NITRIDE FILM FORMING METHOD

There is provided a method of forming a nitride film, including: repeating a cycle including an adsorption process of adsorbing a film forming precursor gas onto a substrate having a surface in which a fine recess is formed, the film forming precursor gas containing an element and chlorine constituting a nitride film to be formed; and a nitriding process of nitriding the adsorbed film forming precursor gas with nitriding active species, to form the nitride film in the fine recess. The nitriding process includes: generating NH* active species and N* active species as a nitriding active species; and controlling concentrations of the NH* active species and the N* active species to vary an area where the film forming precursor gas is adsorbed in the fine recess.