This seminar provides an extensive coverage of lead-free attachment reliability issues and trends and offers practical guidelines to assess the reliability of lead-free solder joints and circuit board assemblies. Participants will gain an in-depth understanding of the multitude of material, design and manufacturing parameters that affect solder joint reliability and that are critical to the deployment of lead-free circuit board assemblies. Following a review of the basics of solder joint mechanics, test procedures, failure modes and mechanisms, the seminar puts in perspective a wide range of lead-free data, material properties, test and modeling results from across the industry. Test results are discussed for common components (leadless, leaded, BGA, Flip-Chip, CSPs), including the effect of board and component finish on lead-free reliability, and a comparison of tin-lead, mixed assemblies and lead-free reliability data. Metallurgical risks, creep properties and fatigue curves are examined that explain differences in the reliability of tin-lead and lead-free assemblies. Examples of strain-energy based life prediction models and acceleration factors are presented, comparing test efficiency for SAC and SnPb assemblies and illustrating how to extrapolate lead-free test results to product use conditions, the true measure of lead-free assembly reliability.

The tutorial is technical in nature and pulls together a wide range of data, material properties, test and modeling results from across the industry. Lessons learned from the tin-lead experience and fundamental differences between SnPb and lead-free solders are highlighted as well as recent progress in the practical understanding of lead-free solder joint reliability. Pre-requisites: none although some basic understanding of the mechanical behavior of materials is helpful. In addition to the printed seminar hand-out, participants will receive the .pdf version of an extensive reference list on SnPb and lead-free solder joint reliability.

WHAT YOU WILL LEARN

• The basics of solder joint reliability, plus an overview of trends in SAC vs. SnPb accelerated testing results.
• Fundamentals and lessons learned from the SnPb experience: solder joint mechanics, creep-fatigue interaction, life prediction techniques. Assembly quality and reliability: defects and their impact on product life.
• Accelerated testing procedures, failure modes and mechanisms, failure statistics.
• Identify potential risk areas (metallurgical risks, ductile-to-brittle transition, interfacial failures...).
• How to plan for lead-free product reliability assurance and why inferior test results — when compared to SnPb -- do not necessarily imply lessened product reliability.
• Gain an understanding of fundamental differences in microstructure, creep mechanisms and the thermo-mechanical response of SnPb and SAC alloys.
• Understand the effect of thermal cycling dwell times on the relative lives of SnPb and SAC assemblies.
• Find out how to optimize lead-free accelerated thermal cycling profiles for maximum efficiency (and reduced cost) without lengthening test duration.
• How to interpret test results; strain-energy based life prediction models; examples of acceleration factors for SAC assemblies, including validation data.

TOPICS (partial list)