Tower Semiconductor Ltd. — AI supply-chain exposure

Tower Semiconductor is an Israeli specialty foundry — it manufactures chips to order, but rather than chasing the leading logic nodes it focuses on differentiated platforms, chief among them an open silicon-photonics process used to build the optical engines inside high-speed transceivers. It sits at the producer end of the silicon-photonics layer, fabricating the light-handling chips that let AI networks move data as photons instead of electrons.

Its structural hook is that open-foundry model: transceiver and optical-engine designers who lack their own fabs need a merchant photonics platform, and Tower runs one of the recognised ones. As AI interconnect shifts from copper toward optics, demand flows to the fabs that can print these devices at volume. The model places it in the chain because silicon photonics is a widening bottleneck, though its weight reflects a specialist foundry role rather than mainstream-logic centrality.