Six Sigma Approach in Resolving Tapeless QFN Top Backetching Defect

— VPLGA (Very thin Plastic Land Grid Array) or Tapeless QFN-mR (Quad Flat No leads – Multi Row) has a lot of gain in comparison with similar package HVQFN which includes cheaper leadframe cost, capable for multi-row leads, copper wire compatible, no tape and faster sawing speed at package singulation. Product application is on hard disk drives. However, leadframe configuration no longer has barrier in the form of a tape at backside to prevent bottom plating from being disturbed thereby exposing the copper based on the leads and the pad during backetch process. This technical paper will use six sigma approach via DMAIC to address expose copper on all tapeless QFN packages. Statistical tools such as MSA, multi-vari chart, 2-proportion test, correlation and capability analysis was used to properly guide analysis and make tapeless QFN robust thereby reducing expose copper defect.