Resonac Holdings — AI supply-chain exposure

Resonac, the company formed from Showa Denko and Hitachi Chemical, is a materials supplier that sits quietly underneath the most advanced part of chipmaking. It makes the packaging materials and the chemical-mechanical polishing slurries used to planarise wafers between fabrication steps, alongside the process chemicals and gases that fabs and packaging houses consume. None of this is a finished chip; it is the consumable substrate on which everyone else's silicon is built, refined, and assembled into a working accelerator.

Its structural hook is that advanced packaging — stacking logic and memory into a single module — is now the binding constraint on AI accelerators, and it runs on specialised materials that only a handful of suppliers qualify to make. Once a slurry or a packaging film is designed into a process, it is slow and risky to swap out, so the incumbent holds durable, quiet pricing power. The model places Resonac mid-chain because it is a chemistry supplier feeding foundry and packaging, not a name most buyers ever see.