Film forming method

A film forming method of forming a film containing a metal element on a substrate using a source gas containing the metal element and a reactant gas that reacts with the source gas, the method comprising:

• forming a lower layer film containing the metal element on a surface of the substrate through a chemical vapor deposition process (plasma CVD process) by supplying the source gas and the reactant gas into a process container and plasmarizing a mixture gas of the source gas and the reactant gas, the substrate on which a film is to be formed being disposed inside the process container;
• and
• subsequently, laminating an upper layer film containing the metal element on the lower layer film by an atomic layer deposition process (plasma ALD process) which alternately performs an adsorption step of supplying the source gas into the process container to adsorb the source gas onto the surface of the substrate with the lower layer film formed thereon, and a reaction step of supplying the reactant gas into the process container and plasmarizing the reactant gas so that the plasmarized reactant gas reacts with the source gas adsorbed onto the surface of the substrate.