Board Design Influence on BGA Mechanical Reliability

Abstract

With the technology trend moving towards faster, smaller, and cheaper products, the consumer electronics industry is using more and more high density fine pitch BGA components in a lead-free environment. This has created additional board-level solder joint mechanical reliability challenges. Current literature studies mostly focus on the impact of component design features on BGA solder joint reliability. Very little information is available on board design factor impact on BGA mechanical reliability. This paper highlights the results of our study on the sensitivity of three critical board assembly design factors on BGA solder joint interconnect reliability under mechanical shipping stresses. The results from this study showed high sensitivity to the component location on the board, board trace routing orientation under the component, component enabling heat sink retention mechanism design, and neighboring component heat sink mass. The data collection also showed multiple failure modes including BGA solder joint cracks, PCB pad craters, and PCB trace cracks. Finite element analysis (FEA) modeling results correlated well with empirical data collection and provided additional insight into the physics behind the failures. In conclusion, the paper provides design for reliability (DFR) recommendations to proactively identify high risk bend-line zones to prevent BGA and PCB failures through predictive modeling. This methodology enables board designers to optimize electrical and thermal design and build a mechanically reliable product. IntroductionThe consumer electronics industry is trending towards faster, smaller, and cheaper products with increased product functionality. This has led to an increase in demand for fine pitch BGA components with smaller feature sizes and high

Board level vibration test method of components for automotive electronics: State-of-the-art approaches and challenges

“…The experimentally obtained PCB resonance frequency is validated by the FEM results. A similar technique is used in [27,28].…”

Experimental Validation of Fatigue Life of CCGA 624 Package with Initial Contact Pressure of Thermal Gap Pads under Random Vibration Excitation

“…Several previous studies have focused on securing the mechanical safety of a solder joint under vibration excitation by applying mitigation techniques to the package, such as applying an underfill or dummy solder balls [6][7][8]. Kim and Hwang [6] investigated the effect of underfill on the fatigue life of a plastic ball grid array (PBGA) package for space usage under random vibration excitation of the launch.…”

“…The results of the fatigue test under harmonic vibration showed that applying dummy solder balls improved the fatigue life of the given SSD by 4.5 times by reducing the stresses on the functional solder balls. Uppalapati et al [8] investigated the sensitivity of three critical PCB design factors on the mechanical safety of the solder joint of a flip-chip ball grid array under vibration during shipping. The results showed high sensitivity with respect to the location of the package on the PCB, trace routing orientation of the PCB under the package, retention mechanism design, and mass of the heat sink.…”

“…Thus, a proper thermal management of high-heat-dissipating packages is important to prevent failure of spaceborne electronics used in a severe space thermal environment. In general, thermal gap pads act as essential hardware for heat sink implementation by enabling heat transfer path between the high-heatdissipating packages and a heat sink to avoid an excessive increase in temperature during their operation [8,9]. The heat transfer capability of the thermal pads can be enhanced by controlling the initial contact pressure level of the pads during the assembly process of heat sinks.…”

Solder stability for Pb-free HBGA assembly with oxygenous reflow

“…Since the high-pin count package over 200 pins is desired more for high profit products, the ball-grid-array (BGA) package technology [1,2] is dramatically raised up in assembly industry. Because of the high power consumption in BGA type, some products requiring the high stability operation need a heat sink as an assistant to dissipate more Joule heat.…”