DOE 田口presentation-Example2.pdf

08L TDFN 1.9*3mm Bond Pad Cratering improvement June 2005 Report: Y.B. Lin (林煜斌) 2007/10/30 Page: 1 Outline Drawing of TDFN Package Plastic Very Thin Fine Pitch Plastic Thin Fine Pitch Quad Dual Flat No Lead Package Flat No Lead Package (TQFN) (TDFN) 2007/10/30 Page: 2 Thin Quad Flat No Lead (TQFN) Process Flow Thin Quad Flat No Lead (TQFN) Process Flow •Lead Frame •Die Attach • Wire Bond • Molding • De-Tapping • Singulation (Package Saw) 2007/10/30 Page: 3 08L TDFN 1.9*3mm Bond Pad Cratering Improvement Background/History The customer highlighted the Open/Short low yield due to cratering on bond pad under bond ball. To address this issue, failure analysis and improvement action were conducted. High FT failure rate of 89.13% (90.24% and 88.95% for 2 split lots) was encountered. Continuity short or leakage of G-S is valid through Bench test Characteristics Curve Tracer for 43 failures. 20 units of 43 failures were further failure analysis indicated silicon cratering under the bond balls. Base upon failure analysis verification, the failure mechanisms of continuity short and leakage should be caused by silicon cratering. 2007/10/30 Page: 4 08L TDFN 1.9*3mm Bond Pad Cratering Improvement Background/History Failure Analysis Findings Figure 1