In my company, we have developped a mehod to measure the surface area, porosity , pore size distribution, thickness , and n&k of thin films like TiO2 on any substrate, like TiO2 on ITO. We can measure at the same time the parameter of the TiO2 and also check ITO characteristics. It is called Ellipsometry porosimetry , it is a method based on the well know ellipsometry method, non contact , optical method and the also well known gas adsorption. It does require any scratch of the film , no vaccum, no low temperature. It is also non desctructive.
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