Extreme W scatterometry using radiation in the extreme ultraviolet photon energy range, with wavelengths around 13.5 nm, provides direct information on the performance of EUV optical components, e.g. EUV pho­ tomasks, in their working wavelength regime. Scatterometry with horizontal diffraction geometry, parallel to the grating lines (conical), and vertical scattering geometry, perpendicular to the lines (in-plane), was performed on EUV lithography mask test structures. Numerical FEM based simulations, using a rigorous Maxwell solver, compare both experimental set-ups with focus on the sensitivity of the diffraction intensities particularly with respect to the side wall angle.

Date Published: 13 May 2013
PDF: 10 pages
Proc. SPIE 8789, Modeling Aspects in Optical Metrology IV, 878905 (13 May 2013); doi: 10.1117/12.2020487

Published in SPIE Proceedings Vol. 8789:
Modeling Aspects in Optical Metrology IV
Bernd Bodermann; Karsten Frenner; Richard M. Silver, Editor(s)