Method for plasma processing by shaping an induced electric field

Abstract

A method for achieving a highly uniform plasma density on a substrate by shaping an induced electric field including the steps of positioning the substrate in a processing chamber, supplying a high frequency power to a spiral antenna generating an induced electric field in the processing chamber, generating a plasma in the processing chamber, and shaping the electric field with respect to the substrate to achieve a uniform distribution of plasma on the substrate being processed.

1. A method for processing a substrate with plasma, comprising the steps of:
 positioning the substrate in a processing chamber;  
 supplying a high frequency power to a substantially planar spiral antenna from a central area thereof and generating an induced electric field in the processing chamber;  
 generating a plasma in said processing chamber; and  
 shaping said induced electric field with respect to said substrate so as to achieve a uniform distribution of said plasma on said substrate.  
 
     
     
       2. The method according to  claim 1 , wherein:
 said supplying step includes supplying the high frequency power to the spiral antenna and impedance matching an output of a high frequency power supply to an input of said spiral antenna.  
 
     
     
       3. The method according to  claim 1 , further comprising a step of controlling a supply of the high frequency power by a controller. 
     
     
       4. The method according to  claim 1 , wherein:
 said supplying step comprises, 
 generating an alternating magnetic field having flux lines that pass through a dielectric member disposed between said spiral antenna and said substrate in said processing chamber.  
 
 
     
     
       5. The method according to  claim 1 , wherein:
 said supplying step comprises, 
 supplying the high frequency power to said spiral antenna which includes a plurality of curved antenna segments having inner ends which are positioned at the central area.  
 
 
     
     
       6. The method according to  claim 5 , wherein:
 said supplying step comprises, 
 supplying the high frequency power to said curved antenna segments, each of said curved antenna segments spiralling radially outward in a same direction, said direction being either clockwise or counterclockwise.  
 
 
     
     
       7. The method according to  claim 1  wherein:
 said shaping step includes, 
 disposing a paramagnetic plate under said spiral antenna.  
 
 
     
     
       8. The method according to  claim 1 , wherein the substantially planar spiral coil is a continuous coil. 
     
     
       9. The method according to  claim 1 , wherein the substantially planar spiral coil comprises at least two elongated members that are separated in a radial direction. 
     
     
       10. A method for processing a substrate by a plasma processing apparatus including a processing chamber, a susceptor having a supporting area for supporting the substrate in the processing chamber, a spiral antenna having at least two elongated members, each of the members having an inner end and an outer end and outwardly extending from a central area of the processing chamber, and a dielectric member positioned between the supporting area of the susceptor and the spiral antenna, the method comprising:
   supporting the substrate in the supporting area of the susceptor;        introducing a processing gas into the processing chamber;        supplying a high frequency power to one of the inner and the outer end of each of the elongated members to generate an induced electric field in the processing chamber; and        generating a plasma in the processing chamber;      
       
         wherein each of the at least two elongated members is a separate member separately supplied with high frequency power. 
       
     
     
       11. The method according to  claim 8 , wherein said supplying comprises:
   supplying the high frequency power to the inner end of each of the elongated members.     
     
     
       12. The method according to  claim 10 , wherein said supplying comprises:
   supplying the high frequency power to one of the inner end and the outer end of each of the elongated members through a matching circuit.     
     
     
       13. The method according to  claim 10 , wherein turns of the spiral antenna are arranged so that a pitch of the turns in a central region is greater than a pitch in an outer region. 
     
     
       14. A method for processing a substrate by a plasma processing apparatus, comprising
   positioning the substrate in a processing chamber;        applying a high frequency power to inner end portions of a plurality of elongated members of a spiral antenna, the inner end portions of the elongated members being positioned in a central area of the spiral antenna, and the elongated members be in outwardly extended from the central area in a curved shape to generate an induced electric field in the processing chamber; and        generating a plasma in the processing chamber to process the substrate;      
       
         wherein each of the plurality of elongated members is a separate member separately supplied with high frequency power. 
       
     
     
       15. The method according to  claim 14 , wherein said applying the high frequency power comprises:
   supplying high frequency power to the inner end of each of the elongated members through a matching circuit.     
     
     
       16. The method according to  claim 14 , wherein turns of the spiral antenna are arranged so that a pitch of the turns in a central region is greater than a pitch in an outer region. 
     
     
       17. The method according to  claim 14 , wherein each of the elongated members of the spiral antenna is extended along a surface of the processing chamber. 
     
     
       18. The method according to  claim 17 , wherein each of the elongated members comprises a flat elongated surface that is in contact with the surface of the processing chamber.