Global PCB Connections: Rigid-flex and Flexible PCBs—The Backbone of Modern Electronics
Flexible Thinking: The Key to a Successful Flex Circuit Design Transfer
Happy’s Tech Talk #29: Bend-to-Install Semi-flex FR-4
Has the Time Finally Come for Tin-nickel Plating?
December 9, 2024 | Marcy LaRont, PCB007 MagazineEstimated reading time: 1 minute
In the 1980s, Electrochemicals, Inc. (now Electrochemical Products) made a significant shift from furniture and industrial goods to electronics and manufacturing. During this journey, a tin-nickel plating alloy was developed. In 1984, Mike Carano, a young engineer, published a paper on tin-nickel plating alloy, but after some initial attention, the plating solution fell into obscurity.
Today, PCB fabrication looks largely the same, yet changes are afoot, chiefly due to the demands for very fine feature capability on printed circuit boards, as well as environmental sustainability. So, in this fascinating conversation with Mike Carano and Happy Holden, we take another look at tin-nickel and its advantages in both performance and sustainability.
Marcy LaRont: Mike, please explain the unique metal properties of the tin-nickel alloy and why fabricators should consider this as a surface finish solution today.
Mike Carano: Tin-nickel is a metastable alloy. It is monatomic, meaning that no matter what you do with the chemistry or how you manipulate the grams per liter of one metal or the other (or the amps per square foot), it always comes out as 65% of one metal and 35% of the other. I’m not aware this is true with any other combination of metals.
Typically, if your chemistry is out of balance—if you have more tin in the solution than you have lead—you will plate more tin. It’s precisely why there are so many alloys out there. In that respect, tin-nickel is pretty amazing.
Happy Holden: When I was at Hewlett-Packard, Dr. Morton Adler from Bell Labs called me and said he wanted us to fab his boards using tin-nickel, because he knew we were using it. I plated the boards with tin-nickel and added a gold strike. This thin gold was cobalt-hardened and the final thickness was still only 3–5 microinches when we finished. About a month after I sent them back to Adler, I got another call. He said, “What the hell did you send me? We’ve completed our reliability testing and your 3–5 microinches on tin-nickel outperforms our 120 microinches of sulfamate nickel on our contacts and other relays.”
Continue reading this conversation in the November 2024 issue of PCB007 Magazine.
Share on:
Suggested Items
I-Connect007 Observes U.S. Independence Day Holiday
07/04/2025 | Nolan Johnson, I-Connect007Today marks the 248th anniversary of the signing of the American Declaration of Independence by the Continental Congress. Known widely in the U.S. as Independence Day or “The Fourth of July,” this day also commemorates the declaration by the Congress that the American colonies are free and independent states.
Stop Using Spreadsheets—and You Can Quote Me on That
07/03/2025 | Nolan Johnson, SMT007 MagazineMeeting changing business needs and a thriving market sometimes means process efficiencies. Not all those efficiency improvements take place on the shop floor, however. For EMS companies, growth can also mean changing out the business operations software to have one more chance to close a business deal that better aligns with the company’s sweet spot. One of the pressing issues for EMS companies is the great deal of attention on sales and quoting software solutions and how to make them perform better. Chintan Sutaria, the founder and former CEO of CalcuQuote now working on other projects at OpenJar, explains.
Why I Finally Embraced Autorouting
07/03/2025 | Stephen V. Chavez, Siemens EDAHere is a common misconception held by those who don’t fully understand the PCB layout process or how to wield today’s high-level EDA tools: "All I need to do is push the autorouter button, let the computer route all the signal traces, and get the layout 100% routed. It’s a no-brainer. Anyone can do it. It should take less than a few hours.”
Target Condition: Are Autorouters Friend or Foe?
07/01/2025 | Kelly Dack -- Column: Target ConditionFor PCB designers, just hearing the word “autorouters” can trigger everything from eye rolls to heated debate. We all have stories—some painful, some comical—of boards gone sideways at the hands of an overzealous routing algorithm. But these tools aren’t going away, and frankly, they shouldn’t. Used wisely, they can save some project teams hours or even days. Used blindly, they can cost weeks. So, where do autorouting tools stand today, and is interactive routing the smarter path forward?
Magnalytix and Foresite to Host Technical Webinar on SIR Testing and Functional Reliability
06/26/2025 | MAGNALYTIXMagnalytix, in collaboration with Foresite Inc., is pleased to announce an upcoming one-hour Webinar Workshop titled “Comparing SIR IPC B-52 to Umpire 41 Functional & SIR Test Method.” This session will be held on July 24, 2025, and is open to professionals in electronics manufacturing, reliability engineering, and process development seeking insights into new testing standards for climatic reliability.