Author Archives: Judy

The Value of Doing It Right … the First Time

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Recently, I had the pleasure of meeting with a gentleman that, though now retired, spent a long and illustrious career in marketing and advertising. Some of his best known clients were Wendy’s restaurant, Budweiser and Coca-Cola. Since part of my job is marketing (in which I have no formal training) I took advantage of this opportunity to learn all I could. As he was going through some fundamentals with me, I was having trouble applying the theory to our printed circuit board business.

We discussed why people would buy from Transline over a competitor. I spit out the expected answers of price, service, expertise, etc.  I could tell, from his expression, that I was not only missing the bulls- eye, but the entire target. How embarrassing! He then asked me what kind of problems we solve for our customers. With animation and passion, I explained what I have said many times here on this blog: People keep inadvertently using board houses that don’t specialize in RF/MW and it costs them a tremendous amount of time, money and grief. He smiled, and I knew I had stumbled onto something. He said, “That is what you do for customers…you make it right The First Time!”

Do it right the first timeIt was so stupidly simple, how had I missed it all this time?!  It is alarming to think about the waste of time, energy, money, resources, and stress that can all be avoided by doing one simple thing:  getting it right the first time!

I saw this illustrated recently when my husband’s 2004, used, BMW had an irritating problem. It has one of those electronic keys that you insert into a slot and simply push a button to start the car. Randomly, the car began to not start up—but only intermittently. It was frustrating to get in the car and not know if it was going to start or not. One day, the entire car shut down while my husband was driving it, which crippled all the electronic systems. Luckily, he was in a parking structure. He took the car to his mechanic/friend’s shop.  I felt this was a mistake because this shop doesn’t often work on high-end imports. I suggested to my husband that we just pay the big bucks and go to a BMW dealer who would thoroughly understand the electrical system and fix it quickly.

As I feared, the car sat for over two weeks at his buddy’s shop while the electrical guy tinkered and tried to resolve the problem. Meanwhile we played musical cars at our house that now has 2 teen drivers and 4 wildly conflicting schedules. What a hassle! We were getting ready to take it to our local BMW dealer, and take the financial hit, that we knew was going to be ugly. Instead, I did some searching online for an independent BMW repair shop in our area. I was ecstatic when I came across a small shop whose owner was trained by BMW, in Germany, on electrical systems! My husband took the car over the same day. The owner asked him where his second key was. My husband explained that he bought the vehicle used and that it only came with one key. The owner said he wouldn’t touch the car until we bought a new key, explaining that there was a good chance that the key was the problem and that buying a new key would be far less costly than doing a full electrical analysis on the car. Sure enough, when we got the key a few short days later, the car ran like a charm—saving us time and a boatload of money.

The lesson for me here is, that if we would have just gone to the specialist in the first place, we would have saved time, money and lots of inconvenience—because he was an expert and he did it right the first time!

Since my meeting with the marketing-guru, I’ve gained a fresh appreciation for the enormous value Transline brings to the RF and Microwave market by being experts, and doing things right the first time. We are like that German-trained mechanic. We bring insight, expertise, time savings, resource savings, and stress saving services every day, by knowing our products and doing things right the first time—but not charging exorbitant prices to do it!

This was an insightful lesson that I wanted to pass along. Not just to promote Transline, but to invite you to think more deeply, yet simply, about what value you bring to the table—as an individual or company. The clearer and simpler we can make our message, the easier it will be for others to grasp what value we have in respect to resolving their problems. Face it; simplicity and clarity in our complex industry, and world, are desperately needed!

I would love to hear your feedback on this subject. Please comment here, connect with me on LinkedIn, or email me at [email protected].

Best wishes! Judy

Living La Via Loca

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I got an email a few weeks back from one of our customers who is with a semiconductor manufacturer for whom we make evaluation boards.  He asked some good questions that I answered, of course, and I thought this information may be useful to others, too.  Here is what his email said:

Hi Judy, We received the boards today… and they look gorgeous!  And of course it leads to a question….. not a negative, not an “inquiry” style question….

One thing that caught my eye was how “flush” the board surfaces were.  I wasn’t able to identify a single via on the front or back surfaces of the board…. and (education time) I had an Apps Engr point out that I could see the via plugs by looking at the edge of the EVB.  So I want to understand more about the via fill process, and whether there are different options that influence cost and lead time.

I will share with you my brief answers, which are not overly technical. However, I will follow my comments with a link to a very good in-depth paper from Michael Carano of the Electronics Division of the OM Group on this subject. Unfortunately once you start talking about via filling and plugging it is a bit like opening a big can of worms!

First of all, a semantics lesson:  There are two methods of filling via holes—one is via “filling” and the other is via “plugging.” Via hole filling refers to the non-planer filling of plated through-holes. Via hole plugging refers to the planarization of blind and buried vias, as well as through holes. Via hole plugging pertains to HDI and microvia designs.

(In the case of the above customer they requested the through-hole vias to be plugged with conductive  ink that would facilitate a connection from the front to back sides).

Once the conductive ink has been applied to the holes, the conductive ink must be cured. After curing some of the cured material will protrude from the holes leaving a small bump or “nail-head.” At this point the board must be “brushed” to flatten this protruding bump, with micro precision, to remove the excess material without removing any material from within the via hole. The brushing process must not damage the knee of any unplugged holes. This requires the use of a very flat working surface and special brushes. In some cases there may need to be an additional final cure for hardness. (UV)

Getting back to our customer, we took all these steps to properly fill, cure and planarize the plugged vias. Afterwards, these boards went through final outer layer pattern plating, which further erased any evidence that the plugged vias were present.  This made it impossible for our customer to detect any sign of the plugged vias (unless they peered through the side of the board into the substrate where they could see the front to back plugs). I think they were a little worried we forget to plug them at first glance!

As far as how filling verses plugging vias influences cost and lead time—the HDI via filling does take some extra time and TLC and thus raises the cost, and may or may not affect the lead time. Usually you must allow for one full day to complete the via plugging process.  Obviously if you need a quick turn, the lead time would be affected. However, if the lead time was standard, it probably wouldn’t make much of a difference. It stands to reason that the quantity also comes into play in regards to time and cost.

Thank you, Bill for asking these questions—they were good ones! We appreciate your kind words and commitment to our partnership. We are thrilled you think our boards are “gorgeous!”

I would also like to thank Michael Carano for his expertise and outstanding paper on the subject of filling and plugging vias that can be found here: http://www.electrochemicals.com/viafill07.pdf

Keepin’ it Smooth: How Surface Roughness Impacts High Performance PCBs

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First a disclaimer: I am not an electrical engineer. I am only fluent in my knowledge of PCB fabrication. In other words, much of what I am about to share is borrowed from well- educated and experienced EEs who don’t share my aversion to math. I am, in effect, jumping into the deep end of the pool, but only because I am wearing my (virtual) brain floaties! For this reason, I ask for your forbearance as I attempt to translate this left-brained subject matter into my right-brained mother tongue. Here we go…

Substrate copper application methods. I have been discussing surface finishes for the last couple of posts, and I would be remiss if I didn’t cover the crucial topic of copper surface roughness and how it specifically impacts high performance PCBs. Most substrates are copper clad with either rolled annealed (RA) copper, electrodeposited copper (ED) or reverse treated copper (RT). I have put some links below should you want to learn more about each type of copper and the resulting surface roughness of each.

When the copper surface is rough, even at microscopic levels, the effective conductor length grows and the resistance increased as the signal must move up and down with the topography of the copper surface. To the naked eye, copper-clad substrate appears very smooth but when you view the surface under magnification, the copper can look like something akin to the Himalayas! For this reason, some choose RA copper that is both smooth and consistent in thickness. RA can be more costly, however, and not an option for all. ED copper has the roughest surface but, depending on the application and speed requirements, may be perfectly adequate. RT copper is smoother, and doesn’t cost more than ED. Yet with RT copper you need to be careful about potential delamination and poor peel strength. Once again, we are back to trade offs and specific design needs!

Rogers has a “LoPro” laminate series that is extremely smooth while Taconic offers an extremely smooth “reverse treated/ED” clad laminate. These laminates aid in good, sharp etch definition as well. In some cases, these are smoother than RA copper and can be less costly.

Skin Effect Considerations

  • Michael Ingham of Spectrum Integrity shared the following illustrations with me in regards to the skin effect and how a signal flows through a conductor. In the first illustration, he shows a rough cross-section of how a very high frequency signal tends to run on the outermost areas of a conductor—creating the skin effect. However, he notes that this is only true when there is not a ground plane underneath.
  • In the second and third simulation illustrations he used a full 3D field solver for a top layer trace that has a ground plane beneath.
  • The second illustration shows how a current will flow through the entire trace cross section area at low frequency.
  • Finally, in the last illustration, he shows the current distribution at 20GHz, which is mostly at the bottom and sides of the trace.

Fig 1 Current Flow

Michael’s point is that when it comes to surface finishes and texture, the most critical issue appears to be the smoothness of the copper. He has raised the question that if the high-frequency current mainly flows on the bottom and sides of a trace—is using nickel really causing the unwanted losses, or is copper roughness the culprit? Many fear using ENIG-plated traces and go to great measures to avoid and resort to using costly mixed plating, etc. Below is measured data of a RF trace with standard ENIG plating. The overall loss may be surprising.

Fig 2 Insertion Loss

This is just scratching the surface (no pun intended!) in regards to the topic of conductor losses and copper profile. When dealing with coupled trace structures, the effects of nickel could have a big impact due to having adjacent trace walls interacting. But I will leave this topic for Michael to cover at another time!

Spectrum Integrity has been very successful in high-speed/high performance designs, and has done so focusing more on design technique and paying great attention to all the properties of materials such as the smoothness of the copper rather than focusing on surface finishes or restricting to very low dielectric loss materials. They have enjoyed very good success with avoiding costly mixed plating and with the use of smooth copper laminates like the Taconic RT/ED material.

When it comes to the smoothness of outer layer copper traces, a board fabricator can go a long way to hurt or help your desired results! The higher the speed/frequency and more critical the application, the more you need to be working with a company like Transline Technology who understands high performance board fabrication. For instance, when we clean the outer surface of the boards, we do it with chemical cleaners that are non-abrasive and maintain the smooth copper outer surface. Additionally, there are many points throughout the manufacturing process where standard practices of PCB handling can also compromise the otherwise smooth copper outer surface that can create havoc for your design performance. High performance boards can appear deceptively simple in their design, but there are many intricate details that must be considered when making a sound high performance board. Many a board fabricator does not possess the knowledge or the trained eye for the subtleties of high performance PCB fabrication.

Conclusion. Skilled and well-informed partners are the key to success when it comes to choosing surface finishes and materials for high performance designs. These issues are complex and have many nuances that must be considered to create successful products. As such, it is critical to forge strong working relationships with both your advanced material suppliers and your board suppliers. By doing so, you will save much time and money and avoid a host of needless headaches. I have listed some additional resources below. Many thanks to Michael Ingham of Spectrum Integrity, who is always teaching me something! I highly recommend Spectrum Integrity for RF/MW and high performance design. Their website link can be found below. As always, I welcome your input and comments! [email protected]

I also invite you for lively discussion regarding High Performance board design and fab on Linked In: http://tinyurl.com/85ymddk

–Judy

 

Additional Resources

http://tinyurl.com/7he2lmv

http://tinyurl.com/7wnewcq

http://www.polarinstruments.com/support/si/AP8155.html

http://tinyurl.com/7yblg4m

http://www.spectrumintegrity.com/

http://www.rogerscorp.com/documents/1183/acm/RO4000-LoPro-Laminates.aspx

http://www.taconic-add.com/en–products–material-view.php

Getting the Right Finish, Before You Start

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If you are a fan of John Wooden, the celebrated UCLA coach, you will know that he had more than his share of clever sayings. My husband, who played basketball all his life, and who went to college on a full-ride scholarship—nearly worships Coach Wooden. For this reason, I have heard many of these wise and witty Wooden-isms over the years. One that comes to mind is: “Be quick, but don’t hurry.” With the speed of advancing technologies, we all have to be quick, but we cannot afford to hurry—or be hasty—putting revenue and market share opportunities at stake.

In regards to RF and microwave printed circuit boards, there seems to be some confusion about PCB finishes and their affect on the high performance requirements of these applications. Too often, when considering the available finishes and the potential impact they have on performance, many engineers become both quick and (unwittingly) hasty when they make finish choices based on information, which is conflicted, at best.

I think it’s time to clear up some of these issues, so I am going to spend the next few blog posts talking about these issues. Hopefully, by the time I’m through you will have a much clearer understanding of finishes and which to choose for your product, before you start! I will be drawing from our real-world experiences, as well as looking to experts in the substrate and RF design industries.

Today, I am just going to cover the major available finishes, and which ones seem to be preferred by those with high speed applications:

  • Tin (Lead free)
  • HASL (Hot Air Solder Leveling) Tin/Lead 63/37
  • ENIG (Electroless Nickel Immersion Gold)
  • ENEPIG (Electroless Nickel/Electroless Palladium/Immersion Gold)
  • Hard Gold
  • Soft Gold
  • Immersion Tin
  • Immersion Silver

In high-speed applications, the prevailing wisdom suggests ENIG, ENEPIG, hard gold, soft gold and immersion silver are the best choices. Gold is a natural choice due to the fact that it does not oxidize and that it is wire-bondable. Immersion silver is gaining some traction due to the excellent conductivity, but it oxidizes and it is not wire-bondable, which keeps many from choosing this option.

Unfortunately, I must leave us barely posed in the starting blocks, in regards to finishes! In two weeks, however, I will sound the starting shot, and we will be off to the races. I will discuss each finish in more detail with the pros and cons of each.

If you have specific questions you would like to submit about this subject, please post them here in the comment section or email me at: [email protected].

I’m looking forward to tackling this complex and critical subject together!

 

–Judy

All’s Well at West

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We really had an outstanding week at PCB West. Preshow registration rose to nearly 2,000 (!) and actual attendance was up more than 30% over last year.

Congratulations to Judy Warner and Michael Ingham, whose talk on RF/microwave design and fabrication drew more than 100 attendees, the most in the conference. Newcomer Jamin Taylor’s presentation on flex construction also drew more than 80 folks. Well done!

I also want to congratulate the winners of the PCD&F NPI Award for best new software tools of 2011. They include:

  • Design Verification Tools: DfR Solutions (Sherlock Automated Design Analysis)
  • Computer-aided Design (CAM) Tools: Downstream Technologies (CAM350)
  • Documentation Tools: Polar Instruments (Professional HDI Stackup Design & Documentation)
  • PCB Design Tools: Altium (Altium Designer 10)
  • System Modeling and Simulation Tools: Sigrity (SystemSI – Parallel Bus Analysis)

We have posted the full announcements on PCD&F’s site. Thanks to all who attended!

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

Getting ‘Mixed Signals’ from Your PCB supplier?

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A few weeks back, I was having a chat with a national PCB broker who has a unique and broad perspective of the printed circuit board and electronics industry. We were waxing nostalgic about the “old days” and philosophizing about the days to come.

When she asked about our company, Transline Technology, I told her that we manufacture a wide variety of boards, but that our strength and focus lay in RF and microwave products, which account for about 60% of our business. I was bragging about our work and our customer base when she abruptly interrupted, “You know, Judy, not all board suppliers who say they can make RF boards really can.”

I was caught off guard and asked her to elaborate. She recounted several horror stories whereby she had placed RF/MW PCB orders for her customers and the suppliers failed, in one form or another, leaving her embarrassed and in search of a more qualified supplier.

This puzzled me. Although I have been in this industry for over 17 years, only this past year has involved RF/MW PCBs. Transline is a relatively small shop, and we are very successful with RF, so I assumed most others were as well. I wondered why, in some cases, much larger, far more well-recognized suppliers were failing? I tucked this question away for later consideration.

A week or so later, I was talking to the owner of a RF/MW design firm, a new prospect, who tends to take on very complex RF boards. It was like déjà vu. I was bragging … then interrupted … and the tales of woe poured out like an overdue confession on Sunday morning. This time I dug deeper. By the end of the conversation I had a new friend and customer.

Same week … different RF engineer … same story. Déjà vu, squared.

By the end, of these exchanges I was left with this conclusion: Not all PCB suppliers that say they can build RF/MW PCBs can!

So what makes RF/MW boards uniquely challenging to build? Why do some otherwise excellent board suppliers, have trouble with RF/MW PCBs?

I sat down with the owners of Transline, Larry Padmani and Chris Savalia, and asked them to share some of the inherent challenges in manufacturing RF/MW PCBs. They looked at me with cocked heads and compassionate smiles, as if a wee toddler just stumbled into their offices and asked them where babies come from. Clearly, these were loaded questions.

Their patient answers came and I soon experienced the proverbial sensation of “drinking from a fire hose.” It soon became clear that the answers were many and complex. I soon understood that there existed a chasm between most RF/MW engineers and their board suppliers that sorely need to be filled. It was then, I decided, I wanted to somehow help fill this gap … for a couple of reasons. Altruistically, I wanted to spare RF/MW engineers from needless suffering, before they found a well qualified PCB supplier. More selfishly, I knew if I could adequately inform the RF/MW community, they could more easily discern between a qualified and non-qualified supplier — and I knew it would become clear which camp we fall into.

So, I decided I would write an article for one of the trade magazines.(I may not be able to do complex RF calculations … but I can write!) I began by putting out questions to the RF/Microwave professionals via LinkedIn, asking what they would specifically like to know about RF/MW PCB manufacturing. There came a small flood of questions that continue to flow. I felt suddenly naïve and ill-equipped for the job!

Then two small miracles happened. I met a colleague who spent most of his career working for Rogers and Taconic on a nationwide scale. He offered his help in educating me on material properties and helping understand both the engineering issues and manufacturing challenges. His help, along with patient tutelage of owners of Transline, promise to bring me up to speed.

The second miracle was meeting Pat Hindle from Microwave Journal, who was commenting amidst the mix of my brewing discussions on LinkedIn. He pointed me to helpful resources and, he astutely observed, that this topic may be too broad for one article. In the weeks ahead I will take on the challenge of addressing the broad range of questions and issues surrounding RF/MW PCBs one-by-one. I know I will learn much, and hope to teach a little and help bridge the gap between RF/MW engineers and board manufacturers.

Keep the questions coming, both here and on the LinkedIn RF and Microwave community. I will do my best to address each one!

— Judy

http://www.translinetech.com/

Ed.: Judy Warner is director of sales and marketing for Transline Technology, Inc., in Anaheim, CA. She has been in the printed circuit board industry for nearly two decades. Her career began with Details, Inc. (later to become DDi). She was a top-producing sales professional for 10 years for Electroetch Circuits (later to become Tyco, then TTM). She also spent several years as an independent sales representative, including time as the owner of her own rep firm, Outsource Solutions.