Provided are methods and apparatuses for depositing a graded or multi-layered silicon carbide film using remote plasma. A graded or multi-layered silicon carbide film can be formed under process conditions that provide one or more organosilicon precursors onto a substrate in a reaction chamber. Radicals of source gas in a substantially low energy state, such as radicals of hydrogen in the ground state, are provided from a remote plasma source into reaction chamber. In addition, co-reactant gas is flowed towards the reaction chamber. In some implementations, radicals of the co-reactant gas are provided from the remote plasma source into the reaction chamber. A flow rate of the co-reactant gas can be changed over time, incrementally or gradually, to form a multi-layered silicon carbide film or a graded silicon carbide film having a composition gradient from a first surface to a second surface of the graded silicon carbide film.