Plasma ash processes that cause surface damage in porous interlayer dielectric materials (ILDs) result in increased water absorption, permittivity, and metal intrusion. In this study, we employ mono-, di-, and tri-functional alkoxide silylation agents in supercritical CO2 to repair O2 ash damaged low-k methylsilsesquioxane (MSQ) films. Fourier transform infrared spectroscopy (FTIR) was performed using normal incidence transmission and attenuated total reflection (ATR) techniques to highlight differences in silylation efficiency based on agent functionality. Contact angle measurements reveal a significant change in hydrophobicity after functionalization of the O2 ashed samples with multifunctional agents. Atomic force microscopy (AFM) was utilized to determine changes in surface topography after ashing and repair.