Issue link: https://iconnect007.uberflip.com/i/881969
October 2017 • SMT Magazine 75 RELIABILITY OF ENEPIG BY SEQUENTIAL THERMAL CYCLING AND AGING Figure 8: Representative SEM photomicrographs of LGA1156 solder conditions under the die after 200 thermal cycles (–55°C/+125°C), (left), and after subsequent 324 hours of isothermal aging at 125°C (right). Samples were the same—half used after TC—and the other half was used for subsequent aging, polishing, and SEM imaging. Figure 7: Representative SEM images with SEM EDS elemental analysis (e.g., showing existence of Ni, Cu, Sn, and Pb) at the solder interface after 200 thermal cycles (-55°C to +125°C).