Deep Into Technology at Compunetics
There aren’t many printed circuit companies in my neck of the woods. There is one, however, that has always fascinated me, and that is Compunetics, in Monroeville, Pennsylvania, a suburb of Pittsburgh. Having worked with them on the electrophoretic photoresist, a PPG product, many years ago, it was great to stop by and catch up with CTO Tim Schmitt and Technical Applications Manager Jesse Ward, along with General Manager Burhan Capar, a relative newbie to the company. As always, they are deep into some very interesting technology and always pushing the boundaries of what is possible in that realm.
Patty Goldman: Hello gentlemen. It is great to be here to talk technology and learn what you guys are up to here at Compunetics. How about we start with a little background about yourselves and your roles here.
Burhan Capar: I joined the company as the division manager about eight months ago. I had spent the previous 25 years in the printed circuit board industry with one company, prior to coming here. My charter is to grow this business, which operated as a semi-captive shop for many years. My career in the industry has included running sales, marketing, operations, and I was the president of my former company. This is a great opportunity for me. I am thrilled to be running a company that has this level technology and capabilities. What I am most thrilled with is the opportunity to be working with the most educated and talented group of engineers and scientists in the industry. We know that there is a real need in the PCB industry for a high-end shop with superb engineering and technology.
Jesse Ward: I’ve worked with Compunetics for 10 years and I am the technical applications manager. My background includes project engineering, front-end engineering, sales engineering, and technology development; most recently, I’ve been training in marketing and business development. For the past 10 years, I’ve managed highly technical projects from cradle to grave, including various flex, rigid-flex, HDI, custom requirements, and other aspects of advanced printed circuit boards.
Tim Schmitt: I've been with Compunetics over 30 years. Currently, Compunetics is one division of the larger organization, which is Chorus Call Inc., an ESOP company. The 650 employees of all the divisions have always been and continue to be the largest stockholder of the company. Compunetics has been producing printed circuit boards at this facility continually for the past 47 years. Dr. Giorgio Coraluppi founded the company in 1968 and continues to lead it today.
Dr. Coraluppi leads this organization with one goal for all divisions: maintaining a focus on leading edge technology. With that in mind, we've developed a broad range of technical capabilities. We service pretty much most markets—medical, satellite, military, etc.
Goldman: I’ve known Compunetics for a lot of years, and I’ve been in this shop quite a bit, so I know you do some pretty nifty things, especially with your electrophoretic photoresist, which I worked with. Maybe you can talk about that?
Capar: Our company has an incredible amount of technology, including the electrophoretic photoresist process, which really is an enabling technology. Since my arrival here, we have found new uses for that technology, including a bussing scheme for recessed gold fingers. That is just one of the technologies that we have here. We are one of the few small- to medium-sized printed circuit board fabricators to have a fully automated horizontal electroless plating line. We also have a semi-automated reverse pulse plating line and semi-automated DC plating line. We have a 16-watt laser direct imaging system and a brand new Hakuto cut sheet laminator. The company has the technology and it has the capabilities that most very large companies have. I can confidently say Compunetics has higher technology than any other company of its size.
Every day we run 3-mil lines and spaces. We can do 2-mil lines and spaces using our electrophoretic photoresist. We have a team that is working on 1-mil line and space technology now. Our parent company’s PCBs are generally 18-layer boards so high layer count is common for us. High aspect ratio work is a specialty with a horizontal electroless line and automated reverse pulse plating line. We are very good with flex and rigid-flex, including flex circuits with constantan instead of copper. We also play in the IC package substrate market. We have superb capabilities in the RF/microwave and high-speed digital/SI markets.
Goldman: Some of that is the neat stuff that Tim and I wrote about some years ago. You’ve been doing some interesting technology for many years.
Schmitt: We have developed many technologies and they're on our technical shelf. We have an engineering team that is capable of using these technologies and are constantly developing new technologies. That's the name of the game here, developing new market-driven technologies. We've had very high end customers that required new technologies and required them in a certain time frame, an aggressive time frame. They actually paid our engineers at a cost-plus rate to develop their technologies at our site. Those are the kind of relationships we have with our customers—long-term because we have the engineering expertise they need.
Goldman: Basically, they're partners with you.
Schmitt: They're partners, yes. Partners for the technology that they need now and might need in the future. Based on that, we'll go over some of the technologies from long, long ago, up until today. As you've heard, we have electrophoretic photoresist here. We've had that for at least 15 years. At the time, we installed this we were doing 2-mil lines and spaces with it. Test vehicles were sent out to test centers to determine our yields, etc., and it worked out pretty well. That is a technology that we still have. We were doing 2-mil lines and spaces when nobody really wanted them, because there was no such thing as a microvia, so it was developed before its time.
Goldman: But you had customers requesting it?
Schmitt: We had a few customers requesting it at that time. One was a medical customer and this was many years ago. It was an X-ray multi-chip module that had a 35-micron space and trace, that's a 3-mil pitch, and it allowed that X-ray detector to do very high-resolution real-time X-rays. That also included wire-bondable gold ball bonding, etc. That was one of the first big projects we had. One of the second projects we had was for a large government agency, and it was for chip carriers that at the time had 2-mil lines and spaces, and they had microvias. We also installed a nickel heat sink on the board. We made many thousands of these for that customer.
In addition to that, in our early fine line days we did a lot of chip packages with cavities. They had multiple shelves on them. They were all 2-mil lines and spaces, all wire-bondable gold. Another technology that we used at the time was buried resistors. For a supercomputer company on the West Coast, we did BGA cavity boards with buried resistors, and in some cases they were laser-trimmed buried resistors. We also have the capability of doing buried capacitance, which is in use at one of our other divisions.
Some of the other technologies we have are for satellite flight-certified boards. These multilayer flex boards use non-copper conducters. This material is made at our facility. We also have the capability of making heater boards on flex using Inconel conductors and coated with PTFE. This is a standard heater board that is used in the medical industry and in some DOD applications. Also, a NASA X-ray detector on multilayer LCP with 2-mil line/space and ball wire bonding. This was the Rogers product of the year at the International Microwave Symposium seven or eight years ago.
It has been an exciting journey but what’s more important than all this history is the future…what are we working on now and what do we have our eyes set on?
You mentioned padless vias. With the electrophoretic photoresist there is padless via capability. We have interest from a couple of large radar antenna companies and some packaging companies that are interested in padless vias. That's a new technology that we've had, but no one's been interested in it until now, so that may be a technology that will be pertinent and we'll be focusing on in the near future.
Lately we've been doing a lot of work with a new technology called Ormet, which is a process that allows you to bond together sections of printed circuit boards using sintered copper, much like they used to do back in the days of the ‘60s and ‘70s with the first large computers. They're doing that again for antennas, chip testing interposers, etc., with Ormet technology.
We've had our laser drills here for quite a while doing microvias. We do stacked microvias, and we have special chemistry for them in our special reverse pulse plating line. With that and the fine lines, we're able to do flip chip packaging right now down to 200-micron pitch, so we've done quite a few of those for some West Coast customers. Of course, we do lots of flex and rigid-flex. Now we do a few technologies that I'm going to let Jesse talk about, that he's developed for a defense customer. One technology, and there's a lot of interest in this, is used for some of the superconducting chip carriers, interposers, etc., and for quantum computing. I'll let Jesse talk about some of the bumping technologies and three-dimensional boards.
Jesse Ward: The bump and bonding technology involves copper-plated pillars. They can be down to about 6 mils in diameter, possibly smaller and of variable height, but typically around 2−3 mils in height. What this allows is for an extremely dense mating footprint for essentially testing chips at high speed, usually cryogenic application superconducting. I guess you could think of it as a flip chip alternative. It's occupying a space like a flip chip would but it's not using solder. It's simply pressure contact, so it's reusable. They're getting a lot of uses out of one board, so they can test different chips, the same model, over and over and get a lot of data out of one board before having to discard it and use a new one. The customer really likes the economy they're getting from this.
We've expanded that to an even more economical solution. At the bump bonding site, you're pressure contacting those bumps so they're reusable, but on the other end of the board you have soldered pins. They've eliminated the soldering of the pins using a castellation. So our customer is using a spring-loaded socket to attach the socket to the PCB. Again, this is non-solderable and it's reusable, so you can kind of think of this board as a 3D board where on the edges of the board are the castellation sites for the spring-loaded socket connector. This can be of any dimension in X and Y. Then it can transpose or connect to blind vias that fan in or out to the chip.
You can essentially think of it as a 3D structure that can have custom dimensions for the chip and custom dimensions for the socket, while having extra areas for mounting the piece. I guess this 3D design was somewhat of a collaboration between Compunetics and another customer, but it was our intellectual property or idea that led to the actual form of the non-standard castellation. It's not a plated through-hole wall—it's different, but we're probably not ready to say what that is yet. The bump bonding is very popular. There are several customers that like it and it seems like it's on the rise.
Goldman: Always something new to work on; there’s never a boring day.
Ward: Exactly. This castellation design has been extended to be sort of multi-purpose. On one end of this board it doesn't have to be a bump bonding attachment. It can facilitate any type of mating. We've expanded this castellation design to include multiple features, different features, so it's sort of a multi-purpose economic solution.
Goldman: Another example of partnering with your customers to develop a new technology and new methods.
Ward: Right. It took a couple hours in a conference room of going back and forth with ideas, and it's not something you're going to do on the phone. We had to sit down and hash out all the details. It was a collaboration. Doing it was not as much fun, but we got smart about it along the way and learned how to save some steps and cut costs, and make it more affordable for us and the customer.
Goldman: Then you made it work, and that was fun.
Ward: Yeah, it is satisfying when it works out.
Goldman: So where is all this going to take you next?
Capar: We have aggressive growth goals. Since I started here, we’ve been focusing mainly on operational excellence measures, and we’ve made great strides. We want to become one of the leading quick-turn advanced technology fabricators in the industry. To grow our business, we have a tremendous amount of work in progress including what Jesse mentioned. Three people spent three days at the IPC APEX EXPO spec’ing out equipment. We have placed an order for a second plasma unit. We are close to placing an order for a second automated high-temp lamination press. A via fill machine is next. We will be investing heavily in our business. We have been hiring as well. It has not been easy but we filled a number of operator positions to strengthen our second shift. We are confident of our capabilities and we want to get the word out about Compunetics. We don’t want to be the best kept secret in the PCB industry anymore because there is very little technology that’s out there that Compunetics cannot do.
In general, industry expects this level of technology to come from tier one fabricators like TTM and not from a small- to medium-sized company in Pittsburgh, Pennsylvania. So, we want to get the word out, but again, once you’re confident with the technology and the turn time, we believe there is a real demand in the industry for a high-tech shop that can consistently deliver an on time, high-quality product.
Goldman: Anything to add here, Tim?
Schmitt: A few other things. One of them is that we do have some expertise in large defense antennas. One was for Lockheed Martin. It was a space-based radar and we made 72 tiles. Those tiles, each about 18”X18” were all assembled into one unit and were successfully tested tested by the Air Force. Those were a multilayer flex hybrid, which included the flex and some Rogers material, plus buried resistors. We have other customers that we do antenna work for as well.
Goldman: Do you see much call for embedded components?
Schmitt: Lately we have not been seeing a lot for buried resistor work. We do see a lot for buried capacitors, and we've worked with the buried capacitor materials from Oak-Mitsui, 3M and DuPont. As a matter of fact, our sister division uses buried capacitance material in their product, which we provide to them. There is another market that just picked up for buried resistors, which we can't talk about now, but it has potential. We're also involved with certain customers that use interposers. We do a lot of interposers. They end up at Intel and Intel’s customers and are used in high-speed logic analyzers. The interposers are all fairly complicated. They're usually rigid-flex. They usually have high-speed materials, Nelco 13 SI EP or similar materials. They'll have traces down to two mils to get the impedance they need, and they'll be anywhere from eight to up to 20 layers. Some also have buried resistor layers, and all have high-density via-in-pad outer layers with some of them down to a 0.35-millimeter BGA. I remember one had 17 different controlled impedance values. Those go to a variety of our customers. They're all high-speed, high-value interposers.
Goldman: Thank you. You certainly are doing a lot of interesting things. I hope you will write about it one of these days! Anything else you would like to add?
Capar: I can say I am very happy to be here. Again, what drew me to Compunetics was their legacy of being a world-class shop back in the day that I had tough time competing against. Many years later when the opportunity came up to join Compunetics I jumped on it, and I’m happy I did. I have a broad-based experience in scaling businesses, and I am confident that with my incredible team we will be scaling this business and creating jobs in Western Pennsylvania. You are going to hear a lot of great things about Compunetics in the coming days and months.
Goldman: OK. I’m definitely looking forward to that. Gentlemen, thanks so much for your time.