Physical surface adsorption and Molecular Surface Fractal Analysis (MFSA) detected with Spectroscopic Ellipsometry

It is known for years that surface adsorption/desorption can be studied by in situ Spectroscopic Ellipsometry (SE). The physical adsorption of water or other small adsorbate molecule species on the surface of non-porous materials, gives rise to a Type II isotherms which can be measured with sufficient accuracy by SE. The paper reports on recent highlights of this promising application of SE for Molecular Surface Fractal Analysis (MFSA) with a high sensitivity. It is reconsidered with the fractal description of surfaces. The adsorption theories including the effect of fractal properties of thin films surfaces have been recently reviewed and corresponding models can be specifically applied to SE analysis. Within the concept of the surface fractal properties, the study of surface adsorption provides interesting parameters such as dimensionality and surface energy parameters to be correlated with other instrumental observations. Some examples are presented and discussed.