RFID (Radio-Frequency Identification) tags attached to FOUPs (Front Opening Unified Pods) enable automated wafer lot tracking throughout the 300mm semiconductor fab without manual scanning or line-of-sight requirements.

How It Works

An RFID tag (passive or active) is embedded in each FOUP carrier, storing the carrier ID and optionally lot data. Readers are installed at load ports, stockers, AMHS rail junctions, and tool interfaces. When a FOUP arrives at any reader location, the carrier ID is automatically read and reported to MES. Unlike barcodes, RFID reads through plastic FOUP material without requiring precise alignment.

Fab Applications

The AMHS (Automated Material Handling System) reads RFID to route FOUPs to the correct destination. At the tool load port, equipment reads the carrier ID via E87 (GEM300) and requests processing instructions from the host. Stocker inventory systems track all FOUPs with exact shelf locations. This provides real-time WIP visibility—the location of every lot in the fab for MES and scheduling systems.

RFID vs. Barcode

RFID: Automatic, no line-of-sight needed, faster, works perfectly in cleanroom environments. Higher cost per tag. Barcode: Requires manual scanning or precise alignment. Lower cost. Still commonly used for wafer-level identification.