Supply Chain Briefing · Published Jan 15, 2025

ABF substrate tightness

Executive briefing: The packaging substrate market remains a chokepoint for AI GPUs and advanced logic as organic build-up films and high-layer ABF cores lag demand. Suppliers and foundries are investing, but most capacity arrives 2025–2026.

• Capacity strain. TSMC acknowledged substrate and CoWoS packaging bottlenecks in mid-2023 and committed to more than doubling advanced packaging capacity by end-2024 to support AI accelerators.
• Material expansion. Ajinomoto plans to boost production of its ABF build-up film by roughly 60% by fiscal 2025 to relieve shortages, following ¥90 billion in planned investments.
• Outlook. TrendForce notes that tight ABF availability will persist through 2025 because AI servers and high-bandwidth memory packages consume larger panels and multilayer cores, outpacing incremental debottlenecking.

Operational actions

• Secure multi-year substrate agreements with tier-1 suppliers (Unimicron, Ibiden, Shinko) tied to forecast visibility and tooling co-investments.
• Align package design rules with supplier panel capabilities to avoid late-stage respins when migrating to larger body sizes.
• Track CoWoS and substrate readiness on the same critical path as die taping to prevent schedule slips in AI accelerator ramps.

Sources

• Reuters — TSMC to more than double advanced packaging capacity by end-2024 (July 20, 2023)
• Nikkei Asia — Ajinomoto to boost key chip-material production by 60% (August 8, 2023)
• TrendForce — ABF substrate supply remains tight as AI server demand surges (November 6, 2024)

Zeph Tech monitors substrate lead times, CoWoS slots, and panel conversion risks for AI hardware teams.