Characterization of III-V periodic structures by spectroscopic ellipsometry and grazing X-ray reflectance

Spectroscopic Ellipsometry (SE) and Grazing X-ray Reflectance (GXR) techniques are applied on a III-V periodic epitaxial structures in order to extract accurately structural informations. Thickness informations are obtained directly from Fourier transformation of the GXR spectra and confirmed by simulation of the reflectance curve. Compositions are deduced from SE regression using GXR thickness as input values. Using this method it was possible to detect g reduction of the density of the top layers. This layer imperfection is important to deduce accurate reflectance properties for the same structure