The AI revolution is running into a critical supply bottleneck, and it's happening in a component you've likely never heard of: the ABF substrate.
So, what exactly is an ABF substrate? Think of it as a sophisticated, multi-layered circuit board that serves as the foundation for high-performance chips, like the GPUs that power AI. As AI models become more powerful, these chips require larger and more complex substrates to connect all their intricate parts. The demand for these has exploded, but the supply simply cannot keep up.
The root of this imbalance is a powerful 'demand shock' driven by the AI industry's relentless pace. First, companies like Nvidia are continuously releasing more powerful chip platforms, such as Blackwell and the upcoming Rubin, which require increasingly larger and more advanced substrates. Second, major chip foundries like TSMC are operating at full capacity, confirming that demand for the advanced packaging services that use these substrates remains extremely high for the foreseeable future.
However, the real problem lies on the supply side, which is constrained by two major bottlenecks. The first is the core material itself, a special insulating film called Ajinomoto Build-up Film (ABF). A single Japanese company, Ajinomoto—yes, the same one famous for food seasonings—has a near-monopoly on this critical film. While Ajinomoto is investing in new facilities, building them takes years, offering no short-term relief for the current shortage.
Adding to the pressure is a second bottleneck in another key ingredient: a high-performance fiberglass cloth known as T-glass. This material is essential for the substrate's structural stability and electrical performance. Shortages of T-glass are now a primary factor delaying the expansion of ABF substrate production, pushing timelines back by an estimated 6 to 12 months.
With demand soaring and supply choked by these material shortages, the outcome is a classic supply-demand squeeze. Analysts predict this supply gap will persist through 2027 and may even worsen. For the companies that manufacture ABF substrates, this situation provides significant pricing power, with price hikes expected to begin in the second half of 2026. For the broader tech industry, it signals potential delays and rising costs for building the next generation of AI infrastructure.
- ABF Substrate: An essential, high-performance circuit board base used for connecting advanced semiconductor chips.
- Advanced Packaging: The process of assembling and connecting multiple chips together in a single package to improve performance and efficiency.
- T-glass: A special type of low-dielectric fiberglass cloth used in substrates to ensure signal integrity at high speeds.