ABF Substrates – Signs of a Mainstream Demand Recovery?
An enabler of AI server chip packages and a window into mainstream market demand
Just below the chip sits the PCB’s sexier brother: the IC substrate.
Serving as a bridge between the ultra-fine traces of the chip and the comparatively large traces of the PCB, the IC substrate enables communication between these two worlds.
There are two main types of IC substrates: BT substrates, typically used in consumer electronics like smart phones, and ABF substrates, which are used in PCs and larger server chip packages. The distinction comes from the type of insulating film used - BT (bismaleimide triazine) or ABF (Ajinomoto Build-up Film).
ABF substrates were first developed by Intel using insulating materials from Ajinomoto, a company best known for food chemicals like MSG. Years ago, Ajinomoto recognized that its chemical formulations had applications in the semiconductor industry - and that insight has since proven prescient.
A Dual-Engine Market
The market for ABF substrates operates on two engines.
On one side, high-volume PC demand accounts for the majority of ABF substrate consumption. On the other, low-volume but high-complexity AI server packages (like TSMC’s CoWoS & server switches) are expanding the total addressable market (TAM) and driving demand for more advanced ABF substrates.
While much attention is given to the evolving dynamics of AI server packaging (as we discussed during our Spaces call last week), this note focuses on another critical signal: recent data coming out of Taiwan and what it suggests for ABF substrate demand, and mainstream demand generally.
What the Taiwan Data Tells Us
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