The Physical Layer

AI and energy infrastructure, explained plainly.

Companies

TSMC

On the map: Memory · The network between chips · Chips and the factories that make them

Named in 3 pieces. Each entry below is that piece's own description of what the company makes, from its exposure map.

  1. The base die

    TSMC and Samsung's foundry make logic base dies for HBM4.

    Memory, not maths, sets the pace of AI, so the biggest buyer now designs it · 31 October 2026

  2. Inside the plug

    Marvell and Broadcom make optical DSPs; Lumentum and Coherent, lasers. Innolight, Eoptolink and Fabrinet build transceivers. TSMC and SPIL make co-packaged engines.

    How ten thousand chips talk: the glass stays, and the plug survives its replacement · 4 September 2026

  3. Factories and packaging

    TSMC makes and packages AI chips. Ibiden and Unimicron make package substrates.

    The chip supply chain's slow parts are sold years before they are made · 14 July 2026

This maps who operates in each layer. It is not a recommendation, and naming a company is not a view on its shares. Personal research, not investment advice.