Silica thin films have been deposited on silicon substrates by electron beam evaporation using MCM-41 pressed powders as targets. Through X-ray diffraction, FT-IR (Fourier transform infrared) spectroscopy, SEM (scanning electron microscopy) and AFM (atomic force microscopy) techniques, the structure, composition and morphology of resulting films have been established. Transparent and stoichiometric silicon dioxide thin films with very smooth surfaces, an apparently well-defined order and orientation parallel to the substrate surface have been obtained. The low values of the refractive index, the surface pore size distribution and the smoothness of these films, show the possibility to use the electron beam evaporation using MCM-41 materials as targets to manufacture porous silica thin film for applications in optoelectronics and low k dielectrics for microelectronic devices.