Nanoindentation was used to probe the mechanical response of mesoporous silica films as a function of processing treatment. A contrasted behaviour appears between low temperature processed films which retain the templating agent and are thus little compressible, and high temperature processed films, which are more condensed and also exhibit high porosity. We suggest that the behaviour of the former is dominated by shear flow, at least above a given threshold, while the latter are characterized by a yield strength in compression as is commonly found in porous materials. The response to indentation allows fast qualitative comparison of mechanical responses: in the present work, we show that a fast UV-Oj treatment results in mechanical properties which are undistinguishable from a much more cumbersome high temperature heat treatment.
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