Film deposition apparatus

A film deposition apparatus for depositing a thin film on a substrate by carrying out a cycle of alternately supplying at least two kinds of reaction gases that react with each other to the substrate to produce a layer of a reaction product in a vacuum chamber, the film deposition apparatus comprising:

• a turntable rotatably provided in the vacuum chamber;
• a substrate receiving portion that is provided in the turntable in order to place the substrate therein;
• a first reaction gas supplying portion and a second reaction gas supplying portion that are separated from each other along a rotation direction of the turntable, and supply a first reaction gas and a second reaction gas, respectively, to a surface of the turntable, the surface being on the substrate receiving portion side;
• a separation area located along the rotation direction between a first process area in which the first reaction gas is supplied and a second process area in which the second reaction gas is supplied,
• a center area that is located substantially in a center portion of the vacuum chamber in order to separate atmospheres of the first process area and the second process area, and in which an ejection hole is formed that ejects a separation gas to the surface of the turntable, the surface being on the substrate receiving portion side;
• and
• an evacuation opening provided in the vacuum chamber in order to evacuate the vacuum chamber,
• wherein the separation area includes
• a lower surface that is lower than a ceiling surface of each of the first and the second process areas in relation to the turntable and has a width becoming substantially greater toward a circumference of the vacuum chamber, the width being along the rotation direction, thereby to create in relation to the turntable a thin space, and
• a separation gas supplying portion that is positioned within the lower surface and supplies a separation gas to the thin space thereby to create separation gas flows from the separation area to the process area sides in relation to the rotation direction.