Reconstruction of grating parameters from ellipsometric data

This paper presents specific experimental ellipsometric data fit of dielectric 2D grating, which can be characterized as very shallow structure. The grating pattern is of squared shape, with sharp edges and depth to period ratio about 1/1000. The rigorous coupled wave analysis (RCWA) was used for characterization of grating response on optical wavelengths. Boundary conditions were formulated using transfer matrix method. Material parameters of the patterned dots are supposed to be known from additional experiments. The task of the fit si to find unknown thickness of all parts of dots.