheduling approach based on a Resource Schedule and Execution Matrix (RSEM) framework to tackle the constraint. The proposed LB approach schedules each wafer lot at the first photolithography stage to a suitable machine according to the load factor of these photolithography machines. We describe the LB approach and the construction process of the RSEM framework. We also present an example to demonstrate our approach and simulation results to validate our approach.