Trouble in Your Tank: Causes of Plating Voids, Pre-electroless Copper
Dan’s Biz Bookshelf: ‘Growth Hacker Marketing’
Happy’s Tech Talk #38: Novel Metallization for UHDI
Thin PCBs for Smart Phones: Technology and Reliability Considerations
November 19, 2014 |Estimated reading time: 1 minute
Abstract
The next generation of smartphones will demand very thin multilayer boards to reduce product thickness again. This paper shows three different manufacturing approaches which can be used for very thin, any-layer build-ups. The technological approaches are compared on reliability level—the any-layer copper filled microvia technology which is to be considered as state-of-the-art technology for high-end phones and the ALIVH-C/G technology that is well established in Japan.
A test vehicle design featuring test coupons for comprehensive reliability test series has been defined as target application for investigation. The applied test vehicle build-ups comprise an eight-layer build-up with total board thickness below 500 µm. The first test vehicle is based on an any-layer HDI build-up including copper filled stacked microvia structures, the second test vehicle features a 1+6+1 ALIVH-C build-up comprising an outer HDI prepreg layer, while the third test vehicle is built in ALIVH-G technology featuring a full ALIVH build-up.
The influence of the applied manufacturing technology on the reliability performance of thin PCBs is evaluated based on these three test vehicle build-ups.
To cover the behavior during SMD component assembly the produced samples are subjected to reflow sensitivity testing applying a lead-free reflow profile with a peak temperature of +260ºC. Failure occurrence and the observed failure modes are evaluated and compared.
In parallel, a temperature cycling test is conducted on the test vehicles in a temperature range between -40ºC and +125ºC to evaluate the thermo mechanical reliability of the test vehicles with regard to the manufacturing technology.
To characterize the reliability aspects influenced by electrochemical migration phenomenon the different samples are subjected to a HAST test at +130ºC with 85% humidity level.
The results obtained from reliability testing are summarized and compared within this paper. The identified relations between manufacturing technology and the reliability performance of the test vehicles are shown; strengths as well as weaknesses of the applied any-layer technologies are identified and summarized.
Read the full article here.
Editor's Note: This article originally appeared in the October issue of The PCB Magazine.
Share on:
Suggested Items
New Issue of Design007 Magazine: Are Your Data Packages Less Than Ideal?
05/09/2025 | I-Connect007 Editorial TeamWhy is it so difficult to create the ideal data package? Many of these simple errors can be alleviated by paying attention to detail—and knowing what issues to look out for. So, this month, our experts weigh in on the best practices for creating the ideal data package for your design.
RF PCB Design Tips and Tricks
05/08/2025 | Cherie Litson, EPTAC MIT CID/CID+There are many great books, videos, and information online about designing PCBs for RF circuits. A few of my favorite RF sources are Hans Rosenberg, Stephen Chavez, and Rick Hartley, but there are many more. These PCB design engineers have a very good perspective on what it takes to take an RF design from schematic concept to PCB layout.
The Right Blend: Mixed Wireless Technologies
05/08/2025 | Kirsten Zima, Siemens EDAA common trend recently is to employ as many radios as possible on a single PCB. With the increase of wireless standards and the downscaling of PCB size, it can be difficult to know what the most critical design parameters are to focus on. In this article, we’ll discuss the most important considerations to make when designing with mixed wireless technologies, such as Bluetooth, GPS, and Wi-Fi, on a single PCB. These considerations include antennas, frequencies, FCC compliance, shielding, and layout with and without transition vias.
Navigating Global Manufacturing in an Era of Uncertainty
05/07/2025 | Philip Stoten, ScoopThe EMS industry faces unprecedented challenges as global trade tensions rise and tariff announcements create market uncertainty. In an overview of IPC Europe’s podcast, MADE IN EUROPE, industry experts from GPV and Zollner examine how these developments impact our businesses and customers, and what strategies will prevail in this new landscape.
Voices of the Industry: Alpha Circuit
05/06/2025 | Marcy LaRont, PCB007 MagazinePrashant Patel, founder and president of Alpha Circuit, takes a pragmatic approach to doing business: “Commerce always wins out,” he says. How will potential tariffs and shifts in the economy affect PCB manufacturing? Prashant offers sound advice.