Static and dynamic flexure of PCBs in electronic packaging assemblies

Abstract

Portable electronic products such as mobile phones are prone to being bent when dropped during usage. This causes electrical failure arising from cracks in the circuit boards as well as solder interconnections.Here, we performed three- and four-point bend tests, as well as dynamic drop tests on different electronic packaging assemblies to evaluate how the board responses affect the integrity of solder interconnections. In addition, an in-depth finite element parametric study was undertaken to examine the static and dynamic behaviours of solder interconnections. Design optimization of electronic packaging assemblies is possible based on an understanding of the relationship among quantities such as board flexural strength, solder interconnection stress, dynamic board deflection and dimensional and material parameters. Based on experimental results, simulated board responses and parametric studies of static and dynamic loading, this investigation yielded insights into the mechanics of failure in solder interconnections. Consequently, design optimization of electronic packaging assemblies can be established to improve the physical robustness of portable electronic products against static and dynamic loads.