Film forming ring and method of manufacturing semiconductor device

A method of manufacturing a semiconductor device comprising:

• arranging a semiconductor substrate on which a film forming process by using a material gas in a plasma state is applied on a substrate supporter provided in a processing container, and mounting a film forming ring so as to be set an inner rim of a ring main body of the film forming ring being along an edge of the semiconductor substrate and an upper surface of the inner rim being positioned at a height equal to or lower than a principal plane of a side of the semiconductor substrate on which the film forming process is applied;
• supplying the material gas for use in the film forming process into the processing container;
• and
• generating the plasma state of the material gas in the processing container by applying a voltage to the material gas supplied in the processing container;
• wherein the ring main body is made of an insulating material and formed in an annular shape along the edge of the semiconductor substrate, and the inner rim is formed higher than its outside portion.