Plasma processing apparatus and plasma processing method

Abstract

A plasma processing apparatus includes a processing chamber which has a dielectric wall partly formed of a dielectric substance and in which a to-be-processed substrate is subjected to a plasma process, an induction coil which is arranged to face the dielectric wall and generates an induction electric field to generate plasma in the processing chamber, a Faraday shield which is provided to partially have openings between the dielectric wall and the induction coil to shield an electrostatic field component and pass an electromagnetic field component, and a drive mechanism which moves the Faraday shield.

1 . A plasma processing apparatus comprising:
 a processing chamber which has a dielectric wall partly formed of a dielectric substance and in which a to-be-processed substrate is subjected to a plasma process,   an induction coil which is arranged to face the dielectric wall and generates an induction electric field to generate plasma in the processing chamber,   a Faraday shield which is provided to partially have openings between the dielectric wall and the induction coil to shield an electrostatic field component and pass an electromagnetic field component, and   a drive mechanism which moves the Faraday shield.   
   
   
       2 . The plasma processing apparatus according to  claim 1 , wherein the dielectric wall is cylindrical, the Faraday shield is arranged to cover an outer peripheral surface of the dielectric wall and the openings of the Faraday shield are arranged in a circumferential direction of the dielectric wall at regular intervals. 
   
   
       3 . The plasma processing apparatus according to  claim 2 , wherein the Faraday shield is configured by arranging strip-form metal plates in an outer peripheral direction of the dielectric wall at regular intervals. 
   
   
       4 . The plasma processing apparatus according to  claim 2 , wherein the drive mechanism causes the Faraday shield to make one of a rotational movement and a reciprocal rotational movement along the outer peripheral surface of the dielectric wall. 
   
   
       5 . The plasma processing apparatus according to  claim 1 , wherein the Faraday shield includes a plurality of Faraday shields coaxially overlapped in plural stages and each stage is provided to be independently moved. 
   
   
       6 . The plasma processing apparatus according to  claim 4 , wherein a total numerical aperture of the Faraday shield is controlled by changing an overlapping state of the Faraday shields of the plural stages. 
   
   
       7 . The plasma processing apparatus according to  claim 1 , wherein a lower portion of the processing chamber is formed of metal and an upper portion thereof is formed of the dielectric substance. 
   
   
       8 . The plasma processing apparatus according to  claim 1 , wherein the processing chamber is formed to be cylindrical. 
   
   
       9 . The plasma processing apparatus according to  claim 1 , wherein a gas inlet port which introduces gas used for a plasma process is provided in an upper portion of the processing chamber and a gas outlet port which discharges the gas is provided in a lower portion thereof. 
   
   
       10 . The plasma processing apparatus according to  claim 1 , wherein a dielectric substance forming the dielectric wall is quartz. 
   
   
       11 . The plasma processing apparatus according to  claim 1 , wherein the dielectric wall is formed in a cylindrical form to cover an upper surface of the processing chamber, the Faraday shield is arranged above the dielectric wall and the Faraday shield has shielding portions and opening portions alternately arranged in a circumferential direction. 
   
   
       12 . The plasma processing apparatus according to  claim 11 , wherein the processing chamber is formed in a cylindrical form and the dielectric wall is provided to cover an opening of an upper-side portion of the processing chamber. 
   
   
       13 . The plasma processing apparatus according to  claim 11 , wherein the Faraday shield is obtained by radially arranging fan-shaped metal plates used as the shielding portions at regular intervals. 
   
   
       14 . The plasma processing apparatus according to  claim 11 , wherein the drive mechanism causes the Faraday shield to move coaxially with the rotation of the dielectric wall. 
   
   
       15 . A plasma processing method comprising:
 preparing a plasma processing apparatus having a dielectric wall formed of a dielectric substance and partly disposed in a processing chamber used for a plasma process and a Faraday shield which is provided to partially have openings between the dielectric wall and an induction coil to shield an electrostatic field component and pass an electromagnetic field component,   generating plasma in the processing chamber by supplying gas into the processing chamber and generating an induction electric field in the processing chamber by use of the induction coil, and   changing a positional relation of the openings of the Faraday shield with respect to the dielectric wall by moving the Faraday shield during the plasma process by use of the plasma or moving the Faraday shield after elapse of a preset processing period of time.