Published online by Cambridge University Press: 01 February 2011
We propose and demonstrate experimentally a structural characterization technique for ultra-low-dielectric-constant thin films with periodic porous structures [1-3] by employing X-ray diffraction / scattering measurements. The analytical approach that we propose here takes into account specular reflection, incoherent scattering from random distribution of electron density, and coherent scattering from periodically modulated distribution of electron density. From the analysis, inter-pore distances and pore diameters in the directions perpendicular and parallel to the film surface are determined with which the film porosity is calculated. Thus obtained porosity is then used to discuss the film density and dielectric constant in comparison to those of non-porous reference sample.