| dc.description.abstract | Six Sigma focus on demand of customer. Via understanding customer’s needs and making improvements, it can not only eliminate variability and reduce costs, but also enhance quality of customer service and satisfaction. It’s also can improve efficiency, performance and profitability for the company. The well effectiveness of improvement is the reason why Six Sigma are still widely used in various fields.
This study take C company as an example to study the rejection rate of solder balls by using the method of Six Sigma, and find the root cause of the problem with the steps of DMAIC. Then take actions for improvement, and standardize the documents to improve the rejection rate of solder balls.
In Define stage, we collect voice of customer (VOC), understand key customer requirement, identify critical to quality (CTQ) and quantify the goals that need to be improved, and use the SIPOC chart to clarify the relationship between suppliers and customers. In Measure stage, we define the measurement plan first, using the measurement system analysis (MSA), confirm the consistency of the measurement tools. Then we confirm the process capability and define the performance target. In Analysis stage, the main purpose is to analyze what’s the main reason that cause solder balls, and focus on the problems that cause solder balls. Then we use 3WHY analysis and Pareto Chart to confirm the root causes, and improve them. In Improve stage, we improve the items that need to be improved, formulate and implement corrective actions, and verify the effectiveness of corrective actions. Then we use hypothesis testing to test the significance level. At last, in Control stage, we standardized corrective actions to maintain the effectiveness of the improvement.
As a result of the improvement, the rejection rate of solder balls was reduced and saved rework costs. The results of this research show that Six Sigma can not only improve quality, but also reduce rework costs, save waste of rework man-hour, and can use this method and tools to improve other processes that need to be improved. The effect of getting twice the result with half the effort. | en_US |