Plasma processing apparatus and microwave introduction device

Abstract

A plasma processing apparatus includes a microwave introduction device which introduces a microwave into a process chamber. The microwave introduction device includes a plurality of microwave transmitting plates which is fitted into a plurality of openings of a ceiling. The microwave transmitting plates are arranged on one virtual plane parallel to a mounting surface of a mounting table, with the microwave transmitting plates fitted into the respective openings. The microwave transmitting plates includes first to third microwave transmitting plates. The first to third microwave transmitting plates are arranged in such a manner that a distance between the center point of the first microwave transmitting window and the center point of the second microwave transmitting window becomes equal or approximately equal to a distance between the center point of the first microwave transmitting window and the center point of the third microwave transmitting window.

1 . 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.   
     
     
         2 . The plasma processing apparatus of  claim 1 ,
 wherein density distributions of a plurality of microwave plasmas produced by microwaves introduced from the microwave transmitting windows into the process chamber are equal to or substantially equal to each other, and   wherein, assuming that a diameter of the plane shape of the object is 1 and a distance between the center points of any two adjacent microwave transmitting windows is Lp, a full width at half maximum of the density distributions of the microwave plasmas is equal to or larger than 0.47×Lp+0.56 and is equal to or larger than −19×Lp+21.   
     
     
         3 . The plasma processing apparatus of  claim 1 , wherein outer edges of a virtual triangle formed by interconnecting the center points of the first to the third microwave transmitting window include a figure formed by projecting the plane shape of the object onto the virtual plane. 
     
     
         4 . The plasma processing apparatus of  claim 1 , wherein the microwave introduction device includes a microwave output unit which generates microwaves and distributes the microwaves into a plurality of paths, and a plurality of microwave introduction modules, each including one microwave transmitting window, which introduces the microwaves output from the microwave output unit into the process chamber, and
 wherein the microwave introduction modules have the same configuration.   
     
     
         5 . A microwave introduction device for introducing a microwave into a process chamber for accommodating an object to produce a plasma of a process gas in the process chamber, a plane shape of the object being circular, comprising:
 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, 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 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.   
     
     
         6 . The microwave introduction device of  claim 5 ,
 wherein density distributions of a plurality of microwave plasmas produced by microwaves introduced from the microwave transmitting windows into the process chamber are equal to or substantially equal to each other, and   wherein, assuming that a diameter of the plane shape of the object is 1 and a distance between the center points of any two adjacent microwave transmitting windows is Lp, a full width at half maximum of the density distributions of the microwave plasmas is equal to or larger than 0.47×Lp+0.56 and is equal to or larger than −19×Lp+21.   
     
     
         7 . The microwave introduction device of  claim 5 , wherein outer edges of a virtual triangle formed by interconnecting the center points of the first to the third microwave transmitting window include a figure formed by projecting the plane shape of the object onto the virtual plane. 
     
     
         8 . The microwave introduction device of  claim 5 , further comprising:
 a microwave output unit which generates microwaves and distributes the microwaves into a plurality of paths; and   a plurality of microwave introduction modules, each including one microwave transmitting window, which introduces the microwaves output from the microwave output unit into the process chamber,   wherein the microwave introduction modules have the same configuration.