Lead-Free solder joint reliability

Abstract

Lead-free solder joint reliability is a multi-faceted and challenging topic. Lead-free solders such as eutectic SnAg and SnBi have been used successfully in niche applications for many years. With the advent of no-lead (Pb) legislation, a multitude of soldering alloys has been proposed for mainstream electronic applications. The high number of lead-free alloy options remains a major factor slowing the development of reliability databases, test standards, acceleration factors and life prediction models. While the electronics industry has over fifty years of experience working with a single, main stream alloy -near-eutectic SnPb solder -the engineering community now faces the daunting task of qualifying product assemblies for an increasing variety of lead-free solders such as SnAgCu, SnAg, SnAgBi, SnBi, SnCu, SnZn alloys of near-eutectic or other compositions, some with known additive elements (e.g., nickel, cobalt, germanium) and others with proprietary compositions. © 2007 Springer-Verlag US.