Hotelling T2 Control Chart for Defects in IC Fabrication using Cluster Index

• Main Authors: Chih Li Huang, 黃志力
• Other Authors: Lee-Ing Tong
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/99929680432663330493

碩士 === 國立交通大學 === 工業工程與管理系 === 89 === For the integrated circuits (IC) manufacturer, the clustering of defects on a wafer due to the complicated manufacturing process becomes more evident with increased wafer size. The defect clustering phenomenon causes the Possion based c-chart invalid. Many modified control charts has been developed to reduce the false alarms caused by defect clustering problem. However, there are still some actions in employing these control charts. This study proposed a statistical process control method for monitoring wafer defect with clustering phenomenon. The method employs Hotelling T2 control chart using the combination of defect counts and cluster index as a modified measurement index for wafer defect with clustering. A case study is also presented, the results indicate that the proposed method is more effective than that of previous studies.