mes (manufacturing execution system)

A Manufacturing Execution System is the **central software platform** that manages, monitors, and tracks all wafer fabrication operations in real time. It's the backbone of fab automation and production control. **Core Functions** **Lot Tracking** follows every lot from start to finish—current location, step, status, and complete history. **Recipe Management** ensures the correct process recipe runs on the correct tool for each lot. **Dispatching** generates prioritized work lists for each tool based on dispatching rules. **Q-Time Enforcement** alerts and escalates when lots approach critical queue-time limits. **Data Collection** logs all process parameters, timestamps, operator actions, and equipment events. **Key Integrations** The MES connects to equipment via **SECS/GEM or GEM300 protocols** for automated lot processing. Process data flows to **SPC systems** for real-time monitoring. Lot status feeds **scheduling systems** for capacity and delivery forecasting. **Yield management** links inline and end-of-line test data to lot processing history. **Major MES Vendors** • **Applied Materials** (PROMIS/Fab300): Widely used in 300mm fabs • **Siemens** (Camstar): Common in packaging and specialty fabs • **IBM** (SiView): Legacy system still used in some fabs