Processes are provided herein for deposition of organic films. Organic films can be deposited, including selective deposition on one surface of a substrate relative to a second surface of the substrate. For example, polymer films may be selectively deposited on a first metallic surface relative to a second dielectric surface. Selectivity, as measured by relative thicknesses on the different layers, of above about 50% or even about 90% is achieved. The selectively deposited organic film may be subjected to an etch process to render the process completely selective. Processes are also provided for particular organic film materials, independent of selectivity. Masking applications employing selective organic films are provided. Post-deposition modification of the organic films, such as metallic infiltration and/or carbon removal, is also disclosed.