Tag Archives: printed circuit board

A New Trend in Assembly Shows?

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Years ago, three major events dotted the US electronics assembly trade show landscape. They included Nepcon East, Surface Mount International, and the mother of them all, Nepcon West.

While Nepcon West was the undisputed champ, all three shows were worth attending, and exhibitors often made new product announcements at each one.

Interestingly, and for reasons too detailed to get into here, none of those shows exist today. And for much of the 2000s, the place to roll out new products became IPC’s Apex. Other events were relegated to regional status, and traditionally were staffed as much by distributors as by OEMs.

There’s a few small signs that trend may be shifting again. While IPC Midwest, taking place this week in the Chicago suburbs remains a local show (and honestly, could they make seeing the exhibitor list any more user-unfriendly?), SMTAI is at long-last beginning to fill the niche for a seasonal alternative to Apex. To wit, we’ve received numerous press releases of late reporting new products to be introduced at SMTAI. That’s evidence suppliers see the venue as a viable place to make product launches.

Also at SMTAI, on Oct. 18, I am cochairing (with CIRCUITS ASSEMBLY columnist Sue Mucha) a panel titled “Global Strategies for Lowering EMS Costs” at SMTAI in Ft. Worth, TX. Topics include EMS in Eastern Europe; networking technical trends; improving quality, delivery and cost in high mix manufacturing; and vapor phase technology, and feature speakers from Kimball, Tailyn, Fabrinet and IBL Technologies. We conclude with a panel on building an EMS cost model.

I can’t mention these events without touting our own. Next week marks the 20th annual PCB West conference and exhibition at the Santa Clara (CA) Convention Center. Traditionally the industry’s leading conference for printed circuit board design and fabrication, we have beefed up the electronics assembly side (with a big assist from the Silicon Valley SMTA Chapter). Highlights include papers on low silver solder alloys, advanced packaging, new plasma-based PCB surface finishes, and lead-free electronics risk reduction, presented by such leading companies as Hewlett-Packard and Amkor. Check out the program at pcbwest.com.  We really hope to see you there.

Slippery When Wet: Plating High Performance RF/MW PCBs

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Once again, summer has evaporated at record speed. This morning, my two teen daughters trudged sleepily out the door for their first day back to high school; one a sophomore and one a senior. Wow…it seems like the first day of summer was just last week, and my kids were just starting kindergarten!

I suppose this sense of nostalgia is why I am now drawing a rather quirky connection between plating high performance multilayer circuit boards and Slip n’ Slides. I loved Slip ‘n Slides when I was a kid, didn’t you?! Injury almost immediately ensued just after you got the darn thing stretched out and flooded with water—but it was still a blast! It was equally fun watching my daughters slide, belly-down, along the long yellow plastic sheet when they were small. Afterwards, they stood up wide-eyed, dripping and giggling, and glued, head-to-toe, with tiny blades of grass. I also recall my utter humiliation when my kids and their friends looked on, with a mix of horror and pity, when I tried to throw-down some of my “old moves”, thinking I’d be the “cool” mom. (Sorry, girls!)

Memories aside, let me explain how I’ve come to connect Slip ‘n Slides and multilayer high performance boards. Plating is an aqueous (wet) process in which metallic particles are electro-deposited onto the surface of circuit boards. When plating high performance boards, which often employ Teflon laden materials, it gets a bit tricky. Because, well…it’s Teflon! It is very smooth and slick. (Think of Teflon coated cookware and eggs)

So, imagine that the Slip ‘n’ Slide plastic is Teflon substrate, and that your kid is a metal particle afloat in liquid. Now! Quickly and permanently bond the metal particulate (child) to the Teflon material (plastic), as it goes screaming by in a stream of moving water (aqueous bath). Yeah–well, welcome to our world! Plating on Teflon is not as easy as you might imagine. However, if we were plating on FR-4, or a ceramic-loaded substrate, it would be more like your kid attempting to Slip ‘n Slide on indoor-outdoor carpet. (Ouch!) The surface is rougher and more porous, even within an aqueous environment.

Don’t get me wrong, we love Teflon! It has many desirable properties, so we simply take steps to treat the material surface before plating to make it rougher and more receptive to metal deposits. There are effective and ineffective ways to accomplish this task, and only an expert understands the critical difference. So always choose those with expertise in fabricating these boards.

A second concern, in regard to plating high performance multilayer boards, has to do with ensuring a good solid ground connection. Some designers accomplish this by putting a front-to-back connective band of edge plating around the perimeter of the board. Others opt for dense hole patterns around the surface edges of the board. Not all board manufacturers are skilled at edge plating. It comes with a small host of potential problems. So, if you are opting for edge plating, you may want to ask for some edge plating samples and discuss the processes and concerns with a new potential supplier.

The third issue to be mindful of is the challenge of plating successfully when controlled depth, back-drilling, or selective plating are required. From this side of our manufacturing facility door, I often feel Dorothy-like in the presence of Almighty Oz in the face of these processes; I don’t fully understand what they do back there, but it all seems like magic to me! Many steps, and focused attention to multiple processes must be taken to be successful. Make sure any supplier you partner with is well versed in these technologies.

The final concern, as related to plating, applies to all boards—not just high performance PCBs. Features are forever shrinking, particularly holes that require plating. This can be problematic in that smaller holes are prone to trap air bubbles inside the hole barrels, which create voids where the plating is prevented being deposited on the hole walls. Four factors must be present and religiously controlled for even, consistent hole plating: filtering, agitation, aeration and circulation. Filtering prevents contaminants from affecting plating purity and integrity. Tanks and filters must be dutifully monitored. Agitation occurs when the panels are moved, mechanically, sided to side within the tank to help push out any trapped air bubbles and to ensure even plating inside the holes. Circulation and aeration pumps make sure the water moves briskly and continually circulates, also helping to push out tiny air bubbles and aid in even plating.

Here is the gist of what I hope you will take away from my ramblings this week. Plating is an uber critical process when manufacturing High Performance RF/MW Multilayer PCBs. So be sure you engage with skilled and seasoned experts who frequently and successfully produce these types of boards.

Otherwise, you may end up feeling like you’ve been helplessly tossed onto a Slip ‘n Slide….downhill…on asphalt. Yikes!!!

–Judy

Under Pressure: The Sticky Business of Laminating High Performance Multilayer Boards

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Bummer! Now, I’m going have Freddy Mercury camped in my head all day singing “Un-dah Presh-ah.”  Well, let me see if I can drown him out with discussing the Wonderful World of PCB Lamination. Even I want to run screaming from my own brain after contemplating this topic for very long!

Many times as I have thought about the various challenges of manufacturing High performance boards, my mind is helplessly drawn to make a comparison to bread making. When you think about it—they are both born from chemically based processes and formulas, right? Okay, maybe I need to cut down on the Food channel, but stick with me anyway!  For instance, there is grocery store bread that is mixed in towering vats, and baked in loaves by thousands, and then there is Artisan bread. Mmm…that warm, wonderful, crusty bread, that is made in small batches by passionate bread makers.You know the ones; they waft with the tangy fragrance of things like fresh rosemary or garlic. These breads often boast of secret recipes.  Some areas of Italy have famous breads, whose bakers claim that it is the water, unique to that region that makes it special.

Regardless, both types of bread have value and a place in our lives.

In my visually, and apparently culinary driven mind it goes like this:

FR-4 boards = Wonder Bread 
RF/MW/High performance boards = Artisan Bread

With this in mind, let’s consider multilayer designs that include high performance materials—either on all layers or on selective layers.  What is required for successful production of these boards?  Once again, we need material gurus who are fluent in the knowledge of high performance materials and how they behave.  In this case, specifically, how they respond to lamination; because, as I’ve said many times, they all act uniquely.  Each high performance material comes with its own lamination profile, a recipe of sorts, which specifies the temperature rise rate, as well as the cooling rate.  These are provided to us by the material manufacturers, however, this recipe must be “tweaked” for the Press being used, and the environment in which it is being produced.  In other words—we are back to that intangible, though critical aspect of Art and Magic—like Artisan bread making!

A second concern, during lamination is the surface treatment of the layers.   All boards must be cleaned thoroughly and put through a scrubber prior to lamination.  This ensures that the surface is free of all contaminants and debris that would prevent strong, even adhesion or create de-lamination in the future.  High performance boards require special TLC at this stage of fabrication.  They cannot be treated like standard boards due to the material composition.  A little known secret, at this stage of fab,  makes all the difference—but if I told you what it was, I would have to kill you.  (Sorry, it’s part of our secret recipe!)

When standard multilayer boards are made they are “booked” by stacking the layers together with pre-preg placed between each layer to act as a bonding medium (epoxy-resin loaded fiberglass sheets).  When you have varying substrates on various layers, that formula goes out the window.  Farewell, Wonder bread.   Every high performing material has a corresponding bond ply that matches its properties in order to bond properly and also for performance reasons.  This information is supplied by the material manufacturers as well. It is critical that a RF/MW/High performance board manufacturer be current and well-versed on bond plies. Hello Artisan bread.

The last item of interest, when it comes to lamination, is the impact of the environment on High Performance materials. All substrates are somewhat impacted by humidity, this is especially true in some types of High Performance substrates.  They are very vulnerable to humidity and the environment. Awareness of which materials are most vulnerable and how to treat them are crucial to success.

It all comes down to this:  Only Master Bakers make Artisan Bread! Artisan bread makers are able bake Wonder bread, but beware of the baker who makes Wonder bread everyday and tells you he can make you a great loaf of Artisan bread!

Master Board makers successfully and consistently make RF/MW and High Performance boards because they have the knowledge, skill, experience and all the secret recipes that make for a top-notch high performance product. Therefore look for the qualities of a “Master” when you evaluate potential suppliers.  It will save you much time, frustration and headache if you do.

Bon appétit!

–Judy Warner

Is Flat the Next Big Thing?

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The Human Media Lab at Queen’s University, Canada and Arizona State University’s Motivational Environments Research group have teamed up to create what’s been dubbed the “PaperPhone.”  The phone was created with the same e-ink technology found in the Kindle e-book reader and in flexible printed circuits featuring an array of bend sensors.

E-history: the world is flat, but bendy. The first electronic paper, developed in the 1970s in Palo Alto, was called Gyricon and consisted of polyethylene spheres between 75 and 106 micrometers across. In the 1990s another type of electronic paper was invented by Joseph Jacobson, who later co-founded the E Ink Corporation.

In an electrophoretic display, particles with a diameter of one micrometer are dispersed in a hydrocarbon oil with a dark-colored dye with surfactants and charging agents. This mixture is placed between two parallel, conductive plates. With applied voltage, the particles will migrate electrophoretically to the plate bearing its opposite charge.  Arranging this movement into patterns — in this case pixels — is the basis for a paper thin display.

Although called the “PaperPhone”, the name doesn’t quite do the prototype justice. “SmartPaperPhone” may be more fitting. The device can perform several tasks, depending on what shape you form it into.  Want to make a phone call? Bend the paper into a concave shape. Have a favorite e-book? Bend the page corner to turn to the next page. You’ll even have an mp3 player that’s much thinner than your current iPod.

E-regulatory compliance. As far as regulating something like this is concerned “the electronic components and lithium batteries are not regulated as hazardous waste. The entire electronics assembly is RoHS (Restriction of Hazardous Substances) compliant and marked as such on the printed circuit board in the cover. All of it can be recycled through your local municipal waste program in the same manner as you dispose of household batteries. (Check local regulations for any further restrictions.) The paper can go in your paper recycling, and the protective foam in your plastic recycling.”

E-exciting or e-issues? While exciting, there are some issues with the PaperPhone. Batteries are still fairly clunky and won’t easily bend. The memory has to be kept somewhere as well. What good is a flexible electronic paper phone if most of is has to stay stationary to accommodate the required working innards?

It could be that buying a ream of cellphones at your local big-box retailer may not be that far off.

Learn more about the technology below:

http://www.hml.queensu.ca/paperphone
http://www.circuitsassembly.com/cms/magazine/209/9557/
http://www.esquire.com/features/how-e-ink-was-made
http://supply-chain-data-mgmt.blogspot.com/2011/05/green-chemistry-sleeper-hit-in-supply.html

Adam Baer (guest-blogger for Kal Kawar) manages materials regulation data and reports at Actio Corp.  He holds a B.A. in Journalism from the University of Maine.

A Big ‘Yeah!’ for Yacoub

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Congratulations to Advanced Circuits CEO John Yacoub, who has been named a finalist for the Denver Business Journal’s Entrepreneur of the Year.

From an inauspicious start — in his first week on the job, they told him the plant would be closed because of environmental reasons — John helped turn the company into one of the prime examples of American ingenuity and character.

The recognition is good for John and Advanced Circuits, of course, but it’s also vital for the printed circuit board industry to get this kind of positive press. Way to go!