SMTA International

PDC13: Solder Joint Reliability – Principles and Applications

Jennie Hwang, Ph.D., H- Technologies Group
Monday, October 14 | 8:30am — 12:00pm

Course Objectives
The course emphasizes on practical, working knowledge, yet balanced and substantiated with science by outlining solder joint reliability fundamentals in fatigue and creep damage mechanisms via ductile, brittle, ductile-brittle fracture, and by discussing the critical “players” of solder joint reliability (e.g., manufacturing process, PCB/component coating surface finish, solder alloys). Likely solder joint failure modes of interfacial, near-interfacial, bulk, inter-phase, intra-phase, voids-induced and surface cracks will be illustrated. To withstand harsh environments, the strengthening metallurgy to further increase fatigue resistance and creep resistance, and the power of metallurgy and its ability to anticipate the relative performance will be illustrated by discussing the comparative performance vs. metallurgical phases and microstructure. The question on whether a life-prediction model can assure reliability will be discussed. A relative reliability ranking among commercially available solder systems, as well as the scientific, engineering and manufacturing reasons behind the ranking will be outlined. Attendees are encouraged to bring their own selected systems for deliberation.

Topics Covered
1. Premise – reliability, solder joint thermo-mechanical degradation – fatigue and creep interaction
2. Solder joint failures modes - interfacial, near-interfacial, bulk, inter-phase, intra-phase, voids-induced, surface-crack, and others
3. Solder joint failure mechanisms – ductile, brittle, ductile-brittle transition fracture
4. Solder joint strengthening metallurgy
5. Illustration of microstructure evolution vs. strengthening in Sn Cu+x,y,z and SnAgCu+x,y,z systems
6. Solder joint voids vs. reliability - causes, effects, criteria
7. Solder joint surface-crack –causes, effects
8. Distinctions and commonalties between Pb-free and SnPb solder joints
9. Thermal cycling conditions - effects on test results and test results interpretation
10. Testing solder joint reliability – discriminating tests and discerning parameters
11. Life-prediction model vs. reliability
12. Solder joint performance in harsh environments
13. What solder alloys are on the horizon and what impact will be on reliability
14. Best practices and competitive manufacturing
15. Ultimate reliability