Supercritical CO2 (SCCO2) was used to facilitate silylation in repairing oxygen plasma-induced damage during photoresist stripping in porous organosilicate films. Samples with open and closed-pore morphologies prepared by sacrificial-porogen approach were exposed to O 2 plasma to simulate damage. These samples were pretreated with 10% butanol in SCCO2 (wt/wt) and were silylated with 10% trimethylchlorosilane in SCCO2 (wt/wt). The results showed that this technique was effective in repairing plasma damage in films with open-pore morphology but was less effective in closed-pore films. However, the surface hydrophobicity for both films was recovered after treatment.