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october 2021 • VOL. 38 • NO. 10
Printed Circuit Design and Fab Circuits Assembly logo
First Person
6
Making progress.
Mike Buetow
money matters
14
Imagine this image.
Peter Bigelow
16
The upside of bad news.
Susan Mucha
Tech Talk
18
When to use microvias.
John Burkhert, Jr.
22
PDN process oversight.
Terry Jernberg
25
More from less.
Alun Morgan
26
Unmasked.
Nick Koop
42
All hail the squeegee!
Clive Ashmore
44
A close look at microsections.
Bob Willis
Departments
october 2021 • VOL. 38 • NO. 10
Printed Circuit Design and Fab Circuits Assembly logo
Features
28
Advanced Packages
Is it worthwhile to design printed circuit boards with the smallest component package available today: the 008004? And how do you do it correctly?
by Michael Schneider
Printed Circuit Design & Fab Circuits Assembly October 2021 cover
31
Solder Materials
PCB surface finishes have no effect on shear strength of either alloy before or after thermal cycling.
by Pritha Choudhury, Ph.D., Morgana Ribas, Ph.D., John Fudala and Mitch Holtzer
37
Industry 4.0
Integration of automated optical inspection with an MES can ensure the data generated from detected defects are shared throughout the factory. The new CFX standard might be the solution to permit an MES to completely control the AOI operation.
by Matthew Fischer, Ranko Vujosevic, Ph.D., and Loc Do
IN the Digital Edition
PCEA does its first trade show.
by KELLY DACK
by PRIYANKA DOBRIYAL, PH.D.
ON PCB CHAT (pcbchat.com)
The History of Zestron
with Dr. Harald Wack
Lean Manufacturing
with Patrick Stimpert
EMS in Colombia
with Jorge Cardona
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Caveat Lector
Portrait photo of a smiling Mike Buetow
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buetow
editor-
in-chief
Making Progress
I

once heard the actor Tom Hanks – probably the first time he’s been referenced in these pages – describe a brain game he plays with friends. The challenge, he explained, is to define a concept in as few words as possible. The example he offered was “time,” which he characterized as “progress.”

Now, it’s easy to find physical and historical examples that disprove Mr. Hanks’ conceptualization.

More than a few readers probably studied physics in high school or college. Einstein’s relativity theory of time, of course, states that time changes depending on your frame of reference, and that the faster you travel the slower time moves.

And the ecologist and author Jared Diamond argues that there’s evidence some populations such as Austronesians began to use metal tools – an obvious improvement over rocks and bare hands – only to later shed them.

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Around the World
PCDF People
Altair named Harry Kennedy technical specialist, electronic system design.
Out of the Box Manufacturing named Mark Thompson engineering manager.
PCDF Briefs
Additive Circuits Technologies completed its acquisition of Bench 2 Bench Technologies, a Fullerton, CA-based flexible circuit board manufacturer.

AGC Multi Material America named Tritek Circuit Products West Coast distributor.

Around the World
Pending Defense Appropriations Bill Includes Anti-China Provision
WASHINGTON, DC – The US House Armed Services Committee in September voted overwhelmingly in favor of the National Defense Authorization Act (NDAA) for Fiscal Year 2022, which includes tighter language over sourcing of printed circuit boards from adversarial nations.

The committee passed the annual defense appropriations bill, also known as H.R. 4350, by a 57-2 margin on Sept. 2. The $744 billion bill includes a provision for improved printed circuit board supply chains. It tightens restrictions on the acquisition of certain printed circuit boards for which supply chains may be susceptible to interference by the Chinese government and directs the Secretary of Defense to investigate whether to extend the prohibition to other uses.

“The Secretary [of Defense] shall use the report to determine whether any systems (other than defense security systems (as defined in section 2533d(c) of title 10, United States 16 Code)) or other types of printed circuit boards should be subject to the prohibition in section 18 2533d(a) of title 10, United States Code.

“These provisions will reduce supply chain risk in critical defense systems, and will encourage development of reliable, effective, and efficient sources of printed circuit board technology in the United States and its allies and partners,” the NDAA summary says. (MB)

Around the World
Consortium Investigates Warpage, Die Shift in Large-Format Reconfigured Panels
BERLIN – The second incarnation of a panel level packaging consortium, PLC 2.0, investigated warpage and die shift in large-format reconfigured panels (18″ x 24″), and considerable progress has been made toward understanding the root causes.
Figure 1. First results of PLC 2.0: Detailed view of a fully populated panel with embedded chips.
Figure 1. First results of PLC 2.0: Detailed view of a fully populated panel with embedded chips.
The first incarnation of Panel Level Packaging Consortium (2016-19) consisted of 17 international partners from industry and focused on the entire process chain in panel-level packaging: assembly, molding, wiring, cost modeling and standardization.

With the second consortium, the focus has shifted to die placement and embedding technology for ultra-fine-line wiring down to 2µm lines and space with a potential move to 1µm. As such, migration effects and ways to exploit the migration limits of fine line wiring have become areas of interest for the consortium, whose members include Amkor, ASM, AT&S, Atotech, Corning, DuPont, Schmoll, and Showa Denko, among others.

Around the World
CA People
Axiom Electronics promoted Rob Rowland to director of engineering.
Honeywell named Brian Lau director of business development.
HP named Hames McCall chief sustainability officer.
Javad EMS announced Arturo Castillo as business development manager.
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Kitron named Kristoffer Asklöv chief operating officer. He has more than 20 years’ experience in electronics production and an executive MBA in leadership and management.
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Libra Industries named Joe Anderson senior director of business development. An established global sales executive with more than 20 years in EMS, he served for 12 years as director of business development for TT Electronics.
Wade Henderson Headshot
Libra also named Wade Henderson vice president of business development. He started in electronics in 1990 as an engineering manager at DSC Communications, and has a bachelor’s in engineering and an MBA.
Segue Manufacturing Services announced James Wright as vice president of engineering and quality.
Parallel Wireless named Jon Saunders senior director of operations and supply chain.
Tempo Automation named Mattias Cedergren chief manufacturing officer.
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Around the World
Creation Builds with Computrol Addition
BOSTON, MA – After a long pause, Creation Technologies is back on the acquisition trail. The EMS company on Sept. 9 announced its second acquisition of the fall, acquiring Meridian, ID-based Computrol for an undisclosed amount.

In August, Creation announced plans to acquire IEC later this year.

“The addition of the Computrol team will significantly enhance our ability to serve customers. Computrol shares our values of providing exceptional customer service and outstanding quality,” said Stephen P. DeFalco, chairman and CEO, Creation Technologies.

Creation said the acquisition expands its capabilities in the medium volume/high reliability segment servicing Aerospace & Defense, Medical, and Tech Industrial customers. It adds locations in Meridian, and Westminster, CO, offering seven highly automated state-of-the-art SMT lines and over 100,000 square feet of production space.

As a result of the acquisition, Creation will establish a New Product Realization Center by moving its design services team from Golden, CO, to Computrol’s Westminster site. The center will feature Creation’s Launch with Excellence to Advanced Production (LEAP), a stage gate NPI process that improves the ability to rapidly launch new designs. (MB)

Around the World
Spartronics Acquires Inovar
WILLIAMSPORT, PA – Spartronics has acquired fellow EMS Inovar for an undisclosed amount. This is Spartronics’ second acquisition in the past nine months.

Inovar provides engineering, manufacturing, product assemblies and aftermarket services used by OEMs in the aerospace, defense, medical and industrial markets. It has estimated revenues between $125 million and $150 million.

“Inovar is the Rocky Mountain leader for full-service Tier 3 electronic manufacturing services,” said Paul Fraipont, president and CEO, Spartronics. “It focuses on the same core market verticals as Spartronics, with a very strong position in aerospace and defense. Acquiring Inovar sharpens our focus on those core market verticals. Inovar’s attractive near-shore footprint in Tecate, Mexico, complements our unique and growing offshore capability in Vietnam.”

“Inovar and Spartronics have deeply aligned values, commitments and ideals toward customers and employees,” said Blake Kirby, founder, Inovar. “This acquisition will provide world-class resources and a broader geographic footprint for customers, while creating opportunities for the team.” (CD)

Around the World
Neways Agrees to Infestos’ Acquisition Bid Pending Shareholder Vote
SON, THE NETHERLANDS – Neways has agreed to be acquired by an investment firm in an all-cash deal worth approximately €177.5 million.

Since late June, Infestos has had a standing offer of €14.55 in cash for all issued and outstanding ordinary shares in Neways, a premium of about 33.5% over Neways’ closing price on Apr. 29, and a premium of 65% over the average daily volume weighted price for the six months prior to that date.

Neways’ management board and supervisory board said in a statement they fully support the transaction and unanimously recommend the deal to shareholders. A shareholder vote will take place this month.

The offer is subject to certain conditions, including a minimum acceptance level of 60% of the shares, or such lower amount as determined by Infestos in consultation with the boards but with a minimum of 50.01% of the shares.

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Around the World
NCMS Publishes Report Analyzing Digital PLM Implementation
ANN ARBOR, MI — The National Center for Manufacturing Sciences published a report featuring analysis for successful digital product lifecycle management implementation, covering insight from years of collaborating with government and industry partners to determine a more cost-effective way to launch specific PLM processes, which can enable small- and medium-sized companies to make the leap. The nonprofit manufacturing consortium has developed a commercial off-the-shelf solution: PLM-in-a-Box–Early Acquisition Edition, which focuses on the needs of the government partners.

Through a series of test projects, NCMS has worked with government partners who wanted their logistics and engineering communities to have a standardized, integrated method of accessing product lifecycle information for their larger assets. They wanted to focus on developing a PLM solution that could manage configuration control and synchronize successive changes in PLI.

Market Watch
EDITED by CHELSEY DRYSDALE
Hot Takes
  • Smartphone shipments are expected to grow 7.4% in 2021, reaching 1.37 billion units, followed by 3.4% growth in 2022 and 2023, respectively. (IDC)
  • The US PC market grew 17% year-over-year in the second quarter, with total shipments of desktops, notebooks, tablets and workstations reaching 37 million units. (Canalys)
  • Worldwide PC shipments are expected to grow 14% to 347 million units in 2021. Tablet shipments are expected to grow 3.4%. (IDC)
  • DRAM suppliers’ second quarter revenue reached $24.1 billion, up 26% sequentially. (TrendForce)
  • Global wearables shipments grew 32% year-over-year as volumes reached 114.2 million during the second quarter. (IDC)
ROI
Redefining Craftsmanship
Today’s builders have data analytics skills that match their manual dexterity.
Sometimes you see things a hundred times or more before it hits you the image presented does not match the message it intended to convey.

Case in point: A common television ad of late for a fairly high-tech product. The message was about the quality that goes into “making” these devices. So far, so good. But the ad fades to a man decked in a flannel shirt, blue jeans and the obligatory well-groomed beard, eyeing with pride some woodworking project. I get it: Pride in workmanship. The skilled craftsman produces a fine item. The message and imagery are ageless. One problem, though: That’s not how it goes!

It’s been decades since I purchased an item that is not the result of vigorous, data-driven engineering, followed by a slew of process, manufacturing, quality, and even finance folks obsessed with the analyses, measurement, inspection and costing of every piece of anything that gets even close to the product. While I’d like to think some flannel-shirted woodworker hand-built a device, the reality is data, and more data, and a little data on top of that, are what it takes to turn a concept into a successful product.

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FOCUS ON BUSINESS
Making a Good Business Case When Delivering Bad News
The wrong attitude can send customers shopping for a new EMS provider.
I frequently say program management is the most difficult job in the electronics manufacturing services (EMS) industry. Program managers play a dual role of their customers’ champions within their organization and their employer’s enforcer to ensure each account hits its revenue and profit targets. I see great similarities between PMs and airline gate agents, for whom getting customers where they need to go is often impeded by forces outside an agent’s control.

If we use that gate agent analogy to describe the program manager’s dilemma in today’s chaotic materials situation, the plane is running four hours late; the passengers who were loaded an hour ago now need to be told the crew needs to deplane because they’ve exceeded their legal flight time limits, and there are no alternate flights because a bad storm has shut down the entire East Coast. The state of imbalance between supply and demand in today’s materials market is so bad, the issue isn’t whether customers will be disappointed but how badly they will be disappointed. Program managers are the point people in delivering that bad news.

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Designer’s notebook
Microvias: An Answer to the High-Density Blues
Pros and cons – and costs.

It’s almost inevitable that a component that works well and lasts a long time will eventually be put on a list of parts not to be specified for mass production. Newer, better parts are on the way. The thinking goes that the microcontrollers and other devices on a board are already fine-pitch, so another one can be accommodated. That’s how we end up with those five-pin regulators with a tiny diamond-shaped pin trapped between four beveled rectangles.

Advantage: Component-to-component spacing. The via-in-pad trick enables high component density by enabling routing that is 100% internal to the board, with no exposed traces. The space normally set aside for the fan-out via can be used for the next component with the following stipulations:

  • Test access is maintained
  • Rework clearance (for desoldering)
  • Electrical isolation (shielding)
  • Thermal considerations (heat sink, heat pipe)
  • Mechanical interference (headroom)
  • Pick-and-place accuracy.
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The DIGITAL Route
Interaction: Cure for Industry Contraction
Back in the trade show swing.

It seems the electronics trade show industry had been shrinking the past year only to swell with a sudden, extreme realization venues are opening and plans that went dormant last year are coming back to life. August provided a swell of relief in the form of DesignCon. DesignCon was held Aug. 16-18 at the San Jose Convention Center, and PCEA was happy to participate with its first-ever trade show booth (FIGURE 1). A special nod from the PCEA executive staff to Eriko Yamato, our events coordinator, on design, coordination and delivery of our booth and some very special giveaway t-shirts for show attendees. Michael Creeden, PCEA vice chairman and treasurer/coordinator of our PCEA sponsors manned the booth throughout the show, with help from PCEA media coordinator Tara Dunn (FIGURE 2). Mike reports that while the show numbers seemed down a bit, the show had the spirit of a family reunion, and quite a few attendees were interested in hearing about the value of joining PCEA.

Jernberg pi
The Case of the Missing PDN Owner
With many disciplines contributing, who will manage the process?

As technology trends toward smaller, faster, cheaper, the challenges around good PDN design get more difficult. With multiple requirements needed from many disciplines, the PDN’s demands will only increase and become harder to maintain.

Over the past few months, we have discussed elements essential to power delivery and PDN requirements. Now that we have a better understanding of this, it’s time to explore what is needed to create the ideal PDN product, and who is best equipped to bring together all the elements of the PDN.

What is a good PDN design, and how do you achieve it? Power-related design objectives tend to be similar in nature for all PCBs: to provide sufficient current at a stable voltage to each device. What does vary widely is complexity, however. Said objectives can range from simple single-supply, powering a solid power plane, to a multi-source, hot-swappable, self-monitoring, thermally sensitive, complex design that accounts for most components and a large amount of copper on the PCB. Simply put, good PDN design delivers power adequately and reliably.

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material gains
Smart Manufacturing is Coming, but So Much More Could be Possible
We can make more (money) by making less (product).

Arthur C. Clarke once said, “Before you become too entranced with gorgeous gadgets and mesmerizing video displays, let me remind you that information is not knowledge, knowledge is not wisdom, and wisdom is not foresight. Each grows out of the other, and we need them all.”

Today, we’re all familiar with gorgeous gadgets, and not only those we carry in our pockets, wear on our wrists or help us drive our cars. The factories we work in are dripping with sensors and automation, which is increasingly robotized, bringing a level of dexterity, efficiency, and reprogrammable flexibility that previous generations could only dream of.

We are fortunate to live in this period we now call the fourth industrial revolution, although we should recognize our predecessors have been working toward this for generations. It’s simply human nature. Since the beginning of industrialization, people have been making analyses – of processes, end-products, and how things are done – to achieve some improvement. Often, the goal is to increase productivity and quality but also to ensure safety and reduce environmental impacts. Recently, of course, reducing pollution and energy consumption, while addressing issues like recyclability, has become increasingly important.

The Flexperts
What Kind of Solder Mask is Used on Flexible Circuits?
First differentiate between rigid-flex and true flex.
As is often the case with flex circuits, knowing which solder mask to use on flexible circuits is somewhat of a trick question, one with several answers. The decision boils down to circuit construction and design intent.

To start, there are several ways to insulate circuits in the flex world. These include solder mask, coverlay and coverfilm. In most cases, the designer may simply note solder mask per IPC-SM-840 and leave the rest to the fabricator. This allows the fabricator to use the proper mask in the proper setting.

When making a design decision, first differentiate between rigid-flex and true flex circuits.

Let’s cover the easiest one first: rigid-flex. Typically, a rigid-flex construction will have solder mask applied to the external rigid layers to insulate all external traces, as well as define surface mount or BGA pads. It may also provide mask dams between pads to reduce the potential of solder shorts at assembly. This solder mask usually is classified under IPC-SM-840 as a type H solder mask, which denotes a high-reliability solder mask. These are the most common solder masks. Normally green in color, they can be modified for other colors, as desired. It is worth noting that if the color deviates from the as-formulated green option, there may be feature resolution and web size tradeoffs. This is because the additives used to change the color impact how the mask material absorbs light energy during the imaging process. As a result, the fabricator may need to ask for some relief for other colors.

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Advanced Packages
008004s: Impractical, but Possible
Realizing advanced electronics with the world’s smallest packages. by Michael Schneider

Is it worthwhile to design printed circuit boards with the smallest component package available today: the 008004? And how do you do it correctly?

Several months ago, a hardware engineer in a high-tech company that is developing virtual reality headsets approached me. “These are special glasses that can integrate into game consoles in hundreds of millions of homes worldwide,” he said with excitement. “This is innovative technology that will enable a totally different viewing and gaming experience than what’s available at present.”

Later in the conversation, he noted they are developing a common electronic circuit board for a project that, after successful programming, has been proved by means of an evaluation board.

On the surface it seems promising. He then qualified their progress, however, adding that because this circuit board has a wide range of applications but a very small footprint, there is no room on the board to place all the needed components. After I received the technical details of the circuit board and parts list, I understood the possibility of building this assembly, provided we use the smallest component package. This is a component with dimensions of quarter of a millimeter by an eighth of a millimeter, known in the industry as an 008004.

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Solder Materials
The Interaction of 2 Solder Paste Alloys with 5 Surface Finishes, Part 2
SAC 305 shows faster shear strength degradation than Innolot,
while the surface finish has no effect. by Pritha Choudhury, Ph.D., Morgana Ribas, Ph.D., John Fudala and Mitch Holtzer
When a solder joint is exposed to cyclic stresses, thermally activated diffusion in the bulk solder, metallization and initial intermetallic (IMC) may take place. The growth of the interfacial IMC helps relieve the residual stress induced in the solder joint, and the growth rate corresponds to the magnitude of stress induced.1 Solder joint strength also decreases during exposure to temperature variations. Therefore, shear testing is a useful method to assess solder joint strength degradation caused by thermal cycling.2

In part one3 of this series we showed the voiding, solder spread and thickness of the high-reliability Innolot alloy compared with SAC 305 alloy solder pastes using five different surface finishes. Part two discusses thermal cycling effects on the growth in IMC thickness and solder joint strength. This study included two commonly used solder alloys in paste form:

  1. SAC 305 (96.5%Sn, 3%Ag, 0.5%Cu) powder size distribution (PSD) type 4 with novel “CVP-390” paste flux
  2. Innolot (91.95%Sn, 3.8%Ag, 0.7%Cu, 3.0%Bi, 1.4%Sb, 0.15%Ni) PSD type 4 with the novel paste flux and five variations of surface finishes, including
    1. Organic solderability preservative (OSP) (MacDermid Enthone Entek Plus HT) using two thickness levels
    2. Immersion tin (Ormecon CSN)
    3. Immersion silver (MacDermid Enthone Sterling)
    4. Electroless nickel/immersion gold (ENIG) (MacDermid Enthone Affinity).
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Industry 4.0
AOI Operation Control
by MES Using IPC-CFX
A connected factory automates the AOI validation process.
by Matthew Fischer, Ranko Vujosevic, Ph.D. and Loc Do
Automated optical inspection (AOI) is typically used after solder reflow to detect missing components and defects. Performing a successful inspection of a panel is not enough, however. Manufacturing execution systems (MES) are used for process control and AOI data collection to ensure the following are accomplished:

  • All prior routing operations passed.
  • Valid test program is loaded on the machine.
  • Test start- and end-times and test results are captured.
  • Failed printed circuit boards (PCB) cannot advance in the production routing and must enter rework loop.

One of the fundamental features of an MES system is routing enforcement. A machine can perform an operation only if the MES system verifies all prior operations have passed and the correct test program is loaded. All PCBs must be serialized to capture the highest level of traceability. The MES verifies that PCBs entering the AOI machine belong to the program loaded on the machine. Once the operation is approved, the AOI machine performs the test, and it sends board-in and board-out events and test results to the MES. The MES collects test results into a central database, which permits factory-level reporting, avoids having to locate results on individual machines, and protects against data loss. The MES also controls the routing flow and prevents a panel that fails AOI test from moving to the next operation. The panel must enter a rework loop, and defects must be fixed or the panel scrapped. In addition, the MES can analyze the test results and provide automatic feedback and program modification for pick-and-place machines to eliminate problems that occur in the component placement operation. This was not in the scope of this project.

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SMTAI
Inventing Your Own Path
The annual Women’s Leadership Program at SMTA International features two leading engineers.
by Priyanka Dobriyal, Ph.D.
SMTA International returns to an in-person format this year, with a virtual option, and the Women’s Leadership Program is in-person on Tuesday, Nov. 2! The past 18 months have been a time of reflection and transition for many of us. Many professionals are reassessing their career goals and career paths. In keeping with this trend, our 2021 WLP theme, “It’s good we are not all the same,” was chosen to encourage attendees to explore career transition options.

The WLP this year will focus on the success stories of women who have created varied career paths, applying core technical strengths to a variety of areas and succeeding consistently. Hear how their diverse career experiences have contributed to their long-term success. Our two distinguished speakers have blazed unique career paths and will share their stories with the audience.

SCREEN printing
Respect the Squeegee
Six areas to consider for optimal print quality and consistency.
IN THE STENCIL printing process, the squeegee blade often fails to get the recognition it deserves. Yet the squeegee is the item that does all the work and is the unsung hero. Consider a squeegee running in high volume on a 300mm board may put in between five and 10 miles per day of grueling aperture filling, and it becomes clear close attention to squeegee attributes may result in higher-quality results. With that said, here are my top squeegee awareness tips.

Material. In the early days of SMT, squeegee blades were predominately made from polyurethane (rubber), as the very first surface-mount printing processes used mesh screens. As the industry transitioned to metal-etched stencils and then laser-cut, stainless steel squeegees became standard. However, there are applications – such as heavily stepped stencils (say a 75µm step down on a 150µm-thick stencil) – where the compliance of a polyurethane squeegee is beneficial. The vast majority of squeegee blades today, though, are stainless steel. And not just any stainless steel; to be sure, a tremendous amount of IP and proprietary alloy formulation is in today’s sprung steel compounds used to manufacture high-quality blades. They keep a good sharp edge and provide excellent consistency for the pressure and force applied, which delivers the aperture filling necessary for a repeatable process.

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Defect of the Month
Microsections Can Show Much
Getting a close-up look at board quality.
A PRINTED BOARD microsection is one of the best ways to examine the quality of boards and any faults or failures.

The microsection (FIGURE 1) shows a plated through-hole that has been soldered with the nickel layer and through-hole copper visible. Normally, customers would accept the plating standards offered by the fabricator, or define their own, which may or may not impact the price. The nickel layer is part of the nickel/gold surface finish with the very thin gold of less than 1µm consumed during soldering and not visible. The remaining nickel is 5µm, and the copper is around 32µm. This is generous on many circuits board produced today and soldered very easily in production.

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Machines Materials Tools Systems Software
Easy-PC v.25 schematic and PCB layout tool
Number One Easy-PC v.25
Easy-PC v.25 schematic and PCB layout tool has more than 25 new features. Libraries can be altered and extended. Component search engine has over 15 million parts available for free download. Now enables differential pair definition, parameters, addition, editing, checking, and reporting.
Number One Systems
RGWxx65C hybrid IGBTs
Rohm RGWxx65C
RGWxx65C hybrid IGBTs have an integrated 650V SiC Schottky barrier diode in the IGBT feedback block as a freewheeling diode that has almost no recovery energy, thus minimal diode switching loss. Significantly reduce IGBT turn-on loss. Up to 67% lower loss over conventional IGBTs and 24% lower loss compared with Super Junction MOSFETs (SJ MOSFETs) when used in vehicle chargers. AEC-Q101 qualified.
Rohm Semiconductor
Thin film wraparound PHPA series resistors
Vishay PHPA Resistors
Thin film wraparound PHPA series resistors have power ratings of 1.0W and 2.5W in 1206 and 2512 case sizes, respectively, with a self-passivated tantalum nitride film for moisture resistance. AEC-Q200 qualified, with TCR down to ±25ppm/°C and tolerance to ±0.1%. For automotive power supplies, braking systems, on-board chargers, and motor deflection circuits, and industrial test and measurement equipment. Resistance range is 10Ω to 30.1kΩ, noise less than -30dB.
Vishay
Off The Shelf
off the shelf typography
Machines Materials Tools Systems Software
Intelli-Pro AI smart factory automation software
Mirtec Intelli-Pro AI
Intelli-Pro AI smart factory automation software and algorithm package consists of deep-learning-based automatic part search and teaching function; automatic parameter optimization; OCR; foreign object detection; placement inspection algorithms; and automatic defect type classification function. Cuts work time up to 90% over manual teaching and 50% vs. automatic teaching without deep learning.
Mirtec
3880-II die bonder
Palomar 3880-II
3880-II die bonder includes options to maximize productivity, reduce programming time by up to 95% and improve bonder productivity. Provides supports for rapid process development that minimize gaps in production caused by maintenance, calibrations, and process setups. New tool changer provides automated access to nearly unlimited tools. New contactless height measurement.
Palomar Technologies
NASA low outgassing rated epoxy
Master Bond EP5G-80
EP5G-80 is a one-component, NASA low outgassing rated epoxy with temp. cure requirement of 80°C for 4 hr. Graphite-filled compound is not premixed and frozen and has unlimited working life at room temp. Volume resistivity of 5-15 ohm-cm and thermal conductivity of 2.88-3.46 W/(m•K) at room temp. For heat-sensitive electronics with high levels of conductivity.
Master Bond
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Technical Abstracts
In Case You Missed It
Soldering
“Influence of Ultrasounds on Interfacial Microstructures of Cu-Sn Solder Joints”

Authors: Xu Han, et al.

Abstract: This study aims to investigate the interfacial microstructures of ultrasonic-assisted solder joints at different soldering times. Solder joints with different microstructures are obtained by ultrasonic-assisted soldering. To analyze the effect of ultrasounds on Cu6Sn5 growth during the solid-liquid reaction stage, the interconnection heights of solder joints are increased from 30 to 50µm. Scallop-like Cu6Sn5 nucleate and grow along the Cu6Sn5/Cu3Sn interface under the traditional soldering process. By comparison, the authors observed some Cu6Sn5 are formed at Cu6Sn5/Cu3Sn interface, and some Cu6Sn5 are randomly distributed in Sn when ultrasonic-assisted soldering process is used. The reason for the formation of non-interfacial Cu6Sn5 has to do with the shock waves and micro-jets produced by ultrasonic treatment, which leads to separation of some Cu6Sn5 from the interfacial Cu6Sn5 to form non-interfacial Cu6Sn5. The local high pressure generated by the ultrasounds promotes the heterogeneous nucleation and growth of Cu6Sn5. Also, some branch-like Cu3Sn formed at the Cu6Sn5/Cu3Sn interface render the interfacial Cu3Sn in ultrasonic-assisted solder joints present a different morphology from the wave-like or planar-like Cu3Sn in conventional soldering joints. Meanwhile, some non-interfacial Cu3Sn are present in non-interfacial Cu6Sn5 due to reaction of Cu atoms in liquid Sn with non-interfacial Cu6Sn5 to form non-interfacial Cu3Sn. Overall, full Cu3Sn solder joints are obtained at ultrasonic times of 60 sec. (Soldering and Surface Mount Technology, July 2021, www.emerald.com/insight/content/doi/10.1108/SSMT-06-2020-0026/full/html)

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