Embodiments of the present invention provide hydrogen-free dielectric films and methods of fabrication. A hydrogen-free precursor, such as tetraisocyanatosilane, and hydrogen-free reactants, such as nitrogen, oxygen (O2/O3) and nitrous oxide are used with chemical vapor deposition processes (PECVD, thermal CVD, SACVD, HDP CVD, and PE and Thermal ALD) to create hydrogen-free dielectric films. In some embodiments, there are multilayer dielectric films with sublayers of various materials such as silicon oxide, silicon nitride, and silicon oxynitride. In embodiments, the hydrogen-free reactants may include Tetra Isocyanato Silane, along with a hydrogen-free gas including, but not limited to, N2, O2, O3, N2O, CO2, CO and a combination thereof of these H-Free gases. Plasma may be used to enhance the reaction between the TICS and the other H-free gasses. The plasma may be controlled during film deposition to achieve variable density within each sublayer of the films.