China's PCB Industry Chain Plays a "Low-Profile Trump Card"

October 25, 2025

Taiwanese manufacturers are highly focused on the supply bottlenecks of upstream Copper Clad Laminate (CCL) materials amidst the incoming AI wave. Mainland Chinese manufacturers, meanwhile, are emphasizing the demonstration of their PCB technological capabilities for both cloud and edge AI applications.

Notably, at CPCA Show Plus 2025, not only were high-end products like AI server motherboards, switch boards, IC packaging substrates, and IC test carriers visible, but PCB manufacturers also discreetly exhibited PCB module boards for the CoWoP base layer, tentatively named UHD boards (Ultra High Density).

Previously, reports emerged that NVIDIA is leading the development of a new packaging technology, CoWoP ("Chip-on-Wafer-on-Platform PCB"), which boldly eliminates the ABF substrate used in mainstream packaging architectures, directly packaging AI chips onto the PCB motherboard. This has sparked intense discussion as it threatens to reshape the existing landscape of the advanced packaging supply chain.

In theory, the CoWoP architecture, by forgoing the ABF substrate, could achieve breakthrough advancements in AI chip performance by improving cost efficiency and shortening transmission paths. However, the CoWoP packaging architecture that eliminates the ABF substrate could theoretically help AI chips achieve further breakthroughs in terms of cost-effectiveness and shortening the transmission path. But due to the large span of process technology challenges and the considerable time spent on supply chain collaborative development in the early stage, it is not unanimously favored by the industry in practice.

It is understood that the exhibited CoWoP base layer PCB sample will definitely be based on an HDI board process architecture, combined with a substrate-like PCB (SLP) mSAP wiring process. The current UHD board has roughly 20-30 layers, with an area slightly smaller than the previously industry-rumored 450x450mm design.

Nonetheless, moving from the current stage to mature mass production for CoWoP technology is expected to take at least two years or more, necessary to complete rigorous testing and verification procedures. It is anticipated that customers will adopt the CoWoP packaging architecture incrementally for the Feynman platform, expected around 2028, rather than implementing a one-time, large-scale replacement of the current mainstream CoWoS.

[Chinese PCB manufacturers] possess high confidence in their PCB manufacturing technology but are choosing to low-key display their development achievements in the CoWoP field.

The term "2-step" means there are two layers of laser vias. "Staggered vias" means the two layers of laser vias are offset from each other.

Recently benefiting from the surge in PCB value driven by AI computing power, the PCB supply chain is witnessing a wave of industrial structural transformation. Within the AI PCB manufacturing sector, advanced manufacturers like Shenghong, Shengyi, and Wus have gained first-mover advantages. Other potential suppliers, in their efforts to catch up, are also accelerating their CoWoP technology development, hoping to overtake competitors on this new track.

In stacked vias boards, the two layers of laser vias are aligned on top of each other. This allows for a more compact layout. The inner laser vias must be electroplated and filled flat before the outer laser vias are added. This process makes stacked vias boards more expensive than staggered vias boards.

It is worth mentioning that while a few companies claim to possess the PCB technology required for CoWoP, in reality, some have merely built factories and purchased equipment – things achievable with capital. However, what money cannot quickly accomplish is the cultivation of talent, the mastery of core technology, and the establishment of robust industry connections. The supply chain also confirms that several PCB manufacturers have already received collaboration requirements from NVIDIA and are actively engaged in CoWoP development. Besides the three major PCB makers mentioned above, others include Zhending, Unimicron, and Compeq, along with upstream CCL material suppliers like TUC, Taiwan Union Technology (TUC), and ITEQ. A diversified supplier layout is gradually taking shape.