Experimental and finite element analysis of cavity down BGA package solder joint reliability

Solder joint reliability is one of the most critical issues for successful application of BGA packages in the electronics industry. In this study, both temperature cycle tests and finite element analysis were used to analyze the solder joint thermal fatigue life of a fine pitch Cu-based cavity down BGA. Three board level reliability results on a cavity down Cu based BGA with 680 balls show that it meets the commercial application requirements of the industry. The 3D finite element slice model based on volume weighted average viscoplastic strain energy accumulated per temperature cycle for the interface elements has been successfully applied to FG680. The model is useful for future assembly parameter evaluation in very short periods