We used azimuthally-resolved spectroscopic Mueller matrix ellipsometry to study a periodic silicon line structure with and without artificially-generated line edge roughness (LER). Grating profiles were determined from multiple azimuthal configurations, focusing the incident beam into a 60 µm spot. We used rigorous numerical modeling, taking into account the finite numerical aperture and determining the profile shape using a four trapezoid model for the line profile. Data obtained from the perturbed and unperturbed gratings were fit using the same model, and the resulting root-mean-square error (RMSE) values were compared. The comparison shows an increase in RMSE values for the perturbed grating that can be attributed to the effects of LER.
Proceedings Title: Frontiers of Characterization and Metrology for Nanoelectronics 2011
Conference Dates: May 24-26, 2011
Conference Location: Grenoble, -1
Pub Type: Conferences
Diffraction grating, Ellipsometry, Line edge roughness, Mueller matrix, Multi-azimuth method