Abstract:
The objective of this research is to summarize quality cost report to management and reduce the quality cost by applying Six Sigma methodology to study factors that influence number of abnormal yield report in order to reduce internal failure cost that is the main of quality cost. The step of study will follow five-phase of Six Sigma methodology which are define phase, measure phase, analyze phase, improvement phase and control phase. For a study of quality cost which are prevention cost 1appraisal cost 1 internal failure cost and external failure cost include in measure phase. In this phase inter failure cost need to improve and the problem are to many abnormal yield report occur. After finishing analysis phase, it was found four key process input variables (KPIVs) which are lot size , input , abnormal yield target and number of 1C per lead frame. Then an experiment of these KPIVs was performed in improvement phase and find optimum KPIVs by optimization theory. After that pre-running using the chosen levels of factors was performed in order to confirm the result. Finally, set the control system in control phase. Before improvement the data of quality cost report in January 2004 are 1,443 baht per 1,000 unit .After improvement, the data are 1,146 baht per 1,000 unit. And it could reduce cost by 297 baht per month per 1,000 unit or 639,738 bath per month estimated form actual order in August 2004.