Advanced run-to-run controller in semiconductor manufacturing with real-time equipment condition: APC: Advanced process control; AM: Advanced metrology

Abstract

Run-to-Run (R2R) control has become a common process regulating approach in the semiconductor industry. Conventionally, key process parameters are regulated with respect to the measured metrology data. However, wafer quality can be affected by complex factors related to equipment condition. The steady progress of information technologies enable us to collect and handle larger amounts of data, open new perspectives to explore the interactions between FDC (Fault Detection and Classification) data and product quality, i.e., wafer metrology, which should be considered simultaneously for developing improved R2R controllers. In this paper, the equipment condition is explicitly modeled and integrated into the core of a R2R controller, in order to accommodate this critical aspect of the system in deriving the control law, in order to reduce process variability in more effective way. Therefore, a new R2R control framework is proposed, which is called: Controller with Real-time Equipment Condition (CREC). The effectiveness of the new control strategy is demonstrated and validated using the case study of a Chemical-Mechanical Polishing (CMP) process, in collaboration with our industrial partner.