SMTA International

PDC19: Reliability of Electronics – the Role of Intermetallic Compounds

Jennie Hwang, Ph.D., H- Technologies Group
Monday, October 14 | 1:30pm — 5:00pm

Course Objectives
Intermetallic compounds play an increasingly critical role to the performance and reliability of solder interconnections in the chip level, package level and board level of lead-free electronics. This course covers the relevant and important aspects of intermetallic compounds ranging from scientific fundamentals to practical application scenarios. Intermetallic compounds before solder joint formation, during solder joint formation and after solder joint formation in storage and service will be examined. The course also discusses intermetallics at-interface and in-bulk, as well as the role of PCB surface finish/component coating in relation to intermetallics, in turn, to reliability. The difference between SnPb and Pb-free solder joint in terms of intermetallic compounds, which affects production-floor phenomena and the actual field failure, will be outlined. The course will also address the newer lead-free alloys that were recently introduced to the market. Attendees are welcome to bring their own selected systems for deliberation.

Topics Covered
1. Intermetallic compounds – definition, fundamentals, characteristics
2. Phase diagrams of Pb-free solders in contrast with SnPb
3. Intermetallic compounds in the intrinsic material- Pb-free vs. SnPb
4. Formation and growth during production process and in product service life
5. Intermetallic compounds - at-interface vs. in-bulk
6. Effects from substrate compositions (hybrid module thick film pads, PCB surface finish, component surface coating)
7. Gold embrittlement
8. Different types of intermetallic compounds – effects on solder joint reliability (Ni/Au, Ni/Pd/Au, Ni/Pd, Cu)
9. SAC alloys incorporated with various doping elements – characteristics, performance
10. Effects on failure mode
11. Effects on reliability