Metrology and inspection tools that measure and check wafers so fabs can manage yield, sitting between equipment makers and leading-edge logic fabrication. Availability is set by tool supply from a concentrated set of vendors against fab demand for yield-management capacity.
A sustained tight read means demand for metrology and inspection tools is running ahead of what the equipment makers can deliver, so fabs queue for inspection and measurement capacity needed to manage yield on leading-edge logic. The read is vendor revenue growth: it tracks how hard that tool demand is running, not delivered tool capacity directly. Relief arrives only as vendors expand production and lead times ease, over quarters rather than a single order cycle.