WHISKER GROWTH ON SAC SOLDER JOINTS: MICROSTRUCTURE ANALYSISAuthors: Polina Snugovsky, Zohreh Bagheri, and Marianne Romansky
Company: Celestica International Inc.
Date Published: 5/16/2008 Conference: ICSR (Soldering and Reliability)
Optical and Scanning Electron Microscopy (SEM) with EDX following by cross-sections through whiskers were performed. The analyses revealed that Sn whiskers originated not from the component lead plating as was expected, but from bulk SAC405 or SAC305 solder. A high precision metallographic technique using progressive polishing was developed to examine the details of whisker formation.
This paper discusses the microstructural relationship between the whiskers, hillocks, and shell-like protrusions and the following factors: solder microstructure and its modification during oxidation and corrosion, Alloy 42 lead frame material, lead plating quality, component contamination and flux on solder.
Key words: Whisker, Lead-Free solder, Alloy42, microstructure
Members download articles for free:
Not a member yet?
What else do you get when you join SMTA? Read about all of the benefits that go along with membership.
Notice: Sharing of articles is restricted to just your immediate work group. Downloaded papers should not be stored on an external network or shared on the internet.