Title :
Interfacial IMC and Kirkendall void on SAC solder joints subject to thermal cycling
Author :
Xu, Luhua ; Pang, John H L
Author_Institution :
Sch. of Mech. & Aerosp. Eng., Nanyang Technol. Univ., Singapore
Abstract :
The effect of thermal cycling on lead-free solder joints reliability was reported. The IMC compounds growth, Kirkendall voids formation and interconnect failure mode are characterized on SAC/Cu-OSP interface. The growth of interfacial CuSn IMC was observed after thermal cycling aging of 500, 1000 cycles, and faster IMC growth was found compared to isothermal aging with the proposed comparison criteria. Kirkendall voids were observed after Ar+ sputtering etching. Growth of Kirkendall void during TC aging was found in the Cu3Sn layer or at Cu-Cu3Sn interface. Coalesce of voids weakened the interface and decreased the drop reliability significantly
Keywords :
argon; chemical interdiffusion; copper alloys; silver alloys; solders; sputter etching; thermal management (packaging); tin alloys; voids (solid); Ar; Cu-Cu3Sn; CuSn; IMC compounds growth; Kirkendall voids formation; SAC solder joints; SAC/Cu-OSP interface; SnAgCu; TC aging; interconnect failure mode; interfacial IMC; intermetallic compounds; isothermal aging; lead-free solder joint reliability; sputter etching; thermal cycling aging; Aging; Assembly; Circuit testing; Environmentally friendly manufacturing techniques; Fatigue; Isothermal processes; Lead; Soldering; Sputter etching; Sputtering;
Conference_Titel :
Electronic Packaging Technology Conference, 2005. EPTC 2005. Proceedings of 7th
Conference_Location :
Singapore
Print_ISBN :
0-7803-9578-6
DOI :
10.1109/EPTC.2005.1614520
