In this work, we study the dilution of Spin-On Glass (SOG) in order to obtain high quality SiO₂ films at 200 °C, with optical and electrical characteristics similar to those of the thermally grown SiO₂. For the production of SiO₂ films we used 2-propanol and deionized water (DI) as diluents for the SOG and we compared the electrical and optical film properties with those of the films obtained from undiluted SOG. From Fourier transform infrared spectroscopy we observed a considerable reduction of Si-OH (920 cm⁻¹), O-H (3490 cm-⁻¹) and C-H, C-O bonds (1139 cm⁻¹) in the films produced from SOG diluted with DI. Besides the above, the insulator breakdown field was approximately 21 MV/cm, the refractive index and the dielectric constant were close to those of the thermally grown SiO₂. Our results suggest that the film produced from SOG diluted with DI and cured at 200 °C is an excellent candidate to be used as insulator on flexible and large-area electronics.