A chemical vapor deposition method for producing a dielectric film, the method comprising: providing a substrate into a reaction chamber; introducing gaseous reagents into the reaction chamber wherein the gaseous reagents comprise a silicon precursor comprising an silicon compound having Formula I as defined herein and applying energy to the gaseous reagents in the reaction chamber to induce reaction of the gaseous reagents to deposit a film on the substrate. The film as deposited is suitable for its intended use without an optional additional cure step applied to the as-deposited film.