FILM FORMATION METHOD

Provided is a film formation method whereby nonuniformity of film quality in the X-axis direction of a substrate can be suppressed when an indium oxide-based oxide film is formed on the surface of thesubstrate. This film formation method comprises forming an indium-oxide-based oxide film on the surface of a substrate Sw by setting mutually orthogonal directions in the plane of the substrate as the X-axis direction and the Y-axis direction, placing the substrate and targets Tg1 through Tg8 having a greater length in the X-axis direction than the substrate in a vacuum treatment chamber 11 so asto face each other concentrically, introducing a noble gas and oxygen gas to the vacuum treatment chamber in a vacuum atmosphere, and supplying electric power to the targets and sputtering the targets with ions of the noble gas in a plasma atmosphere. The direction from the target side to the substrate being the upward direction, oxygen gas is introduced toward the substrate from a first positiondirectly below a substrate