Who makes packaging & bonding equipment for AI data centers

This is the equipment layer behind advanced packaging (2.5D/3D advanced packaging): the hybrid-bonding, thermo-compression bonding, dicing and grinding, molding, and inspection and metrology tools that OSATs and foundries use to physically build and check a finished package. It doesn't touch the die design at all — it's capital equipment sold to whoever is doing the packaging work, whether that's the foundry itself or a third-party OSAT — and its order book is a forward indicator for future packaging capacity additions rather than current shipment volume. Investors get a more fragmented but arguably clearer read from this sub-layer than from packaging capacity itself: equipment order backlogs are disclosed on a normal capital-equipment reporting cycle, and a given tool vendor's exposure to HBM-specific bonding equipment (as opposed to general-purpose semiconductor equipment) is usually identifiable. Qualification cycles for a new tool at a customer's line are long, which tends to lock in incumbent equipment suppliers once a packaging process is established, but a shift to a new bonding technique (such as hybrid bonding gaining share over thermo-compression) can reshuffle which equipment vendors benefit.