In this work, we study the dilution of Spin-On Glass (SOG) in order to obtain high quality SiO2 films at 200 degrees 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 degrees C is an excellent candidate to be used as insulator on flexible and large-area electronics. (C) 2012 Elsevier B.V. All rights reserved.