Capacity forecast model for control and dummy wafers

Tool capacity planning is a frequent task in semiconductor wafer fabrication plants. Various control and dummy wafers (C/D wafers) used to enhance product quality and process stability become increasingly important to fab performance. The capacity required to fabricate complex C/D wafers must be taken into consideration in the tool investment plan. Inaccurate capacity forecast of C/D wafers results in tool investment surplus or shortage. This paper describes a successful methodology to establish capacity forecast model for C/D wafers. The proposed model presents the solution to be explored effectively and has demonstrated a capability superior to the current planning method in wafer fabrication plants