Avoid the Void®: Voiding in Gold-Tin (AuSn20) Solder Joints:
For years, people have been using gold-tin in high-temperature applications, but we have the ongoing problem of voiding. It's not just high-temperature applications, but LED applications where the high thermal electrical connectivity are a prerequisite for the usefulness of the solder. What we've noticed is that, in the last several years because people have been using gold plating on both the die side, and on the substrate side, certainly the substrate side in some instances, there's been an increase in voiding that's been seen, and it seems to correlate with the amount of gold that's present from those.