Characterization and Failure Analysis of Solder Joints in Ball Grid Array (BGA) Components Using Cross-Section, Dye and Pry, and Microstructural Etching Techniques

This study investigates failures in solder joints of Ball Grid Array (BGA) components using destructive techniques such as cross-section, dye and pry, and chemical etching with metallographic reagents. Discarded printed circuit boards (PCBs) from the University of the State of Amazonas (UEA) were reused, with a focus on the SAC305 alloy. The samples were analyzed using optical microscopy. The dye and pry analysis revealed fractures in the intermetallic compound (IMC) layer and "Type E" staining (according to IPC-TM-650 2.4.53). Cross-section confirmed cracks in the IMC layer and macrovoids at the solder-PCB interface, including shrinkage voids associated with solidification, as per IPC-7095E standards. The microstructure of the SAC305 alloy exhibited silver and copper precipitates within a dendritic tin matrix. The research highlights the importance of destructive testing for evaluating solder joint reliability, preventing failures in electronic components.