TSMC CoWoS Boom Lifts Substrate-Like PCB Makers Into AI Supply Chain

TSMC is racing to double advanced packaging capacity again in 2025 after a near-tripling of CoWoS output last year, as NVIDIA and AMD AI accelerators absorb every wafer it can package. The buildout, spanning new fabs in Chiayi and Tongluo, is tightening the market for IC substrates and pulling substrate-like PCB (SLP) makers directly into the AI hardware chain.

On its January earnings call, TSMC told investors advanced packaging revenue would more than double in 2025, following growth above 60% in 2024. Supply-chain reports put CoWoS capacity near 35,000 wafers per month at end-2024, with targets above 70,000 by late 2025. Chairman C.C. Wei has repeatedly warned capacity stays tight through 2026. Each AI package consumes a large silicon interposer and an oversized ABF substrate carrying several times the area and layer count of a conventional server board, so packaging expansion translates almost one-to-one into substrate demand.

That demand is redrawing the map for substrate and SLP producers. Unimicron, Nan Ya PCB, Kinsus and AT&S are adding ABF capacity, while Shinko and Ibiden remain fully booked on interposer-class product. For substrate-like PCB specialists built around mSAP fine-line processes for smartphones, the overlap is strategic: the same exposure and plating capability serves network switches, edge-AI modules and panel-level packaging pilots. With consumer SLP demand soft since 2023, AI and HPC orders now anchor utilization and capex plans across Taiwan, Austria and mainland China lines. Buyers should expect allocation and firm pricing on high-end capacity through at least 2026, and earlier engagement on fine-line roadmap alignment.

LT CIRCUIT produces substrate-like PCBs alongside HDI any-layer, IC substrate class and high layer count boards, supporting OEM teams designing edge-AI accelerators, 800G optical modules and compact power electronics where fine-line routing and tight impedance control determine performance. Engineering samples and quick-turn builds are available for qualifying designs.