1. A method of forming a silica-containing ceramic coating on a substrate comprising: applying a coating comprising a silicon hydride resin of the structure (SiO.sub.2).sub.x (RSiO.sub.3/2).sub.y (R.sub.2 SiO).sub.z on the substrate, wherein R independently comprises hydrogen or a hydrocarbon of 1 to 20 carbon atoms, y is a mole fraction between about 0.05 and 1, and x and z are mole fractions between about 0 and about 0.95, with the proviso that at least about 20% of the R groups are hydrogen; and heating the coated substrate in an atmosphere comprising nitrous oxide at a temperature sufficient to convert the silicon hydride resin coating to a silica-containing ceramic coating.