Silicon and phosphorus ions were implanted into Spin-On-Glass (Sol-Gel) SiO2 films and were found to modify the material properties. Two SOG types, polysiloxane andsilicate, were ion-implanted with doses in the 5 × 1014 − 1.65 × 1016cm−2range and energies of 40keV - 190keV. The implanted SOG on silicon samples were characterized by ellipsometry, infra-red spectroscopy, etching and capacitance measurement of aluminum/SOG/silicon devices. The results indicate that the polysiloxane type SOG shrinks due to the implant and its effective refractive index increases. The ion-implant of the polysiloxane SOG also changed its structure and composition as seen by the variations of the infra-red transmission spectrum, etching characteristics, and dielectric constant. Silicate SOG exhibits less shrinkage due to the implant but its other characteristics show dependence on the dose similar to that of the polysiloxane SOG.