Legislation that mandates the banning of lead in electronics due to environmental and health concerns has been actively pursued in many countries during the past fifteen years. Although a large number of research studies have been performed and are currently under way in the lead-free solder area, especially on the reliability of lead-free solder joints, abundant data exists predominantly on the short-term reliability (that is, less than five years) of lead-free solder joints under single-loading conditions. Data on long-term reliability is scarce. Lead-free electronics will be deployed in many products that serve markets where long-term reliability is a critical requirement. This paper presents a design-of-experiment reliability study of lead-free solder joints. The printed circuit board (with different base materials: FR4, HT-FR4, and PI) test assemblies include two types of components (PBGA and 2512 resistors), with various terminal metallurgies, several PCB pad finishes (HASL, ImSn, ImAg, ENIG, and OSP), and two solder alloys (SnPb and Sn3.0%Ag0.5%Cu). The test vehicle design, experimental set-up, results, and failure analysis are presented here.
[1]
Johan Liu,et al.
Effect of different temperature cycle profiles on the crack propagation and microstructural evolution of lead free solder joints of different electronic components
,
2004,
5th International Conference on Thermal and Mechanical Simulation and Experiments in Microelectronics and Microsystems, 2004. EuroSimE 2004. Proceedings of the.
[2]
Michael Pecht,et al.
Lead-free Electronics
,
2006
.
[3]
S. Ganesan,et al.
Using cut-out features for efficient printed circuit board testing and failure analysis
,
2005,
IEEE Transactions on Components and Packaging Technologies.
[4]
P. Lall,et al.
Thermal cycling reliability of lead free solders for automotive applications
,
2004,
The Ninth Intersociety Conference on Thermal and Thermomechanical Phenomena In Electronic Systems (IEEE Cat. No.04CH37543).