Tin Whiskers

If you can only find components with pure tin plating, Corfin Industries can mitigate your tin whisker concerns with our Robotic Hot Solder Dipping process. To learn more, please read about our process in our Tin Whisker brochure and in the Military and Aerospace Electronics Magazine article featuring Corfin’s Don Tyler on the GEIA-STD-0006 Standard for Robotic Hot Solder Dip.

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Courtesy of Peter Bush/SUNY Buffalo

A tin whisker is a single crystal that emerges from tin-finished surfaces. It can take hours or years for them to grow, and they can grow up to 9 millimeters in length. Tin whiskers have been blamed for dangerous failures in heart pacemakers, satellites, and nuclear power plants. The NASA Tin Whisker Website provides a wealth of information regarding the nature of tin whiskers and their ability to cause:

  • Short circuits
  • Low pressure arcing
  • Debris and contamination

Any of these issues is a showstopper in electronic assembly. Unfortunately, much of the available electronic component supply is assembled with some degree of pure tin finish, especially on component leads. These leads are extremely vulnerable to tin whiskers and their associated failure mechanisms.

What can be done to eliminate the risk of tin whiskering? Right now, the simplest, most cost effective way to mitigate the danger of tin whiskering is to remove the tin finish – all of it. It has been clearly demonstrated that partial removal of pure tin during the soldering process is not enough. The terminations should then be refinished with a SnPb solder, proven effective over 60 years of service in high reliability applications. Other solutions remain unproven.

Removal of tin and replacement with tin-lead sounds simple, but can it be done reliably and repeatedly?

In 2004 the United States Navy, Raytheon, University of Maryland, and Corfin Industries teamed up for the three-year, $1,250,000, Transformational Manufacturing Technology Initiative (TMTI) project to determine if tin mitigation (the removal of pure tin and replacement with tin-lead solder) could be reliably accomplished using Corfin’s precisely-controlled Robotic Hot Solder Dipping process.

The team designed an exacting process of computer-controlled times and temperatures and precise robotic component positioning to accomplish this task. Corfin’s Robotic Hot Solder Dip process successfully removed the problematic tin finish from a wide variety of components and replaced that finish with non-whiskering tin-lead. All of this was accomplished reliably and repeatedly without damaging sensitive components. To learn more, please read the final study report or Corfin’s Tin Whisker brochure.

If pure tin-finished components are in your inventory and tin whiskers are a concern, please give us a call and talk to us about your lead-free control and whisker mitigation needs.

For more information, please click here to download our Tin Whisker Brochure.