We search for industry news, so you don't need to.
Ask the Experts  
Questions Index  ■  Submit a Question  ■  Experts Panel  ■  Join the Panel

April 23, 2007

Soldering reliability using SAC 305 . . .

What is the impact on reliability soldering parts using SAC 305 solder paste on 63/37 HASL pads?


Experts Comments

Mixed metal manufacturing is, in fact, quite commonplace in today's manufacturing environments. Most often, due to component and board availability issues, we see lead-free finished devices being used in an otherwise Pb-free process. But, the reverse as you've asked here is also a fairly frequent occurrence.

In either case, the most common problem with leaded devices and mixed metal manufacturing is improper wetting and through analysis and reflow profile adjustment, sometimes acceptable wetting can be achieved. But more severe problems exist when processing BGAs and CSPs in this environment.

In this case, incomplete bump melting or collapsing occurs. The goal is to promote even distribution of lead throughout the solder joint, but, if the bump doesn't melt completely, achieving this condition is impossible. Without the lead evenly dispersed within each solder joint, premature joint cracking and early thermal fatigue are the most likely outcomes, yielding uncertain device reliability.

Mixed metals may also put you out of tolerance with RoHS. Shipping product to Europe with mixed metal assembly methods may be setting your company up for penalties or fees due to lead content in the solder joints.

For more information, please click on this white paper.

Doug Dixon
Global Marketing Director
Henkel Electronics
Mr. Dixon has been in the electronics field for over twenty years and is the Global Marketing Director with the electronics group of Henkel. Prior to joining Henkel, he worked for Raytheon, Camalot Systems, and Universal Instruments.
Submit a Comment

Your Name

Your Email

Company Name




Please type the number displayed into the box. If you receive an error, you may need to refresh the page and resubmit the information.