efem (equipment front end module)

EFEM (Equipment Front End Module) is a mini-cleanroom at the tool front with a robot for handling wafers between pods and process chambers. **Purpose**: Maintain ultra-clean environment at wafer handling point. ISO Class 1-3 conditions. **Components**: Enclosure with HEPA/ULPA filtration, atmospheric robot, wafer handling robot, load ports, aligner. **Pressure**: Positive pressure inside EFEM relative to fab ambient. Clean air flows outward at any opening. **Robot function**: Transfer wafers from FOUP to aligner to load lock or process chamber. Precise, clean handling. **Environmental control**: Filtered laminar flow, temperature and humidity control, particle monitoring. **Wafer flow**: FOUP at load port, robot picks wafer, moves to aligner, then to load lock or direct to tool. **Interface**: Standard interface to tools from any manufacturer. Modular design. **N2 environment**: Some EFEMs operate with nitrogen fill for sensitive materials. **Footprint**: Adds space in front of tool, but essential for 300mm wafer processing. **Manufacturers**: Brooks, RORZE, Hirata, JEL, Genmark.