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AI is pushing hardware to its limits, and the bottleneck isn’t design anymore—it’s materials. Next-generation AI servers aren’t just heavier on layer counts. They demand better materials to handle the speed, heat, and signal integrity requirements of 400G, 800G, and even 1.6T Ethernet systems. Many server motherboards are already 32–36 layers. For the next wave of 1.6T-capable boards, expect 40–50 layers, which must maintain high-frequency performance without degrading signal quality.
The Race for Ultra-low Dk/Df
As Dr. Shiuh-Kao Chiang noted in his technical seminar at HKPCA 2024, at these frequencies, even small signal losses are unacceptable. That’s why demand for ultra-low dielectric constant (low Dk) and low-loss factor (low Df) laminates is skyrocketing. Global leaders Rogers and Panasonic dominate the premium high-speed materials market, but Chinese firms like Shengyi invest heavily to close the gap.
Glass fiber is the biggest constraint. Low-Dk glass is in critically short supply, with Nittobo, AGY, and Taiwan Glass controlling most of the market. Mainland Chinese suppliers are racing to ramp up capacity, but for now, supply is tight.
Extreme Low Loss (XLL): From High-End to Standard
Two years ago, XLL laminates were reserved for bleeding-edge network gear. Today, they’re becoming standard for AI servers and high-performance computing systems because every watt of power lost and every millisecond of latency matters. For example, AI workloads for real-time biomedical analysis simply cannot afford signal degradation.
Figure 3: Adoption curve of XLL laminates in server and HPC boards. (Source: Prismark)
Materials innovation isn’t just about resin systems. Copper foils and glass reinforcements are equally critical.
- Copper: Must balance ultra-thin profiles with excellent conductivity for high-density interconnects
- Glass: Needs to deliver ultra-low Dk while maintaining mechanical stability in 40+ layer builds
Geopolitics and the Supply Chain Shake-Up
Geopolitics are another force reshaping the material landscape. Tariffs, export restrictions, and regional manufacturing strategies are splitting the supply chain. Prismark expects significant regional diversification between 2025 and 2026, with Chinese suppliers aggressively pursuing domestic production of advanced glass fiber and resins to reduce dependence on Japan, Taiwan, and the U.S.
Figure 4: Regional material supply realignment forecast, 2025–2026. (Source: Prismark)
Cross-industry Collaboration A Must
As Chiang noted, AI hardware challenges can’t be solved in isolation, no matter how many tariffs are placed and how much shipping costs are affected. Material science, precision PCB manufacturing, and system-level design must advance together. The most forward-looking players are building cross-industry partnerships–bringing together resin chemists, copper foil suppliers, PCB fabricators, and system integrators to co-develop next-gen materials and processes.
Conclusion
The AI era has turned materials from background players into strategic assets. Whoever controls the supply of XLL laminates, low-Dk glass, and advanced copper foils will control the pace of AI hardware development. For PCB manufacturers, this means one thing: The future is not just about building boards; it’s about mastering the material stack that makes AI possible. This is good news for Chinese and Taiwanese suppliers. For the rest of us, our success will be increasingly reliant on our partnerships with material suppliers.
With AI reshaping demand (Article 1), hardware design (Article 2), and now materials and supply chains (Article 3), the PCB industry is entering a new golden era. Those who innovate across all three fronts will own the future.
This article is based on insights shared by Dr. Shiuh-Kao Chiang of Prismark during his technical seminar at HKPCA 2024 with some editorial discourse based on this article being published in I-Connect007 in 2025. Any omissions are unintentional. The original content was published in the Journal of HKPCA 2025, Q2, No. 94. For more details, visit www.prismark.com or contact the author at edy@e-cio.cn.
