Abstract
In recent years, with the rapid growth of smart phones and the popularization of mobile internet, smart phones have become a consumer electronic product that everyone poses, thus the market has saturated. With high product homogeneity, the market is becoming saturated. Smart phone is entering the slow growth stage. With the numerous competitors entered in the smart phone market, the product life cycle is relatively shortened. In order to responding to the market trend and maintain profitability. The fundamental action of Smartphone manufacturers is to meet the anticipation of customer while reduce the frequency of quality failure that leads to customer complain and extra expense on service. This study is set to investigate the subject by examine the improvements of mass production through Six Sigma “DMAIC” on solving collateral design issue of interference noise caused by pressing LCD screen when playing music. First, listen to the customer's voice, clearly define the improvement of the target and set a measurable performance indicator. Next, empirical analysis via Kappa coefficient to assess the reliability of investigation and adapt p chart is used to realize the status of the process as a basis for improvement.Then, Cause and Effect Diagram is used to analyze the possible causes of abnormality, and Cause and Effect Matrix is used to identify the real factors causing the defect. Last, the results of the improvements is structure to optimize the production flow and prevent variable that influence the production.The improved model is design to implement to the production flow as a long lasting monitoring tool to prevent recurrence of the abnormality. After implementing the improved model, the production defective rate was reduced from 6.1% to 52dppm and internal failure costs of NT$14,119,154 was saved. The result of this study can be served as a reference and foundation for future study .