Nano-Meter Resolution Line-Offset Detector Arrays (LODAs) for Pattern Monitoring in EUV Lithography System

A novel line-offset detector array (LODA) is demonstrated for the first time, which can resolve projected patterns in extreme ultraviolet (EUV) scanners for advanced integrated circuit (IC) processes. Fine layout patterns on the projected plane can be truthfully reconstructed by the uniquely designed line-offset array. With nano-meter spatial resolution, the on-wafer battery-less detector array can be read out offline through wafer-level tests. The LODA provides a new direction of nano-meter pattern monitoring that helps maintain stability in EUV lithography systems for CMOS nodes beyond 5 nm.