Failure analyse of the welding point in flip-chip BGA packages in the drop-free

The failure of plastic ball grid array in vibration and shock under intense dynamic loading will be studied in the project. This paper presents the drop test reliability results for SnPb flip-chip on a standard JEDEC drop reliability test board, the failure mode and mechanism of planar array package in the drop test will be integrated analyzed. High acceleration dropping test method was used to research the reliability of BGA (ball grid array) packages during the drop-free impact process. The model RS-DP-03A drop device was used to simulate the falling behavior of BGA chip packages under the real conditions, dropping from the 650mm high, the drop condition meets the JEDEC22-B111 standards (pulse peak 1500g, pulse duration 0.5 ms). In the testing, based on the real-time changes of dynamic voltage, the relationship between dropping times and different phases of chip failure was analyzed. Solder crack and pad lift failure locations are characterized with the dye-penetrated method and optical microscopy. Stain tests were carried on the expired chip packages, the failure position of solder joints and the internal appearance of cracks were observed; the growth mechanism of solder ball crack under the condition of drop-free was analyzed and discussed.