Semi E47.1
SEMI E47.1 defines the FOUP (Front Opening Unified Pod) itself for 300 mm wafers — its outer dimensions, its front door and latching mechanism, its internal slot pitch and wafer-support geometry, and its kinematic-coupling feet — the physical object that sits on top of the SEMI E15 load port interface and actually carries the wafers. Where E15 standardizes the docking interface a carrier mates with, E47.1 standardizes the carrier itself: a sealed, front-opening box holding 25 wafers in precisely spaced slots, designed so its internal micro-environment stays cleaner than the fab's own cleanroom air, opened only by a tool's front-opening mechanism rather than by hand.
The FOUP's sealed, front-opening design exists specifically to decouple wafer cleanliness from cleanroom cleanliness, which is the economic breakthrough that made 300 mm fabs viable in the first place — maintaining an entire cleanroom at the particle-count level a bare wafer needs is dramatically more expensive than maintaining that level inside a small sealed pod, so 300 mm fabs shifted the ultra-clean requirement from the whole room down to the FOUP's internal volume, letting the surrounding cleanroom run at a relatively looser (and far cheaper) particle specification. This only works because E47.1 standardizes the door-opening interface precisely enough that a tool's front-opening mechanism can engage any compliant FOUP's latch and remove its door without ever exposing the wafers to the room air outside — the moment that seal is standardized loosely, the whole cost argument for sealed-pod wafer transport collapses.
SEMI E47.1 and SEMI E15 are two halves of the same physical system — E15 is the load-port docking interface standardized once for any compliant carrier, and E47.1 is the carrier itself standardized to mate with that interface, which together are what lets any 300 mm FOUP from any compliant manufacturer dock on any compliant tool's load port and have its wafers reliably removed in the exact slot positions SEMI E90's substrate tracking expects.