According to the invention there is provided a method of filling one or more gaps created during manufacturing of a feature on a substrate by providing a deposition method comprising; introducing a first reactant to the substrate with a first dose, thereby forming no more than about one monolayer by the first reactant; introducing a second reactant to the substrate with a second dose. The first reactant is introduced with a sub saturating first dose reaching only a top area of the surface of the one or more gaps and the second reactant is introduced with a saturating second dose reaching a bottom area of the surface of the one or more gaps. A third reactant may be provided to the substrate in the reaction chamber with a third dose, the third reactant reacting with at least one of the first and second reactant.

A method of forming a surface treatment film on a substrate having, on a surface thereof, a first region where an insulator is exposed and a second region where at least one metallic matter is exposed, in which the surface treatment film is formed on the second region and is capable of suppressing intrusion of the surface treatment film onto the first region. A method of forming a surface treatment film, including preparing the substrate, oxidizing a surface of the second region, and forming a surface treatment film on the second region by exposing a surface of the substrate after the oxidation to a surface-treatment agent including a thiol having 8 or less carbon atoms.