Application Of Six Sigma DMAIC Methodology In DF Company Cost Reduction

Six Sigma is a quality control method that is used in organizations to improve quality, reduce cost and eliminate variations from process. It is a certified and powerful tool applied in improving manufacturing process&product’s yield (reducing defect), enhancing and consolidating business’s competency, increasing market share and customer satisfaction as well. The core of market competition is:Quality, Cost and Service. How to make big improvement on them depends on advanced quality management level, so it’s essential to study Six Sigma quality management and apply Six sigma methodology in product’s yield improvement and cost reduction.DF semiconductor company is one of world leader in micro-controller and processor, but it is still under high pressure of improving product’s quality and cost reduction. So the most important is to promote6-Sigma project to increase product output by reducing product defect, and to realize product unit cost down. Otherwise, there’s high risk of losing customer because of expensive product, and the company will loss market share. So it’s essential to deploy6-sigma projects in our company, and it’s one of company’s business strategy. Wafer Back Grinding (WBG) department is one department of DF company, its manufacturing process is to grind wafer to be280um or less from original thickness780um. High wafer breakage rate and high cost of DI wafer filter are two major factors which have significantly impacted DF company’s unit cost. So this thesis is a real practice of how to use DMAIC methodology to make improvement on both two side mentioned above. The works done in this thesis are as following:1.Identifying the Problem:Formed project team; Analyzed the defect distribution with Pareto chart; Defined the project target:wafer breakage rate reduces to0.033%from0.067%, and DI water filter’s cost has50%reduction. The estimated benefit is cost saving RMB2000K/year.2. Verifying the measuring tools validity; Analyzed and list all potential factors with fish bone analysis methodology; Made data collection plan.3. Digging out two key factors of causing wafer breakage with FMEA methodology tool (Failure Mode Effect Analysis):one was’Incoming wafer inspecting procedure’, and the other one was’wafer edge hits by grinder’s positioning roller’; Analyzed their root cause with hypothesis methodology. Made DI water filter replacement plan.4. Conducting improvement actions:Verified the improvement action work or not with data comparison between’before and after action’; Defined the root cause and corresponding improving actions; Verified that the new filter’s quality equal to the original’s.5. Standardized the control method with documentation; Revised SOP (Standard Operating Procedure); Consolidated the project result by conducting trainings to operators as well as maintenance technicians and hand over related documents to production department.Finally, with more than8months effort, we achieved and exceeded project targets: wafer breakage rate reduced to0.023%from0.067%, cost saving RMB2505K/year; filter’s annual cost reduced to RMB102.5K/year from RMB436.8K/year, the total benefit from this project is annual cost saving RMB2838K, exceeded the original target. We won the Manufacturing Excellence Award by this project. This thesis bridge the gap between Six Sigma DMAIC methodology and actual manufacturing quality improvement and cost reduction, it’s a reference to others who wants to apply Six Sigma DMAIC quality management in actual work.