-
- News
- Books
Featured Books
- pcb007 Magazine
Latest Issues
Current IssueThe Growing Industry
In this issue of PCB007 Magazine, we talk with leading economic experts, advocacy specialists in Washington, D.C., and PCB company leadership to get a well-rounded picture of what’s happening in the industry today. Don’t miss it.
The Sustainability Issue
Sustainability is one of the most widely used terms in business today, especially for electronics and manufacturing but what does it mean to you? We explore the environmental, business, and economic impacts.
The Fabricator’s Guide to IPC APEX EXPO
This issue previews many of the important events taking place at this year's show and highlights some changes and opportunities. So, buckle up. We are counting down to IPC APEX EXPO 2024.
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - pcb007 Magazine
Alchemy in the Electronics Era
October 8, 2013 |Estimated reading time: 1 minute
The adage that the only constant is change always holds true in electronics. In some areas, like wire bonding inside chip packages, change doesn’t occur too quickly, but it inevitably comes.
Many chipmakers and packaging companies have used gold wire bonds for decades. But some are moving away from the precious metal.
Freescale is “aggressively moving” its automotive portfolio to copper, Glenn Daves, director, Packaging Solutions Development at Freescale, told me recently. That’s because the intermetallic bond between gold wires and the aluminum pads on chips isn’t very stable at high temperatures.
Other semiconductor companies have moved to copper, but automakers rarely want to be at the leading edge of emerging technologies. The high reliability requirements of the automotive market are a key driving factor behind Freescale’s move.
Making this aggressive shift isn’t without challenges. Copper is harder than gold, making it a bit tougher to work with. Also, it oxidizes and corrodes more readily, which isn’t the best thing in a car where chips are expected to last a decade or more. Apparently, those challenges are easier to solve than the task of resolving the CTE mismatch between gold and aluminum.
Using copper wires changes the cost model, which can impact other decisions in packaging. For example, some system designers may opt for package-on-package configurations which have been costly because users pay for two packages.
Any move that improves reliability while lowering cost is destined to see widespread usage. That’s one thing that isn’t going to change.