Abstract
Control chart has been widely implemented in manufacturing for quality management, and its purpose is to monitor the product quality during the manufacturing process. However, caused by key-factors’ variation, Control-chart, collected from actual production process, will appear with special characteristics. Thus, if could identify and improve these key-factors, hidden to contribute the abnormal Control chart, on time, product quality could be improved. Firstly, the differentiation of quality control system between Conventional and LTPS-TFT-LCD industries is discussed; through the discussion, macro quality concept is built. Next, aiming at lithography process, most critical in LTPS-TFT-LCD manufacturing, adopt Ishikawa Diagram to analyze the defect-cause(s), and provide the analysis information for Control chart. Finally, through the real practical case study, the research concentrates on analyzing six abnormal modes in control chart, finding out the critical factors and further discussing the related question.