Mechanical Property Evaluation of Sn-3.0A-0.5Cu BGA Solder Joints Using High-Speed Ball Shear Test

The traditional ball shear test is not suitable for evaluating joint reliability under drop loading, since the applied test speeds, usually lower than 5 mm/s, are well below the impact velocity applied to the solder joint in a drop test. The present study expands recently reported research by investigating the effect of thermal aging on the joint strength and fracture mode of Sn-3.0Ag-0.5Cu ball grid arrays during high-speed shear testing, with a shear height of 50 μm and a shear speed ranging from 0.01 m/s to 3 m/s. The test specimens were aged at 393 K for 1000 h. After reflow, a (Ni,Cu)3Sn4 intermetallic compound (IMC) layer was observed at the solder/Ni-P interface and the thickness of the IMC layer was increased through the aging process. The shear strength increased with increasing shear speed. The fracture surface of the solder joints showed three different fracture modes according to the shear speed and aging time. The fracture mode changed from ductile fracture to brittle fracture with increasing shear speed.

[1]  Yi-Shao Lai,et al.  Empirical correlation between package-level ball impact test and board-level drop reliability , 2007, Microelectron. Reliab..

[2]  John H. L. Pang,et al.  Drop Impact Reliability Testing for Lead-Free and Leaded Soldered IC Packages , 2005, Proceedings Electronic Components and Technology, 2005. ECTC '05..

[3]  W. Peng,et al.  Effect of Thermal Aging on Drop Performance of Chip Scale Packages with SnAgCu Solder Joints on Cu Pads , 2007 .

[4]  R. Armstrong,et al.  Dislocation-mechanics-based constitutive relations for material dynamics calculations , 1987 .

[5]  S. R. Bodner,et al.  Constitutive Equations for Elastic-Viscoplastic Strain-Hardening Materials , 1975 .

[6]  Jong-Woong Kim,et al.  Reexamination of the solder ball shear test for evaluation of the mechanical joint strength , 2006 .

[7]  Willem D. van Driel,et al.  Correlation studies for component level ball impact shear test and board level drop test , 2008, Microelectron. Reliab..

[8]  A. Nádai.  Theory of flow and fracture of solids , 1950 .

[9]  Seung-Boo Jung,et al.  Evaluation of displacement rate effect in shear test of Sn-3Ag-0.5Cu solder bump for flip chip application , 2006, Microelectron. Reliab..

[10]  A. R. Zbrzezny,et al.  Impact of board and component metallizations on microstructure and reliability of lead-free solder joints , 2007, Microelectron. Reliab..

[11]  Jong-Kai Lin,et al.  Failure Morphology After Drop Impact Test of Ball Grid Array (BGA) Package With Lead-Free Sn–3.8Ag–0.7Cu and Eutectic SnPb Solders , 2007, IEEE Transactions on Electronics Packaging Manufacturing.

[12]  Seung-Boo Jung,et al.  Effect of displacement rate on ball shear properties for Sn-37Pb and Sn-3.5Ag BGA solder joints during isothermal aging , 2007, Microelectron. Reliab..

[13]  Jorma Kivilahti,et al.  Failure mechanisms of lead-free chip scale package interconnections under fast mechanical loading , 2005 .

[14]  H. Reichl,et al.  A study on interfacial reactions between electroless Ni-P under bump metallization and 95.5Sn-4.0Ag-0.5Cu alloy , 2003 .

[15]  Sang-Su Ha,et al.  Mechanical reliability evaluation of Sn-37Pb solder joint using high speed lap-shear test , 2008 .

[16]  Y. L. Lin,et al.  Effect of Cu concentration on the reactions between Sn-Ag-Cu solders and Ni , 2002 .

[17]  Jeong-Won Yoon,et al.  Influence of Shear Speed on the Shear Force of Eutectic Sn-Pb and Pb-Free BGA Solder Joints , 2004 .

[18]  Yi-Shao Lai,et al.  Experimental studies of board-level reliability of chip-scale packages subjected to JEDEC drop test condition , 2006, Microelectron. Reliab..

[19]  Jong-Woong Kim,et al.  Experimental and finite element analysis of the shear speed effects on the Sn–Ag and Sn–Ag–Cu BGA solder joints , 2004 .

[20]  Xiaoming Xie,et al.  Effect of Interfacial Reactions on the Reliability of Lead-Free Assemblies after Board Level Drop Tests , 2007 .