Ajinomoto, the Japanese company that first commercialized monosodium glutamate in 1909, holds more than 95% of the market for Ajinomoto Build-up Film (ABF), the insulating film used in high-performance semiconductor package substrates, according to figures from the company itself. Materials startup Thintronics has now set out to challenge that near-monopoly, and surging AI demand is widening the opening for a challenger.

The target market is niche but structurally critical. ABF sits inside advanced package substrates — the layered interconnect structures that carry signals between a die and a printed circuit board. Every high-performance chip package that uses this insulation route currently depends, almost without alternative, on a single supplier whose original business was food seasoning. That concentration is the story. A second qualified source would change procurement risk calculations across the packaging supply chain.

How dominant is Ajinomoto's position?

By the company's own account, its share exceeds 95%. No other vendor holds a comparable qualified position in build-up film for high-performance substrates. Ajinomoto entered the materials business from its food-science base after developing the epoxy-based film in the 1990s, and the product has since become a de facto standard in advanced packaging.

For R&D and sourcing managers, the significance is straightforward: a sole-source material at the heart of the AI hardware buildout. Any capacity constraint, allocation decision or price move by one supplier propagates directly into substrate makers' delivery schedules and chipmakers' packaging costs.

Why is AI demand widening the opening?

The surge in AI accelerator production has driven demand for advanced package substrates — and therefore for ABF — sharply upward. Rapid volume growth strains a single-supply chain and gives substrate manufacturers a concrete reason to qualify an alternative. Tightness in supply is what converts a theoretical second-source strategy into an active procurement priority.

This is the commercial window Thintronics is positioning itself inside. The startup's bet is that materials qualification cycles, which normally favor incumbents, tilt toward a new entrant when buyers face allocation risk on a critical input.

What should buyers and R&D managers watch?

The relevant questions for anyone assessing this challenge are the standard ones for any materials substitution in semiconductor packaging:

• Qualification status: has any major substrate manufacturer formally qualified the challenger's film, and on which platform generations?
• Measured performance: dielectric properties, thickness uniformity and reliability data at production scale, not lab-scale claims.
• Capacity: committed production volume and timeline, since qualification without volume does not de-risk supply.
• Funding: who is backing the challenge and whether capital covers the multi-year qualification period.

The market share figure of over 95% comes from Ajinomoto itself, not an independent audit — a reminder that even the baseline numbers in this story are vendor-supplied and warrant the same scrutiny as any challenger's claims.

Is a real shift likely?

Incumbency in semiconductor materials is durable because qualification cycles are long and switching costs are high. Yet sole-source dependence during an AI-driven capacity race is precisely the condition under which buyers fund alternatives. Whether Thintronics converts that opening into qualified design wins will depend on performance data and manufacturing scale it has yet to demonstrate publicly; surging AI demand has widened the door, and the industry will be watching who walks through it.

By Sophie Lindqvist