| Abstract
| - Chemical modification of the buried interfaces between silicon wafers and either polystyrene or poly(methyl methacrylate) (PMMA) with the reagent (tridecafluoro-1,1,2,2-tetrahydrooctyl)dimethylchlorosilane(FDCS) was studied using liquid and supercritical carbon dioxide as the solvent and infusing agent. Abovethe critical point of CO2, FDCS reacts with surface silanols at the SiO2/polystyrene interface to form amonolayer, which was analyzed after removal of the polystyrene film. This is not the case below the criticalpoint, and likely the lower diffusivity and solvent properties of the CO2-swollen film are the causes. Thereaction was much less successful at the SiO2/PMMA interface. We suspect that because of strong hydrogenbonding between PMMA and the silicon substrate, modification of the SiO2/PMMA interface is achievedto only a limited extent.
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