Laminate Suppliers Face Increasing Demands From Customers

Estimated reading time: 4 minutes

As a global laminate supplier with a large product offering, TUC is at the forefront of the growing customer demands that stem from a number of market segments pushing next-generation products. In an interview with Nolan Johnson, TUC North American President Alan Cochrane talks about the company’s shift toward trending areas—including HDI, halogen-free, and RF—and how strategies like the adoption of thinner glass styles have helped make it all possible.

Nolan Johnson: Alan, please give us some background on yourself and TUC.

Alan Cochrane: I’ve been with TUC for a little over eight years, and I’ve been in the industry since 1978. I started in research and development at TRW (now Northrop Grumman). I was on the fabricator side until 2010 when I joined TUC. We’ve seen a substantial amount of growth, including $425 million in 2016, $525 million in 2017, and $630 million in 2018.

TUC has been in business since ‘97, making copper-clad laminates. TUC started with mid- Tg materials and quickly moved up to high Tg as well as halogen-free products in the mid-loss range. Since the marketplace keeps having more and more needs, we moved into low-loss and super low-loss categories. We break things down into a few different market segments: high-speed digital and HDI applications in that marketplace. We also have product offerings for the RF and the millimeter-wave applications as well as a small segment that is the high-Dk specialty materials.

The biggest focus these days is mainly in the high-speed digital and RF areas. And there’s some crossover between the two of them. We have a product offering in the high-speed digital that’s for the 56-Gbps applications that are out there, which is pretty well entrenched. That’s the 12.5–14.5-GHz range that we’ve been servicing with a number of products. It’s an APPE-based product lineup with different fillers, etc. We’ve done a lot of interesting testing with large OEMs to meet their needs.

We are releasing a product soon called T4 for 25–28-GHz applications. The magic number, from an OEM standpoint, seems to be a 0.7dB loss per inch at 25 GHz with a 5-mil trace. So, as we get up into the 25–28-GHz applications, we have to look not just at our dielectric material but also at coppers that are starting to play a very big role in the overall loss of the product.

Johnson: What are some of the market dynamics that you’re currently seeing?

Cochrane: Almost six years ago, it used to be low Dk to try to get thinner. Everything is shrinking and there’s more miniaturization. Packages are getting smaller and smaller. To maintain that proverbial 50-ohm characteristic impedance or 100-ohm differential applications, we wanted thinner dielectrics with lower Dk so that we could maintain 50–100-ohm applications. However, we started getting into too low of a line width with resultant resistance to the overall losses, which became a major problem. Our focus for the last five years has been to look at lower loss for our high-speed digital customers.

Loss is the big driver followed by skew. The skew from trace to trace with differential pairs is determined a great deal by the glass weave that is utilized. What used to be a single-ply construction with a flat glass is evolving into multiple ply. The magic-ply count seems to be about a three-ply construction and to get into 5-mil dielectrics that we’re looking at for a 5-mil trace, that means we have to use a thinner glass.

Now, we’re crossing over to HDI. The 1027 glass—one and a half mils in overall thickness—used to be for laser applications for thin, stacked microvias. Today, we’re using a lot more of that in high-speed digital. Within the last two years, we’ve gone from the standard glass being a 1078, for example, to a 1035 and now down to a 1027. We’re getting thinner and thinner glasses to support that skew requirement as well as the loss requirements now even moving to 1017 and 1010 glass styles.

Johnson: Where do you see TUC’s current sweet spot in your product portfolio?

Cochrane: We have two main areas right now. We’ve gotten very close to the magic number of the 0.70 dB loss per inch at 25 GHz, which is for the next generation of chips that are out there for the 112-Gbps or 400-Gbps switch. That’s the lowest loss material that we have that is not in the PTFE range. We’re getting a lot of traction in that area because of that need.

We’re also seeing a resurgence of halogen-free. With the offering that we have in the halogen-free world, we still have a very low-loss material. We’re seeing a lot more utilization of the super low-loss, halogen-free materials. There may not be a corporate mandate to use halogen-free, but designers are finding that they can get the kind of performance out of a halogen-free that they couldn’t a number of years ago.

Johnson: Does the drive for the halogen-free seem to be customer demand?

Cochrane: Yes, in addition to their ability to have very low-loss and super low-loss materials. Then, we can easily get good performance in the 56-Gbps applications and the 14.5-GHz area. They’re being good corporate citizens. We see demand coming out of Europe, Canada, and North America as well.

To read the full article, which appeared in the May 2019 issue of PCB007 Magazine, click here.