That's not what the Seah/Dench penetration depth data is for. It is for correcting relative intensities of peaks from a homogenous material so that the stoichiometric coefficients of an element whose photoelectrons have a longer escape path don't get exaggerated.

There are, however, approaches to measure the film thickness from XPS intensities like this one (which I've never used, though):

Article Thickogram: A method for easy film thickness measurement in XPS

Generally, I would prefer ellipsometry (for dielectrics and semiconductors) or 4-point probe measurements (for metals) for thickness measurements.

@Jürgen Weippert Thank you very much