Plasma processing apparatus and microwave introduction device

A plasma processing apparatus comprising:

• a process chamber for accommodating an object to be processed, a plane shape of the object being circular;
• a mounting table placed within the process chamber, the mounting table having a mounting surface for mounting the object thereon;
• a gas supply mechanism for supplying a process gas into the process chamber;
• and
• a microwave introduction device for introducing a microwave into the process chamber to produce a plasma of the process gas in the process chamber,
• wherein the microwave introduction device includes a conductive member, which is disposed above the process chamber and has a plurality of openings, and a plurality of microwave transmitting windows which is fitted into the respective openings and transmits and introduces the microwave into the process chamber,
• wherein the microwave transmitting windows are arranged on one virtual plane parallel to or substantially parallel to the mounting surface, the microwave transmitting windows including a first, a second and a third microwave transmitting window, the first to the third microwave transmitting window being disposed adjacent to each other, and
• wherein the first to the third microwave transmitting window are arranged such that a distances between center points of the first to the third microwave transmitting window are equal to or substantially equal to each other, and the center points of the first to the third microwave transmitting window are arranged with an equal or approximately equal interval on a circumference of a concentric circle to the plane shape of the object.