Printed Circuit Design & Fab Circuits Assembly September 2021 Cover
September 2021
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High-Density Interconnect Design Guide book
Before 12L and after 8L
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September 2021 • VOL. 38 • NO. 9
Printed Circuit Design and Fab Circuits Assembly logo
First Person
An antidote for business.
Mike Buetow
money matters
What employees need now.
Peter Bigelow
Buy local … if they can handle it.
Greg Papandrew
Tech Talk
Why evenly distribute copper on a PCB?
John Burkhert, Jr.
Identifying loop inductance issues.
Terry Jernberg
What role will optical interconnects and graphene play?
Alun Morgan
Learning the Gemba Walk.
Filemon Sagrero
I could see your point, if first you would remove your hat.
Robert Boguski
Uncovering delamination.
Bob Willis
September 2021 • VOL. 38 • NO. 9
Printed Circuit Design and Fab Circuits Assembly logo
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.
by Chelsey Drysdale
Printed Circuit Design & Fab Circuits Assembly September 2021 cover
Collaborative Tracking
As blockchain networks and capabilities mature, it has also become possible to integrate blockchain capabilities into other systems. Some of the most innovative ideas use blockchain to address security and privacy issues with applications based on IoT devices.
by Quentin B. Samelson
Electrochemical Migration
Over the decades, a number of approaches to mitigate whisker growth have been pursued. Researchers say a new method will finally accomplish the holy grail: eliminating whisker growth.
by Indranath Dutta, Ph.D.
IN the Digital Edition
Taking ownership of your continuing education and professional development.
Updates in silicon and electronics technology.
by Binghamton University
OEM-EMS Data Sharing
with Vincent Bedat
The Founding of STI Technology
with David Raby
Thermal Profiling
with Mark Waterman
Automating Electronics Development Workflows
with Gowtham Ramachandran
POSTMASTER: Send address changes to
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Caveat Lector
Portrait photo of a smiling Mike Buetow
A Pair of Antidotes to a Complex Environment

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.

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Around the World
PCDF People
Meredith LaBeau Headshot
Calumet Electronics promoted Meredith LaBeau, Ph.D to chief technology officer. She has a master’s and a Ph.D. in environmental engineering from Michigan Technological University and served eight years as the company’s director of process engineering and director of R&D.
Meredith LaBeau Headshot
Peters named Markus Wieler global business manager, responsible for OEM management. The industry veteran returns to Peters after a 13-year absence.
Around the World
New Consortium to Push US Domestic Electronics Production
WASHINGTON – A group of printed circuit board fabricators has established the Printed Circuit Board Association of America (PCBAA) amid rising geopolitical challenges faced by domestic microelectronics manufacturers in the US.

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.

Around the World
Royal Circuit Acquires South Coast Circuits
HOLLISTER, CA – Royal Circuit Solutions in August acquired South Coast Circuits, expanding its quickturn printed circuit board fabrication services. The deal marks the second acquisition Royal Circuit Solutions has completed as it continues to expand its PCB manufacturing operations and market reach.

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.

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Around the World
CA People
Steve Vecchiarelli Headshot
CalcuQuote said Steve Vecchiarelli is joining the company in an advisory capacity. He has 40 years of distribution experience, and will facilitate among the EMS industry, CalcuQuote, and customer needs for digital transformation.
Michael Ho Headshot
Cogiscan named Michael Ho director – business development. In his more than 30 years in electronics, Ho has been a software engineer for Universal Instruments and Nordson, among others.
Enics appointed Denis Laxague chief procurement officer.
Austin Jones Headshot
Mek (Marantz Electronics) has appointed Austin Jones sales engineer, North America. He has a bachelor’s from the University of Florida and worked for Leidos.
Jim Apfel Headshot
Naprotek appointed Jim Apfel senior vice president of business development. He has over 30 years’ experience in sales and business development with Spartronics, Benchmark Electronics, Realtek & SwitchCore, Diamond Multimedia, and Rockwell.
TT Electronics named Emma Darke group sustainability director.
Around the World
Creation Technologies to Buy IEC for $174M
NEWARK, NY – IEC Electronics and Creation Technologies have signed a definitive merger agreement under which Creation will acquire all outstanding shares of IEC for $15.35 per share in cash, making the deal worth approximately $174 million.

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.

Around the World
Mycronic to Acquire Chinese OEM
TABY, SWEDEN – Mycronic has signed an agreement to acquire Shenzhen Huan Cheng Xin Precision Manufacture, an OEM of screen printers and pick-and-place machines.

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)

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Around the World
USPAE Overcomes Covid, History to Get DoD Eyes on Electronics Sector

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.

Great designs
require more than
good tools.
You also have to know how to use them.
Box of tools used for circuit engineering
Trades from: Rick Hartley, Susy Webb, Lee Ritchey, Dan Beeker, Eric Bogatin, Mike Creeden, Gary Ferrari, and more! text
Online courses and webinars for the printed circuit engineering community.
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Market Watch
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Trends in the US electronics equipment market (shipments only)

Computers and electronics products
Storage devices
Other peripheral equipment
Nondefense communications equipment
Defense communications equipment
A/V equipment
Nondefense search and navigation equipment
Defense search and navigation equipment
Medical, measurement and control
rRevised. *Preliminary. 1Includes semiconductors. Seasonally adjusted.
Source: U.S. Department of Commerce Census Bureau, Aug. 3, 2021
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A Positive Message for Surviving a Pandemic
If ever employees deserved a big “Thank You,” now is it.
The world has been through the ringer over the past 18 months. Pandemics have a way of shaking things up in ways no one could possibly imagine. It’s sort of like being tossed into the wash cycle of a washing machine, being soaked from every possible direction, only to be rewarded by needing to survive the spin cycle! Covid-19 has brought nothing less. Regrettably, as summer turns to autumn, thanks to the Delta variant the end of this pandemic looks nowhere near.

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.

Board buying
US PCB Shops Should Look in the Mirror
Buyers will pay more for local products, if only manufacturers were easy to do business with.
In a recent qopinion piece in Roll Call, IPC president and CEOJohn Mitchell – addressing the Biden administration’s willingness to invest mightily in the global chip output – points out it will take this and much more to maintain the US electronics manufacturing industry’s competitiveness.

“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.

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Designer’s notebook
2 Approaches to Ensuring Even Copper Distribution
The best designs use the least amount of material possible.
Why evenly distribute copper on a PCB? Look at the material stackup as it alternates between conductor and dielectric material. The goal is to build a mirror image of copper weights as you work outward from the centerline.

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.

Taking Charge of Professional Development
Invest in yourself: You are your own best asset!

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.

PCEA Updates

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.

Jernberg pi
PDN Effectiveness: The Devil’s in the Decap Details
Understanding cap differences and modeling will help identify loop inductance issues early.

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.

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material gains
As Today’s PCBs Become Increasingly Advanced, the Original Principles Remain So Right
Could optical interconnects and graphene change the view?

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.

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In an Unpredictable World, PCB Design Engineering Stays Steady
PCD&F’s annual salary survey reflects the consistency and stability of the PCB design industry. by Chelsey Drysdale

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

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Collaborative Tracking
Blockchain Technology and Electronics Manufacturing: Getting Started
From secure data exchange to managing EoL parts, the applications are numerous. by Quentin B. Samelson

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.

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Tin Whiskers Eliminated by Slight Alloying with Indium
The indium additive relieves stresses that drive whisker growth. by Indranath Dutta, Ph.D.
Copper components in electronic packages (e.g., lead-frames, interconnects, integrated circuit leads and press-fit connector pins, to name a few) are often electroplated with tin (Sn) to prevent tarnishing and to facilitate subsequent soldering. With passage of time during storage or service, long whiskers grow from these tin coatings, causing electrical shorts between neighboring circuitry, posing serious reliability risks.1-3 This problem is particularly problematic in long-life applications, and failures have been reported in many arenas, including aerospace, nuclear power plants, automotive electronics, and military electronics systems, causing damages worth millions of dollars.

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.

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Lean Six Sigma and Agility

How to identify opportunities for improvement and enable corrections before the product is at risk.

The electronics manufacturing community is facing unprecedented challenges in 2021. Component supply and product demand are completely out of sync in many industries. Material constraints and transportation shortages are stretching lead-times even on committed orders. An economy flush with stimulus money and pent-up demand for products not available during much of 2020 has eliminated the ability of original equipment manufacturers (OEMs) to plan based on historical trends. In the middle is the EMS provider that sees material arriving later than planned, while at the same time experiencing unplanned increases in order volumes on many programs. Lean Six Sigma provides production teams the tools they need to identify issues, analyze potential improvements and implement changes that help keep production flowing on time even with changing production inputs.

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.

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State-of-the-Art Technology Flashes
Updates in silicon and electronics technology.
Ed.: This is a special feature courtesy of Binghamton University.
Integrated photonic circuits demonstrate ultralow loss. EPFL researchers have developed a technology that produces silicon nitride integrated photonic circuits with low optical losses and small footprints. Silicon nitride has been a material of choice for applications where low loss is critical, such as narrow-linewidth lasers, photonic delay lines, and those in nonlinear photonics. The team combined nanofabrication and material science based on the photonic Damascene process developed at EPFL. With this process, the team made integrated circuits of optical losses of 1dB/m, a record value for any nonlinear integrated photonic material. That low loss considerably reduces the power budget for building chip-scale optical frequency combs used in applications that include coherent optical transceivers, low-noise microwave synthesizers, lidar, neuromorphic computing and optical atomic clocks. (IEEC file #12282, Photonics Media, 5/6/21)
Seeing is Believing
Ratholes, Or You Will Never Recover This Time
If time is money, getting to The Point is invaluable.
Add “space” to the growing list of vandalized spoken English words.

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.”


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.

Defect of the Month
Lifted Solder Mask: Don’t Blame the Resist
When separation occurs, check the oven settings.
THIS MONTH WE look at printed circuit board delamination. As FIGURE 1 shows, delamination is barely visible on the surface of the board and confined to the area around through-holes and where the solder mask is cracking.
Most examples of delamination are visible and generated by high soldering temperatures or excess time for soldering. Although during soldering there are differences in the expansion rate of materials used in PCB manufacture, the board content can have a dramatic impact.

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 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:

PCB delamination, likely caused by excessive soldering temperatures
Figure 1. PCB delamination, likely caused by excessive soldering temperatures.
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Off The Shelf
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Machines Materials Tools Systems Software
RTO6 oscilloscope
Rohde RTO6
RTO6 oscilloscope features new user interface on 15.6″ HD touchscreen. Has 9.4 ENOB, update rate of one million waveforms per sec., and comprehensive toolset of analysis functions.
Rohde & Schwarz
InCAM Pro Flex CAM system
Frontline InCAM Pro Flex
InCAM Pro Flex CAM system optimizes wet processes to maximize yield using etch compensation tools. Delivers dedicated flex CAM tools from realistic FPC multi-zone models and automatic FPC panel creation to flex editing tools, analyses and DfMs. Automatic flex and rigid-flex board panelization with any angle rotation and PCB alignment for strip creation.
Ansys 2021 R2 closeup
Ansys 2021 R2
Ansys 2021 R2 increases data visibility and reuse for materials, digital twin components, electronic components and compliance initiatives. Productivity enhancements perform optical simulation meshing up to 20X faster and local meshing up to 100X faster. New chip-package-system (CPS) and PCB enhanced workflows with automation for IC-on-package and multi-zone PCBs with rigid-flex cables.
Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
i-Cube10 (YRH10) hybrid placer
Yamaha i-Cube10
i-Cube10 (YRH10) hybrid placer performs surface mount and die bonds (for wafer components). Bare chip mounting speed 10,800cph with mounting accuracy of ±15µm. Component recognition via head-mounted scan camera. 10-unit multi-nozzle mounting head. Feeder unit capacity twice that of previous models.
Yamaha Robotics SMT Section
X-eye 6300NTI inline 3-D CT AXI
SEC X-Eye 6300NTI
X-eye 6300NTI inline 3-D CT AXI features pulsed x-ray with hybrid open tube.

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.

E-cell scalable standard cell
Eutect E-cell
E-cell scalable standard cell customizes soldering automation. Combines new design with higher precision and greater cell modularity. Has higher rigidity than predecessors and enables higher precision in soldering process and automation. Machine frame, including doors and discs, is ESD-compatible. Control cabinet allows quick replacement of all electronics, including wiring. E-cells can be customized in width and length by grid dimension of 300mm.
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Technical Abstracts
In Case You Missed It
Circuit Fabrication
“Fabricating Functional Circuits on 3D Freeform Surfaces Via Intense Pulsed Light-Induced Zinc Mass Transfer”

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,

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Thanks for reading our September 2021 issue!