Abstract
This research uses a case study methodology to investigate ways of improving the outgoing quality assurance (OQA) processes of a 12-inch wafer foundry. It applies the value stream mapping method of lean production to analyse the wafer OQA processes. The study ensures that all outgoing wafers satisfy customers’ requirements without waste. In this paper, a current state map is used to locate potential waste and problematic process flows. Meanwhile, system simulation is adopted to construct the automatic material handling system and the equipment, transportation, and dispatching automation production module for the OQA processes—namely, the To-Be model and the future state map. The empirical results show that, for the To-Be model, the total lots of three customers per month increased from 3,106 to 3,719 pieces—about a 20% increase—and that the average product cycle time for customers A, B, and C dropped by 43.67%, 57.91%, and 58.39%, respectively. Furthermore, the operators’ utilisation rate increased from 61% of 10 operators on the day and night shifts to 87.26% of seven operators on the day and night shifts—about a 30% decrease of labour costs. Therefore, this study applies lean production (removing the non-value-added activities) and automation to improve the case company’s wafer OQA processes.
Additional information
Notes on contributors
JrJung Lyu
JrJung Lyu is a professor in the Department of Industrial and Information Management at National Cheng Kung University, Taiwan, ROC. He obtained a PhD degree in the Department of Industrial Engineering from the University of Iowa, USA. He has participated in many projects, public services and reviewing committees. Dr. Lyu has published over 80 journal papers and earned the National Quality Award in 2002. He has worked on research projects in the areas of new product development, collaborative design, and supply chain management.
Ping-Shun Chen
Ping-Shun Chen is a professor in the Department of Industrial and Systems Engineering at Chung Yuan Christian University, Taiwan, ROC. He obtained a PhD degree in the Department of Industrial and Systems Engineering from the Texas A&M University, USA. His research area focuses on supply chain management, system simulation, and healthcare simulation applications.
Wen-Tso Huang
Wen-Tso Huang is an associate professor at the Business School in Minnan Normal University, China. He holds a PhD in Industrial Engineering and Management from National Chiao Tung University, Taiwan, ROC. He taught operations courses at the undergraduate level. He has many publications in prestigious journals such as International Journal of Production Research, Journal of Biomedical Informatics, Communications in Statistics–Theory and Methods.