Chip Testing Yield Optimization With Commonality Analysis And MBPS Method

The research of yield optimization in semiconductor chip assembly test manufacturing,is seldom mentioned in domestic and foreign literatures,most of which focus on the yield optimization of wafer testing.Using the analysis based on big data to make yield prediction,analyzing the relationship between input parameters and output yield,and excavating to discuss valuable information,control the parameter of products.In this way,the yield will be improved and quality will be controlled,so that the cost reduction achieved.The yield optimization of chip assembly test manufacturing,focuses on the commonality analysis method which traces the failure factor cause by the yield loss.This failure factor could be caused by operator,production equipment,material,designed defect and manufacturing environment.Once the failure factor is captured,while effective actions should be taken immediately to prevent the continuous yield loss.Which is the concept of Corrective Action,it's the abbreviation of a series of activities aiming at the failure factors,and it is the most direct and effective solution for failure factor.Detecting the failure factor through the commonality analysis method and preventing the continuous yield loss through corrective actions is first step to solve the issue.It could avoid the continuous yield loss in the short term.How to avoid the repeat problem happen is the next step which is most important.This paper bases on mathematical statistics to provide MBPS(Model-based Problem Solution),the principle of which is studied,and proves its effectiveness in failure mode analysis.The practical application of MBPS applied in chip testing yield technologic procedure optimization is illustrated with examples.Engineering experiments show that MBPS is a very effective method for analyzing failure modes in chip assembly test manufacturing yield issues.When the contributor of failure model is clearly understood,and effective actions are executed,the same type of yield loss could be prevented from repeating,which is Preventative action.Taking preventative actions could fundamentally solve the problem of yield loss induced by one certain kind of failure factor,then chip testing yield is optimized.To apply this method in yield issue from five essential factors(people,machine,material,design defect and environment)of chip assembly test manufacturing,failure factor will be traced by commonality analysis and addressed by corrective action,meanwhile,failure mode will be figured out by MBPS and addressed by preventative action.The availability of this method is proved by yield improvement.And apply it in the process control system of semiconductor assembly and test,it will automatic alarm when the early failure signal triggered,then the pointed failure unit will be checked by required technician who worked at suspected issue process station,tacking effective action in the early state of issue,which avoid the yield loss increase.