Dynamic test and modeling methodology for BGA solder joint shock reliability evaluation

This work developed a dynamic test and modeling methodology for BGA solder joint shock strength evaluation. A test board and a test fixture were designed similar to a four-point bend test. The test setup for BGA evaluation was calibrated to a typical desktop PC motherboard under packaged shock condition. The fundamental frequency of the proposed test setup is matched to that of the motherboard through the experimental modal analysis. The BGA solder joint shock failure envelope was established through the proposed shock test and modeling. With an incremental shock sequence and an in-situ solder joint continuity monitoring setup for the shock events, the G-level (acceleration) and shock duration at BGA solder joint failure was measured. The dynamic finite element analysis was performed with the experimental input and the test board dynamic response to the measured solder joint failure shock level was simulated. The failure strengths of the solder joints were estimated with different BGA orientations on the test board. A preliminary solder joint failures envelope under dynamic load is established, which represents key board and system levels shock conditions.