Porosimetry measurements on low dielectric constant-thin layers by coupling spectroscopic ellipsometry and solvent adsorption-desorption

Abstract

Ellipsometric measurements are carried out on different commercial ultra low-K mesoporous thin films under several solvent vapor pressures. In a first step, both open porosity and skeleton refractive indices are estimated using linear and Lorentz-lorenz laws. In a second step, adsorption-desorption isotherms of selected solvents, giving refractive index as a function of the relative pressure, are acquired. Pore size distributions (PSD) are calculated. The effect of the nature of the adsorbate on the PSD is also discussed. © 2005 Springer Science + Business Media, Inc.