This invention relates to materials and processes for thin film deposition on solid substrates. Silica/alumina nanolaminates were deposited on heated substrates by the reaction of an aluminum-containing compound with a silanol. The nanolaminates have very uniform thickness and excellent step coverage in holes with aspect ratios over 40:1. The films are transparent and good electrical insulators. This invention also relates to materials and processes for producing improved porous dielectric materials used in the insulation of electrical conductors in microelectronic devices, particularly through materials and processes for producing semi-porous dielectric materials wherein surface porosity is significantly reduced or removed while internal porosity is preserved to maintain a desired low-k value for the overall dielectric material. The invention can also be used to selectively fill narrow trenches with low-k dielectric material while at the same time avoiding deposition of any dielectric on the surface area outside of the trenches.