Printed Circuit Design & Fab Circuits Assembly February 2021 Cover
February 2021
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February 2021 • VOL. 38 • NO. 2
Printed Circuit Design and Fab Circuits Assembly logo
First Person
Has desktop ECAD reached its apex?
Mike Buetow
money matters
Overcoming Covid stagnation.
Peter Bigelow
Post-Covid sales and marketing.
Susan Mucha
Tech Talk
Drawing standards.
John Burkhert, Jr.
Flying high.
Alun Morgan
Batten down the crosshatches.
Nick Koop
Three common problems.
Clive Ashmore
Should the toe be exposed?
Bob Willis
February 2021 • VOL. 38 • NO. 2
Printed Circuit Design and Fab Circuits Assembly logo
As printed circuit boards get denser, with ever more parts, models, nets, and materials to use and track, and collaboration becomes a priority, can desktop tools keep pace? Our vendor panel says layout software needs to be more user-friendly, but more features are inevitable.
by Mike Buetow
Printed Circuit Design & Fab Circuits Assembly February 2021 cover
An investigation demonstrates the influence of QFN package construction on solder joint durability using thermal cycle testing (-55° to +125°C) in accordance with IPC-9701 for a SnPb soldering process. The results were used to create QFN package qualification protocols for producibility and solder joint integrity assessment.
by Tim Pearson, David Hillman, Ross Wilcoxon, Onel Valdez
Stencil Printing
Can a change of solvent in the printer improve SMT printing? A test compares IPA and a novel stencil cleaner on 0201 components.
by Timothy O’Neill and Logan Jelinske
As printed circuit boards get denser, with ever more parts, models, nets, and materials to use and track, and collaboration becomes a priority, can desktop tools keep pace? Our vendor panel says layout software needs to be more user-friendly, but more features are inevitable.
by Mike Buetow
Printed Circuit Design & Fab Circuits Assembly February 2021 cover
An investigation demonstrates the influence of QFN package construction on solder joint durability using thermal cycle testing (-55° to +125°C) in accordance with IPC-9701 for a SnPb soldering process. The results were used to create QFN package qualification protocols for producibility and solder joint integrity assessment.
by Tim Pearson, David Hillman, Ross Wilcoxon, Onel Valdez
Stencil Printing
Can a change of solvent in the printer improve SMT printing? A test compares IPA and a novel stencil cleaner on 0201 components.
by Timothy O’Neill and Logan Jelinske
IN the Digital Edition
What makes a design engineer?
Is the US Ready for Smart Manufacturing?
with Mike Buetow
The Changing Shape of the Mainstream ECAD Industry
with AJ Incorvaia
Transient Liquid Phase Sintering
with Matt Wrosch
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Caveat Lector
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Floating in the Mainstream

e speak so often of the maturing (“graying”) of the engineers and operators who work in the printed circuit industry, we sometimes overlook whether the same term applies to the companies that employ those individuals.

And yet that matzah ball is hanging out there, particularly when it comes to printed circuit design software.

The textbook definition of a mature market is when it has reached a “state of equilibrium.” This is characterized by “an absence of significant growth or a lack of innovation.”

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Around the World
PCDF People
Antti Ojala Headshot
Aspocomp promoted deputy CEO Antti Ojala to chief operating officer. He joined Aspocomp in 2003. He succeeds Jari Isoaho, who joined the fabricator in 1989.
Crane Aerospace named Dale Hanzelka senior engineering designer.
Eagle Electronics named Carl Schlemmer quality assurance manager.
Hari Pillai Headshot
Hari Pillai has rejoined Sanmina as president of Components Technology, the company’s printed circuit board and mechanical systems business unit. He previously spent 17 years with Sanmina in various leadership roles, including president and COO and executive vice president of its EMS division.
Around the World
CA People
CalcuQuote named Jani Leppälammi VP of global sales and Dirk Stender responsible for business development in Central Europe.
GEN3 named Chris Hunt, Ph.D., chief technology officer.
Inova named Reinaldo Drago industrial and supply chain manager.
Joe Pellot Headshot
Kurtz Ersa named Joe Pellot to its service team. His experience includes small engines mechanic.
Sandy Chew Headshot
MaRC Technologies hired Sandy Chew for sales in Northern California and Northern Nevada. She has a bachelor’s in mechanical engineering.
Around the World
Elite Material to Buy Arlon EMD
TAOYUAN, HEISN, TAIWAN – Elite Material Co. will acquire a 100% equity interest in EMD Specialty Materials, further consolidating the printed circuit laminates and removing yet another US domestic owner of a critical material. Elite will pay $28.73 million in cash for the company.

In a regulatory filing, Elite said it sought to establish a North American manufacturing base and expand to the US to meet long-term market demand.

Rancho Cucamonga, CA-based EMD makes specialty laminates and prepregs for PCBs used in the aerospace, defense and semiconductor industries. Known also as Arlon EMD, it has been owned by Critical Point Capital since its purchase from Rogers in 2015. (MB)

Around the World
Son of Founder Leads MBO of Circuits West
CHICAGO – A local consulting firm has partnered with Charles Anderson to acquire Circuits West for an undisclosed sum. Daniel P. O’Reilly and Co. will partner with Anderson, who is taking over for his father as CEO of Circuits West.

Circuits West designs and manufactures PCBs, specializing in the support and design of complex, dense and high-speed applications.

“I am excited to take over the company I’ve seen my father build over the past 25 years and lead it into the future,” said Anderson. “This investment will help Circuits West grow, add capabilities and modernize as a PCB manufacturer, while continuing to provide our clients with a world-class product and unparalleled customer service.”

DPO added, “We became intrigued by the bare board fab industry after learning that many of our private equity clients were investing in the space. When we dug into the industry and visited over a dozen board houses, it became clear there was a spectrum of quality, and that Circuits West was clearly near the top. Chuck did a great job of growing the company and continuing to invest in technology. With Charles’ energy and experience inside and outside the industry, we think we can do something really special. We will differentiate based on speed, quality and customer centricity that we think will be unrivaled in the relatively sleepy PCB space.” (CD)

Around the World
PE Firm Acquires Ohmega Technologies
CULVER CITY, CA – A private equity firm with $1.5 billion of committed capital in January acquired Ohmega Technologies, a manufacturer of embedded thin-film resistive materials. No other terms were disclosed.

In a press release, Arcline Investment Management said, “The addition of Ohmega perfectly aligns with our specialty electronic components platform growth strategy to assemble a portfolio of companies with world-class products and customer service. We are excited to work with this talented team to accelerate Ohmega’s growth, while maintaining the company’s unique culture and customer-first mindset.”

“We are very pleased with the acquisition of Ohmega by Arcline,” said Bruce Mahler, VP and general manager of Ohmega. “Our commitment to the long-term supply of OhmegaPly to our customers is enhanced with this acquisition. We’re also excited by the prospect of working with Arcline and Kevin Perhamus, the president of Arcline’s specialty electronic components group, and know Arcline’s commitment to investing in Ohmega and OhmegaPly will serve our customers well for many years to come.” (CD)

Around the World
US Congress Approves Funds for Pb-Free Electronics R&D
BANNOCKBURN, IL – The fiscal 2021 defense appropriations bill includes $10 million for research into the issues surrounding lead-free electronics in mission-critical applications. A number of trade groups including IPC had called for these funds to be included under the assertion that the high-rel sector has been slow to adopt lead-free materials, putting it at risk of falling behind best practices.

IPC said industry experts believe a five-year, $40 million investment in a public-private R&D program would yield more than $100 million in US defense savings per year and improve military readiness and overall innovation. Congress provided $5 million for such R&D in FY 2020.

Around the World
HIG Capital to Pay $171M for SMTC
TORONTO – SMTC has entered into a definitive agreement with an affiliate of H.I.G. Capital in which H.I.G. will acquire all outstanding shares of SMTC’s common stock for about $170.5 million.

SMTC’s board of directors has unanimously approved the acquisition and recommends stockholders adopt the agreement.

“Over the past three years, the team at SMTC has done an excellent job of transforming the company into a global leader among midsize providers of end-to-end electronics manufacturing services by offering superior supply chain management and proactive services and solutions to an expanding base of customers,” said Ed Smith, president and CEO, SMTC. “Partnering with H.I.G. will enable us to accelerate our growth through continued investment in our customers, capabilities, and footprint.

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Around the World
CA Briefs
Absolute EMS has invested in three Hanwha Techwin Automation HM520 modular mounters and a nitrogen oven.

ACC Electronix installed two CyberOptics SQ3000 3-D SPI/AOIs.

Akyumen Industries will invest $100 million in a new facility to make 5G smartphones in Gary, IN.

Apple suspended new business to Wistron in Narasapur, India, in the wake of worker riots in late December. Up to NT$200 million (US$7.1 million) in damage was caused. In response, Wistron fired the head of the factory.

Apple plans to produce up to 96 million iPhones for the first half of 2021, a nearly 30% year-on-year increase, but industrywide shortages of key components could threaten that target.

ASE, Chunghwa Telecom and Qualcomm unveiled a 5G smart factory in Taiwan.

Baidu, the Chinese search giant, is reportedly considering making its own electric vehicles and has held talks with automakers about the possibility.

Around the World
PE Firm Behind Spartronics Acquires Primus
WILLIAMSPORT, PA – New York-based One Equity Partners, a middle market private equity firm, has purchased Primus Technologies, an EMS firm based in Williamsport, PA, with annual revenues over $100 million. Financial terms of the transaction were not disclosed.

Last July, OEP bought the EMS assets of Sparton Corp., which has since been renamed Spartronics. The combined companies will have annual revenues of around $420 million, a source with knowledge of the transaction told CIRCUITS ASSEMBLY.

Around the World
AEM Holdings Proposes Acquisition of CEI for $75M
SINGAPORE – Electronics manufacturing company AEM Holdings has launched a S$99.7 million (US$75.2 million) bid for contract manufacturer CEI. AEM plans to delist CEI from the Singapore Exchange and take it private.

AEM is offering S$1.15 in cash, or a mix of cash and new AEM shares, for each ordinary share in mainboard-listed CEI.

CEI shareholders can opt to accept the offer for either 85% cash and 15% new shares, or 70% cash and 30% new shares at an issue price of S$3.55 for each new share in AEM.

Founded in 1999, CEI has annual revenues of about $100 million primarily from customers in the industrial equipment market. It operates sites in Singapore, Indonesia and Vietnam. (CD)

Around the World
Intervala to Expand at New Site in PA
PITTSBURGH – Intervala has signed a long-term lease finalizing the relocation of its corporate headquarters and EMS manufacturing operation in Westmoreland County, PA.

With the relocation, the company continues to reside in the Greater Pittsburgh area and gains more square footage in anticipation of future growth. Intervala finalized the five-year lease for the 217,000 sq. ft. space, including several extension options.

Market Watch
Inventory Tightens

Trends in the U.S. 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, Jan. 6, 2021
Is Covid Stagnating Your Workplace? Here’s What to Do
Dealing with the emotional toll of the pandemic.
Stagnation is a devastating condition for any business. No enterprise chooses to be stagnant, and rarely does anyone within notice when inertia begins. Still, the effect can launch a downward spiral that can cripple companies, even in the most dynamic industries.

Stagnation has many causes, which can take a long time to do damage. Most common are simple things, such as when a company slows or stops development of new products or capabilities, or when it takes existing customers for granted while not working to develop new ones. Most common is when management stops investing in needed equipment or workers to make the bottom line look better, quarter after quarter. Each of these decisions are made, consciously or not, by management. And while the intentions may have been good, over time they become the root cause of stagnation and can bring a vibrant company to its knees.

Sales and Marketing in the Transition to Post-Covid-19 Normal
Traditional materials such as whitepapers and articles are solid lead generators.

What a difference a year makes. As I write this, three Covid-19 vaccines are approved and are in distribution to healthcare workers and nursing homes. By the time this is printed, it’s likely the next tier of eligible recipients will be able to get a shot at a pharmacy or their doctor. The speed of development, manufacturing, testing and deployment is unparalleled. The teams involved in this have set the stage for a return to normalcy. Yet it is likely Covid-19 will have a global impact on business travel and selling processes for most of 2021, because it will take time for herd immunity to develop. So, what should sales and marketing teams in the electronics manufacturing services (EMS) industry expect as we transition back to normal?

The need for speed. OEMs discovered some EMS companies could cut new product introduction (NPI) time significantly during 2020. The bar will likely stay raised, both because it provides competitive advantage and because unanticipated variations in demand require it. Companies able to exploit their success in this area will likely see additional new business.

designer’s notebook
Why Do We Have to Follow Drawing Standards?
They play an outsized role in continuous improvement.
Time was creating drawings meant using paper and a pencil. Can you imagine? The main variable was the type of so-called lead in the pencil. Even in those primitive times, it was necessary to agree on an overall language. The particulars that allowed the community to get its message across were determined by standards. Standards, in turn, were driven by the requirements of the equipment that archived and reproduced the drawings.

One of those pieces of equipment was microfilm. You might recall microfilm stores many drawings in a small space. Bringing those tiny pictures back to human-readable sizes would lose some of the sharpness of the data. Standards were set up so we could still make out the images and data with no doubt about what we saw.

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Oh, That Radical PCB Engineering Conspiracy Theory
Applying sound science to circuit board design through test.
In this month’s column, I share a few terms I’ve been contemplating lately, which I have been trying to put in the context of the role of the PCEA within the electronics industry. Next, I hand it off to PCEA Chairman Steph Chavez for some inspiration for the fresh start of the year. And finally, I provide a list of coming events.
PCEA Updates
You may have noticed the use of three concepts mentioned extensively in 2020: “believe the science and data,” “speak truth to power,” and consider “systemic” causes for problems.

These concepts were associated with some particularly challenging, if not nasty, displays of societal failure in 2020. It has been easy for us to see how, in an agitated and perhaps desperate social climate, a time-consuming, methodical approach to collecting data and applying them to science can give way to convenient conspiracy theory. Speaking truth to power got some people fired overnight. The term systemic was used to point to long-term causes for some particularly blatant failures of a society to prepare people for success.

material gains
Zero-Emission Aviation Promises Better Services and Cleaner Skies
Are low-loss flex circuit materials an enabler?
Saab may have been first to bring aerospace technologies overtly into the automotive world when it introduced the aerodynamically styled 92 in 1948. The idea proved popular and effective, setting a trend that has made technologies such as infrared vision, radar and heads-up displays common features in today’s vehicles.

The flow of technology and know-how may soon be seen in reverse, as the aviation industry seeks to clean up its environmental credentials. In my last column, I mentioned Airbus’ recent flying achievements with fully electric planes. The company is also experimenting with hybrid platforms powered by a combination of lithium-ion batteries and a range-extending combustion engine, and recently unveiled several new hydrogen-powered concepts.

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The Flexperts
Why Do Some Flex Circuits Have Hatch Patterns in the Plane Layers?
Crosshatches help meet target impedance values and improve flexibility
A crosshatch or mesh pattern is often seen in the copper plane of a flex circuit. It will look something like FIGURE 1.
Figure 1. A crosshatch or mesh pattern in the copper plane of a flex circuit.
The most common hatch pattern is a simple mesh of conductors perpendicular to each other and rotated 45° relative to the signal pattern. Some use elongated diamond shapes or circular openings. Each accomplishes the same thing. Keep in mind most impedance tools model only the perpendicular square opening pattern.
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Desktop Tools to Remain a Fixture
Despite channel changes, the major EDA vendors say user demand makes mainstream tools worth their continued support.
What is the future of the mainstream PCB CAD market? As printed circuit boards get denser, with ever more parts, models, nets, and materials to use and track, and organizations emphasize collaboration across locations and technical domains, can standard tools keep pace? Do the vendors have the pockets and desire to continue developing multiple solutions to common problems? Or will the market dissect into open-source and enterprise platforms with a vacancy in the middle?

In pursuit of an answer to these and other questions, PCD&F in January reached out by email and phone to the top vendors of ECAD tools. We heard back from all but one. Their perspectives are aggregated here, with some edits for length and clarity.

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The Influence of QFN Package Construction on Solder Joint Durability
A case study characterizes solder joint integrity of different BTC constructions in an accelerated lifetime test. by TIM PEARSON, DAVID HILLMAN, ROSS WILCOXON and ONEL VALDEZ
The electronics industry has extensively documented the influence of component construction on solder joint integrity. Materials used in the construction of a component package body result in a composite coefficient of thermal expansion (CTE) for the package that may result in the degradation of the package solder joint integrity. The industry discovered in the 2000s the construction design of ball grid array (BGA) packages had a significant influence on solder joint integrity. BGA solder balls located directly beneath and sometimes adjacent to the package internal die-to-package transition region (i.e., the die shadow region) failed first due to the CTE mismatch forces.1-3 Extensive finite element modeling, combined with use environment experiences and test data4-5 resulted in package redesign protocols that for the most part eliminated die shadow solder ball failure in BGA packages.

This paper documents an investigation of the impact of bottom-terminated component (BTC) package construction on solder joint integrity using thermal cycle testing (-55° to +125°C) in accordance with IPC-9701.

Diagram and list of test vehicle construction details
FIGURE 1. Test vehicle construction details.
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Stencil Printing
Effect of Under-stencil Wipe Chemistry on Print Performance
Can a change of solvent in the printer improve SMT printing?
Any engineer will testify lab testing may not correlate with field results. Laboratory data are developed under ideal conditions to generate accurate and repeatable data, whereas a production setting introduces variables not reproducible in the lab environment.

In this report, AIM’s application lab approximated a production environment in a multi-hour printing test to quantify the effect of under-stencil wipe solvent on solder paste performance. This experiment compared isopropyl alcohol (IPA) and a novel stencil cleaner. IPA is not recommended as an in-process stencil cleaner, but is often used because it is inexpensive, effective and readily available. However, IPA is not a constituent of solder pastes and can therefore cause changes to paste that will negatively impact performance.

The Most Prevalent Printing Defects and How to Solve Them
Our expert troubleshoots three common problems.
Regular readers of this column and certainly most process engineers are acutely aware of the multitude of problems that can arise in the stencil printing process if it is not optimized. With numerous inputs and variables – shown in the fishbone diagram (FIGURE 1) – the number of things that can go wrong are many, but that shouldn’t portend that things will go wrong. Stencil printing, as I’ve said before, can be simplified into having the right amount of material at the right time in the right place. Therefore, too little or too much material, or improper timing or location, can result in defects. On the flip side, knowing how to avoid or correct the most common printing defects can mitigate against proliferation and secure successful results. This month, we look at the basics, discuss the top three printing-related defects and the problems they cause, and share advice on how to resolve them. (Caveat: There are multiple potential causes and cures; here, we discuss the most common.)
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defect of the month
Solder Toe Fillets or Not?
Should the toe be exposed?
This month we look at solder toe fillets. A solder toe fillet is part of the solder joint visible on most gullwing terminations. These are typically seen on SOIC, QFP and surface mount connectors. FIGURE 1 shows satisfactory joints with no or limited toe fillets.

Providing solderability on the tip of the pins is good: A solder joint will form on the pad after reflow. No criteria exist for a wettable surface on the tips of the pins. Often the protective plating is removed or smeared when the leads are cut and formed; they may or may not be solderable or last long. The issue is similar with quad flat no-lead (QFNs) and why there aren’t side joints on these packages. The base metal is exposed or the plating smeared on the pins.

Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
a machine that performs high-throughput roll-to-roll direct imaging of flex circuits
Orbotech Infinitum
Infinitum performs high-throughput roll-to-roll direct imaging of flex circuits. Employs novel drum direct imaging for material handling and high-speed imaging. Compatible with range of resists and processes. Is capable of 10/15µm lines and spaces with +/-10µm accuracy. Handles rolls up to 50m long, and can process up to 2,700m/24 hr.
flexible printed circuit connector
Hirose FH72
FH72 flexible printed circuit connector has single-action lock for portable electronic applications. Has height of 0.9mm and 0.3mm pitch. Suitable for consumer devices, gaming, industrial, medical and wearables. Rugged design with low FPC insertion force and high FPC retention force that is 4x typical non-ZIF design.
Hirose Electric
high-current terminal shunt resistors
Stackpole HCSK4026
HCSK4026 high-current terminal shunt resistors now include 0.7mΩ and 3 mΩ resistance values. Can be used in wider range of precision power control applications where efficient sensing is critical. Applications include power management, power modules, battery charging, frequency converters, hybrid power current sensing, engine and motor controls, and PC graphics and motherboards.
Stackpole Electronics
Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
inspection system featuring tiny optical probe
Inspectis Sideview
Sideview BGA inspection system features tiny optical probe with built-in high-power lighting and 90° viewing angle. Produces high-resolution images of low-clearance areas beneath BGAs, µBGAs, CSP, CGA and flip-chip packages, with as low as 40µm standoff. Variable focus capability of optics images from first to up to 20 rows of BGA solder bumps with electronically dimmable fiber brush light as background illumination.
machine that measures large components or multiple small components
Vision Engineering LVC200
LVC200 automated video measurement measures large components or multiple small components. Offers choice of measuring capacities and automated movement in all three axes. Nonstop measurement routines possible through programs that can have magnification changes built in. Multiple components can be loaded onto stage and measured in single program. Plus models have up to 700x magnification range.
Vision Engineering
Omnibus data logger
AHMT Omnibus
Omnibus data logger wirelessly analyzes settings of soldering ovens and conveyor belts and returns the measured values live. Detects faulty settings, necessary maintenance work and possible production errors at an early stage. Modular system. Handles operating temp. up to 300°C. For reflow, vacuum, conduction soldering (hot plate), selective and wave soldering, plus coating, curing and drying.
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Technical Abstracts
In Case You Missed It
3-D Printing
“Inflight Fiber Printing Toward Array and 3-D Optoelectronic and Sensing Architectures”

Authors: Wenyu Wang, et al.

Abstract: Scalability and device integration have been prevailing issues limiting the ability to harness the potential of small-diameter conducting fibers. The authors report inflight fiber printing (iFP), a one-step process that integrates conducting fiber production and fiber-to-circuit connection. Inorganic (silver) or organic {PEDOT:PSS [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate]} fibers with 1- to 3-µm diameters are fabricated, with the fiber arrays exhibiting more than 95% transmittance (350 to 750nm). The high surface area-to-volume ratio, permissiveness, and transparency of the fiber arrays were exploited to construct sensing and optoelectronic architectures. The authors show the PEDOT:PSS fibers as a cell-interfaced impedimetric sensor, a 3-D moisture flow sensor, and noncontact, wearable/portable respiratory sensors. The capability to design suspended fibers, networks of homo cross-junctions and hetero cross-junctions, and coupling iFP fibers with 3-D-printed parts paves the way to additive manufacturing of fiber-based 3-D devices with multi-latitude functions and superior spatiotemporal resolution, beyond conventional film-based device architectures. (Science Advances, September 2020,

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Thanks for reading our February 2021 issue!