Multiobjective Scheduling in Semiconductor Manufacturing Systems
Date Issued
2008
Date
2008
Author(s)
Chiang, Tsung-Che
Abstract
In this dissertation, we address the scheduling problem in the semiconductor manufacturing industry, one of the most complicated and capital-intensive industries in the world. Due date delivery performance is of our particular concern to cater to the make-to-order market environment nowadays. We propose a real-time scheduling approach to resolve the main decisions including serial dispatching and batch dispatching. The real-time scheduling approach is based on two newly proposed dispatching rules, whose features include total urgency estimation and due date extension. To apply the dispatching rules, the weakness of traditional paradigm is discussed, and a 2-D assignment-based paradigm is proposed. In addition, a performance optimizer based on the evolutionary algorithm is developed with the consideration of multiple objectives simultaneously. The critical components of the multiobjective evolutionary algorithm (MOEA) including fitness assignment, mating selection, environmental selection, and local search procedure are designed elaborately to balance between exploration and exploitation. By using the proposed MOEA-based optimizer, it is easy for production managers to obtain a set of rules and parameter values which is fit to their own manufacturing systems and is able to produce schedules to their satisfaction. Experiments are conducted on a representative test bed consisting of seven wafer fabrication facilities under different levels of fab load and due date tightness. Considering performance measures including on-time delivery rate, mean tardiness, and maximum tardiness simultaneously, the proposed serial and batch dispatching rules significantly outperform 16 existing serial rules and 6 batch rules, respectively. The proposed MOEA also shows superiority over a representative approach in the literature. According to these promising results, we can conclude that the proposed real-time scheduler and performance optimizer are useful tools to do multiobjective scheduling in the semiconductor manufacturing industry.
Subjects
semiconductor manufacturing
scheduling
dispatching
batch
multiobjective
evolutionary algorithms
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-97-D90922009-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):ac7d3fef04814f7fc62ce75b08888d74