Driven by the continuous demand for increased functionality in integrated circuits, the trend toward higher levels of integration has led to the increasing adoption of three-dimensional structures in order to gain more functionality from a specific area. As design transitions from planar layouts to increasingly complex three-dimensional architectures, precise dimensional characterization becomes essential.  

In 2D trench applications, critical parameters such as linewidth, depth, sidewall angle, profile shape, and bottom curvature directly impact etch performance, pattern transfer, and device reliability. For advanced 3D structures—including high-aspect-ratio features in NAND, 3D-DRAM memory stacks and advanced packaging—metrology must capture complex geometries throughout the process flow without damaging the wafer.  

Together, 2D and 3D characterization metrologies empower process engineers to identify variation early, control critical dimensions, optimize process windows, and ensure that increasingly intricate device structures meet performance and yield requirements.