Analytical Linescan Model for SEM Metrology

摘要

Critical dimension scanning electron microscope (CD-SEM) metrology has long used empirical approaches to determine edge locations. While such solutions are very flexible, physics-based models offer the potential for improved accuracy and precision for specific applications. Here, Monte Carlo simulation is used to generate theoretical linescans from single step and line/space targets in order to build a physics-based analytical model. The resulting analytical model fits the Monte Carlo simulation results for different feature heights, widths, and pitches. While more work is required to further develop this scheme, this model is a candidate for a new class of improved edge detection algorithms for CD-SEMs.