This study aims to demonstrate the application of the DMAIC-based Six Sigma methodology to reduce defective products in the manufacturing of temperature control device Model A. This research was begun with the Define Phase to define the scope of the project. A process flow chart was constructed, followed by a Pareto analysis that identified excessive solder and solder short as the key defect types. This then proceeded to the Measure phase to determine current status of the process and analyze the measurement system. One year of data (January to December 2024) showed defective products accounted for 17.8% of total production volumes. Attribute Gage Repeatability and Reproducibility results showed the measurement system was reliable. In the Analyze phase, the objective was to identify defect causes using Fishbone diagrams and prioritize them by Risk Priority Number (RPN) based on expert operator evaluation. The project then moved into the Improve phase, aiming to reduce defects by applying ECRS principles such as flux concentration control, solder paste inspection, conveyor speed standardization, stencil pressure control using jig, and the auto optical inspection machine. In the final Control phase, aimed to sustain improvements, a Control Plan was formulated to train the workforce. Monitoring for 3 months after these improvements found that the ratio of defective products fell from 17.8 to 10%, demonstrating that the application of Six Sigma methodology significantly contributed to defect reduction and increase the efficiency of manufacturing processes for electronic devices.

Keywords

Six Sigma, Defective Products, DMAIC, Process Improvement, Electronic.