EFFECT OF LONG-TERM AGING ON LEAD-FREE SOLDER AND SURFACE FINISH

Abstract

Since 2006, commercial electronics manufacturers have been banned from using lead-based materials and other toxic materials in their products due to the RoHS directive from the European Union. This led to industries transitioning to lead-free materials to be used in solder and surface finishes of their products. Although all of commercial electronics industry has transitioned to lead-free materials, some of the reliability and safety critical products used in industries such as defense, aerospace, automobile, and healthcare sectors are still exempted from the lead-free regulation. These industries are hesitant to transition to lead-free due to lack of data and hence the confidence on the long-term reliability of lead-free electronics. Known issues of tin whiskers and solder interconnect fatigue which can arise later in a products life have raised concerns related to the use of lead-free materials in electronic assemblies. To address these concerns, 10 year old lead-free systems were examined to determine the solder interconnect degradation level and tin whisker risk level.