Inside the AI Hardware Boom: Servers, Substrates and Advanced Packaging

Estimated reading time: 3 minutes

AI is rewriting the hardware playbook, marrying complex software and algorithms to run and improve machine and equipment operations. Sorting through, managing, and utilizing massive amounts of data takes tremendous data storage and processing power. Enter the new generation of supercomputers and data servers. The data servers being built today are not your momma’s server, as they say.

As discussed in article one of this series, AI server shipments more than doubled, jumping from under 400,000 units to over 1 million in 2024. Each of these machines is far more complex and PCB-intensive than traditional servers, from massive 22-layer any-layer HDI motherboards to accelerator card carriers packed with GPUs and high-bandwidth memory (HBM), containing between $1,000–$2,000 worth of PCBs in a single unit.

The Market Explosion

The knock-on effect for the wider server and storage market has been dramatic. In 2023, the global server and storage market stood at $172 billion. By the end of 2024, that figure had ballooned to $254 billion, with projections of $431 billion by 2028. This growth is driven by hyperscale data centers and new deployments in defense, autonomous vehicles, robotics, and biomedical computing, all of which need AI-optimized hardware.

HDI Boards Lead the Charge

AI servers have triggered a boom in high density interconnect (HDI) boards. In 2024, HDI boards grew 17.8%, the fastest among PCB categories. With half of 2025 in the rearview mirror, it sometimes seems like HDI is all we discuss in PCB fabrication. HDI and UHDI technology can deliver tight interconnects, high signal integrity, and complex stack-ups in a relatively small footprint. Many AI mainboards use hybrid architectures–a combination of 20–30 traditional multilayer core layers for power distribution and two to eight HDI layers for ultra-dense signal routing.

Substrates: ABF Stumbles, BT Holds Strong

After 2024, not every segment was thriving. ABF substrates, the workhorse for advanced packaging, suffered a sharp correction in 2024 after years of rapid expansion. Overcapacity and price competition dragged down revenue for leading suppliers within Ibiden, with a decrease of 18%, and Nanya PCB, a decrease of over 20%.

In contrast, BT-type substrates combining BT resin with more traditional glass fiber reinforcement outperformed expectations, buoyed by their role in high-performance computing and automotive electronics.

Halfway through 2025, the research and development of advanced materials remains an area of intense interest and activity, though the solutions that will go the distance remain to be proven out. The term and concept of “advanced packaging” as an offshoot of electronics manufacturing and how that is affecting PCBs and the interconnect piece of more complex electronic product solutions has started to pick up steam in industry engineering and technical circles, something only expected to grow.

Packaging Gets Super-sized

If there’s one phrase that defines packaging in 2024, it is “bigger and more complex.” NVIDIA’s Blackwell GB200 package spans 81×75 mm, integrating two GPUs and eight HBM modules. By 2027, package sizes could reach 100x100 mm or larger, creating enormous engineering challenges.

To handle this, NVIDIA, along with AMD and Intel, relies on TSMC’s CoWoS (Chip-on-Wafer-on-Substrate) packaging technology. This approach combines ABF substrates with multi-chip fusion, enabling massive computational density. Intel’s EMIB (Embedded Multi-Die Interconnect Bridge) offers an alternative path to multi-chip integration, but the goal is the same: fuse more chips into larger, denser packages.

The Unseen Heroes: PCB Fabricators

Behind every AI chip and server is a PCB supplier rising to the challenge. Chinese companies like WUS, Gold Circuit (Taiwanese), Shengyi, and Victory Giant saw revenue growth exceeding 30% in 2024, driven by demand for high-layer-count boards in servers and networking equipment. These aren’t just bigger boards, they’re more technically demanding, requiring tight tolerances, sequential lamination, and advanced HDI processing.

Conclusion: Bigger, Faster, Smarter

AI servers are supercomputers in a rack, and their rise is transforming the PCB industry. From hybrid HDI multilayers to supersized CoWoS substrates, hardware design is evolving at breakneck speed. For PCB manufacturers, it’s a race to keep up, and those who can deliver the most advanced boards will claim the lion’s share of this new golden market.

Stay tuned for the final article in this series,“Materials & Manufacturing for the AI Era: The Next PCB Frontier.”

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. For more details, visit www.prismark.com or contact the author at edy@e-cio.cn.