Methods of processing films on substrates are provided. In one aspect, the methods comprise treating a patterned low dielectric constant film after a photoresist is removed from the film by depositing a thin layer comprising silicon, carbon, and optionally oxygen and/or nitrogen on the film. The thin layer provides a carbon-rich, hydrophobic surface for the patterned low dielectric constant film. The thin layer also protects the low dielectric constant film from subsequent wet cleaning processes and penetration by precursors for layers that are subsequently deposited on the low dielectric constant film.