Patent ID: 8647722

Claim:
A method of forming a film for forming a layer of insulation film composed of multiple sub-layers of film on a substrate, comprising: (i) forming one or more sub-layers on the substrate by a film-forming cycle of plasma ALD or pulse plasma CVD using a precursor, each film-forming cycle using a plasma for forming a sub-layer of the same layer of insulation film; (ii) treating a surface of the one or more sub-layers on the substrate by a reforming cycle which is not included in the film-forming cycle, said reforming cycle using a plasma without using the precursor, for treating the surface of the one or more sub-layers, which plasma is selected from the group consisting of hydrogen plasma, ammonia plasma, oxygen plasma, nitrous oxide plasma, carbon dioxide plasma, argon plasma, and xenon plasma, except nitrogen plasma; and (iii) repeating steps (i) and (ii) until the layer of insulation film composed of multiple sub-layers is formed, wherein a purge cycle without RF power is provided between step (i) and (ii).