
- Plan your stack-up and microvia structure
- Choosing the right materials
- Signal integrity and controlled impedance in HDI
- Manufacturing considerations for higher yieldsimpedance in HDI




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buetow
in-chief
ears ago, ahead of a US election, I used this space to pen an open letter to the new president. I wrote that the race for office was heated and intense, but the winner should put aside any ill feelings and work toward the betterment of all Americans.
The column was timed to hit readers’ desks in November, just after the election results were announced. Magazine deadlines being what they were, of course, I wrote it in early October – more than four weeks prior to election day. In short, I submitted it to the printer having no clue who was actually going to win.
More than a few readers didn’t catch that little nuance, and they filled my inbox with screeds both positive and negative about the outcome, projecting their own biases on my musings and utterly missing the point I was trying to make about leadership.


PCBAA is a consortium of US-based companies that support initiatives to advance the US domestic production of microelectronics, specifically PCBs, and the materials that comprise the boards.
The organization values the market fairness and a level playing field on which US PCB manufacturers can compete against competitors subsidized by foreign governments.
Financial terms were not disclosed.
Based on the terms of the merger, which involved South Coast Circuits and Royal Flex Circuits, a subsidiary of Royal Circuit Solutions, the facility in Santa Ana, CA, will continue to conduct business as South Coast Circuits. Victor Hemingway, current president of Royal Flex Circuits, will become president of South Coast Circuits, reporting to Milan Shah, owner and cofounder of Royal Circuit.




The transaction, which has been unanimously approved by both companies’ boards, includes a “go-shop” period during which IEC will actively see alternative acquisition proposals, which the EMS could select over the Creation offer.
The transaction is expected to close by early October. Upon completion of the transaction, IEC will become a privately held company, and shares of IEC’s common stock will no longer be listed on any public market.
The transaction is expected to be finalized in the fourth quarter of 2021. Other terms have not been disclosed.
Shenzhen Huan Cheng has about 120 employees and annual revenues of almost SEK 100 million ($11.3 million).
Mycronic said screen printers account for 80% of Shenzhen Huan Cheng’s sales and placement machines the remaining 20%. China is the company’s dominant market, accounting for 95% of sales.
“With this acquisition we strengthen and broaden [our] product portfolio and are able to offer a more complete and attractive solution to our customers,” said Ivan Li, senior vice president, High Volume, Mycronic. (MB)
WASHINGTON – Face-to-face meetings have been scarce in the past year, but historically even rarer have been sessions between US electronics industry leaders and their counterparts in the US Department of Defense.
That made the July meeting even more meaningful for the large assembly of representatives who made time for the annual US Partnership for Assured Electronics meeting in Washington.
Some 55 USPAE members met with 12 representatives from the Department of Defense, including the Defense Microelectronics Cross-Functional Team, Research and Engineering, Industrial Base Analysis and Sustainment, the Defense Logistics Agency, and Roger Smith and Craig Herndon of the DoD Executive Agent.



Trends in the US electronics equipment market (shipments only)
Source: U.S. Department of Commerce Census Bureau, Aug. 3, 2021
For too many the disease itself has been devastating, from loss of life to the scores of friends, family and colleagues who fell seriously ill. No words can be said to ease the pain for those who have lost loved ones. For many others, the disease has cost them employment and caused dramatic changes in day-to-day lifestyles. For some, total despair. Indeed, the impact of Covid still can be seen and felt across the globe.
“The issue,” Mitchell notes, “is that America’s supply chains keep generating problems that frustrate consumers, threaten companies and undermine American competitiveness.”
He hits the nail on the head by calling for a more “holistic” approach and points out that while chips are important, they are just one piece of the puzzle. The printed circuit board, on the other hand, ties together all the components of electronics manufacturing, and that seems to be the greater domestic challenge.
Going beyond specifying alternating shape and route layers, the “greenest” PCB involves a minimum of etching. It’s intuitive that removing less material requires less time in the solvent tanks. Time is money, so that should be reason enough to have all layers biased toward copper fill.
Besides being easier on the equipment, copper-biased design will help maintain an even thickness across the entire board. While fabricators generally offer a +/-10% thickness tolerance, we often want a tighter distribution when it comes to the actual PCB thickness.
In this month’s column, I give kudos to our PCEA chapter liaison, who has been capturing the efforts of the PCEA to educate our members and our industry as a whole, then pass the mic to PCEA chairman Steph Chavez to provide some thoughts on taking charge of your career.
This month we highlight the work of PCEA’s Scott McCurdy, a tireless force for collaboration within the printed circuit engineering industry. Not only has McCurdy worked hard in the industry as director of sales & marketing for Freedom CAD Services in Orange County, CA, but for years he has worked as a leader in trade organizations specializing in educating their members.
We’ve written for months about how to control power delivery. While we have learned the effects of layout on the PDN, we haven’t yet focused on the other major influencing factor: the decoupling capacitor.
These simple, 2-pin devices perform two main tasks: resist a change in voltage across their pins and accumulate and store “charge” that can be delivered from those pins to maintain that voltage. In the world of digital design, this “decoupling” function is huge and is arguably why we do power integrity (PI) simulation in the first place. The power demands of a product’s components are largely defined by its features and performance requirements, which determine supply sizes. Between those lies the power delivery network (PDN), a subject we’ve intensely studied. Composed almost entirely from capacitors and the copper that connects it all together, the success or failure of a PDN is often determined in layout. In previous articles, we’ve written about “loop inductance” and how it impacts the capacitors’ ability to do their job. A solid understanding of cap differences and modeling will help identify loop inductance issues early to ensure a successful PDN.
Many things, including the electronics industry, have changed beyond recognition over the past 40 years or so. It’s all the more incredible how little the PCB has changed in its makeup since its inception, and thus fitting that PCD&F named its Hall of Fame after the printed circuit inventor, Paul Eisler. His radio, the first commercial product to contain a PCB, is on display at the Science Museum in London. It was made in 1945, containing a simple and straightforward PCB designed to implement point-to-point connections. Things have become more sophisticated, of course, as human nature provides both the push from engineers’ curiosity and the pull of market demands.
The main goal of early PCBs was to replace traditional soldered wire connections. This helped streamline assembly, reduce wiring errors, and increase reliability. The PCB’s arrival also facilitated automation of electronics product assembly. In early PCBs, the role of the substrate was barely considered, except to separate the conductors. Now, the substrate properties are the most important aspect where high signal frequencies are present. In other ways, it’s surprising how little has changed, as the constituent parts remain the same: a composite core, comprising a reinforcement and a resin binder, and copper conductors.
To say much has transpired in the past year and a half is the understatement of all understatements. When we published the findings of our last designers’ salary survey in May 2020, we were still in the early months of the Covid-19 pandemic, many of us in the initial stages of a lengthy quarantine we thought was temporary. We were unsure how the virus would affect the world in the short-term, let alone the long-term – with regard to the health of loved ones and the economy as a whole, to name two of countless concerns. It will be many years before we fully comprehend the enduring global impact of this unmitigated health crisis, but if this year’s survey is any indication, one thing that has remained consistent is the PCB design engineering profession.
The US unemployment rate in July 2020 was 10.2%, and as of July 2021, it was 5.4%, according to the US Department of Labor.1 More specifically, for engineering occupations, the unemployment rate as of Jun. 30, 2020, was 6.1%, and at Jun. 30 this year, it was only 3.4%, BLS says, and the computer systems design and related services sector added 100,000 jobs in June alone.1
In last month’s discussion of how electronics companies first began to use Blockchain technology to automate and simplify “high-friction” multiparty processes, we noted many of the earliest projects tended to focus on the relationship between a single “sponsor” company and its partners. In other cases, companies worked together as a consortium to solve a common problem. Quickly, however, electronics companies began to leverage applications originally developed for other industries, especially to leverage the “track and trace” capability originally developed for the food industry.
Basing a new blockchain network on functionality that has been developed and implemented for another network1, even in a completely different industry, lowers the cost of entry and simplifies the process of setting up that new network. That has turned out to be very important, since it also makes it easier to create a valid business case for the application.
A number of approaches to mitigate whisker growth have been pursued during the past 30 years, including additions of Pb, Bi, Au, Sb or Ge, or post-plating thermal treatments.4-8 These approaches mitigate whisker growth to varying degrees; however, none eliminates it. Over time, and under thermal-mechanical excursions, whiskers continue to grow.
Lean Six Sigma and Agility
How to identify opportunities for improvement and enable corrections before the product is at risk.
SigmaTron International’s Tijuana, Mexico, facility utilizes teams of Lean Six Sigma Green and Yellow Belts in its continuous improvement activities. They use a variety of core tools in that process.
As in, “We work in the AI space.”
Reminds one of workers beavering away in a corrugated shipping container with the letters “AI” stamped on the outside.
Or, “My career trajectory has symbiotic granularity with the ERP or IT or CRM space.”
What?
Are people who speak like this born this way or did they acquire this skill in school? For what purpose? Contrary evidence above notwithstanding, one must nevertheless cultivate the space between the ears.
Famously there is NASA, which spends its days laboring in the Space space. Or used to. Now commercial interests dare to boldly go where no one went before, spatially. NASA just writes the rules. Billionaires get the accolades.
We have presented live process defect clinics at exhibitions all over the world. Many of our Defect of the Month videos are available online at youtube.com/user/mrbobwillis. Find out how you can share our new series of Defect of the Month videos to explain some of the dos and don’ts with your customers via CIRCUITS ASSEMBLY: https://bit.ly/3mfunlF.












Reportedly acquires high-res images at high speed without image dragging. Performs oblique CT at 70° tilt; minimizes image distortion. Has 3.5sec/FOV and 9.6Mp detector with large FOV. Hybrid open tube enables high magnification and defect detection in 50[U]m. For double-sided and multilayer PCBs and chip packages.


Authors: Ning Yi, et al.
Abstract: 3-D freeform surface is of significant interest to wear-able devices on curvilinear skin/tissue surfaces or smart Internet of Things with sensors on 3-D objects. Here the authors present a new fabrication strategy that can directly print functional circuits either transient or long-lasting onto freeform surfaces by intense pulsed light-induced mass transfer of zinc nanoparticles (Zn NPs). The intense pulsed light can locally raise the tem-perature of Zn NPs to cause evaporation. Lamination of a kirigami-patterned soft semi-transparent polymer film with Zn NPs conforming to a 3-D surface results in condensation of Zn NPs to form conductive yet degradable Zn patterns onto a 3-D freeform surface for constructing transient electronics. Immersing the Zn patterns into a copper sulfate or silver nitrate solu-tion can further convert the transient device to a long-lasting device with copper or silver. Functional circuits with integrated sensors and a wireless communication component on 3-D glass beakers and seashells with complex surface geometries demonstrate the viability of this manufacturing strategy. (Materials Today, Aug. 5, 2021, www.sciencedirect.com/science/article/abs/pii/S136970212100225X)
