Scatterometry evaluation of focus-dose effects of EUV structures

CD and shape control of extreme ultraviolet lithography (EUVL) structures is critical to ensure patterning performance at the 10 nm technology node and beyond. The optimum focus/dose control by EUV scanner is critical for CD uniformity, and the scanner depends on reliable and rapid metrology feedback to maintain control. The latest advances in scatterometry such as ellipsometry (SE), reflectometry (NISR), and Mueller matrix (MM) offers complete pattern profile, critical dimensions (CD), side-wall angles, and dimensional characterization. In this study, we will present the evaluation results of CD uniformity and focus dose sensitivity of line and space EUV structures at the limit of current ASML NXE 3100 scanner printability and complex 3D EUV structures. The results will include static and dynamic precision and CD-SEM correlation data.