Measurement and analysis algorithm for sub-30 nm patterns of hexagonal arrays in microphotography

Measurement is a critical aspect of advanced lithography, particularly for evaluating process capabilities in sub-10 nm technology nodes. Traditional manual measurement methods for Scanning Electron Microscopy (SEM) images lack robustness and are inadequate for large-scale analysis, especially for complex 2D features such as dislocations in hexagonal array patterns. To address these limitations, a contour-based algorithm has been developed for measuring Critical Dimension (CD), pitch, and dislocations in hexagonal arrays. By generating virtual layout based on measured CD and pitch, the algorithm enables detailed analysis of placement errors and provides insights into pattern regularity and symmetry. This approach has been verified on SEM images of hexagonal arrays with a pitch of approximately 30 nm, demonstrating its effectiveness in supporting advanced manufacturing process evaluation.