Films of silicon oxide, nitride, and oxynitride produced by direct plasma enhanced chemical vapor deposition (DPECVD) and utilizing silane as one of the gas phase reactants generally contain up to ten times more bonded hydrogen than films produced by remote PECVD (RPECVD) and deposited at the same substrate temperature (Ts). We attribute this difference to the way silane is utilized in the deposition process chemistry. In DPECVD, silane is plasma excited along with other reactant gases, resulting in the formation of radicals and molecular fragments, e.g., SiH3 and SiH2, which at low temperatures (200–400 °C) serve as precursors for hydrogen incorporation, and in addition promote significant departures from insulator stoichiometry: SiO2−x, Si3N4−x, etc. In contrast, in the RPECVD process active oxygen and nitrogen species (and generally rare-gas diluents) are extracted from a remote plasma region and reacted with neutral silane to form precursor species with Si–O and Si–N bonding groups. These precursor molecules take part in chemical vapor deposition reactions in which hydrogen from SiH3 groups of the precursors is eliminated from the films through replacement reactions with excess active oxygen and nitrogen species.