Plasma processor

Abstract

An electromagnetic field generating coil included in plasma processing apparatus is realized with a balanced transmission line. Conductors constituting the balanced transmission line are disposed vertically above a wafer. A uniform electromagnetic field is generated in parallel with the wafer using the balanced transmission line. A gas inlet is formed above the balanced transmission line so that a gas will flow into the wafer after passing through the electromagnetic field generated around the balanced transmission line. The balanced transmission line may be formed spirally.

1 . Plasma processing apparatus that produces gas plasma in a vacuum chamber by generating an electromagnetic field so as to treat an object by the plasma, comprising a balanced transmission line that is connected to a high-frequency power supply and that has a terminal thereof used to attain an impedance match, wherein; 
 two conductors constituting said balanced transmission line are disposed vertically.    
   
   
       2 . Plasma processing apparatus according to  claim 1 , wherein said balanced transmission line is disposed within said vacuum chamber.  
   
   
       3 . Plasma processing apparatus according to  claim 2 , wherein a gas inlet is formed above said balanced transmission line.  
   
   
       4 . Plasma processing apparatus according to  claim 2 , wherein said balanced transmission line is formed as a heater.  
   
   
       5 . Plasma processing apparatus according to  claim 4 , wherein a high-frequency current fed from said high-frequency power supply and a heater direct current are superposed on each other on said balanced transmission line.  
   
   
       6 . Plasma processing apparatus according to  claim 1 , wherein said balanced transmission line is disposed outside said vacuum chamber.  
   
   
       7 . Plasma processing apparatus according to  claim 1 , wherein one of said conductors constituting said balanced transmission line is disposed outside said vacuum chamber, and the other conductor is disposed within said vacuum chamber.  
   
   
       8 . Plasma processing apparatus according to  claim 7 , therein said balanced transmission line comprises two conductors embedded in the top and bottom of a dielectric, and a gas passageway and a gas outlet are formed in said dielectric plate.  
   
   
       9 . Plasma processing apparatus according to  claim 7 , wherein said balanced transmission line comprises two dielectric plates each having a conductor, the space between said two dielectric plates is used as a gas passageway, and a gas outlet is formed in the lower dielectric plate.  
   
   
       10 . Plasma processing apparatus according to  claim 1 , wherein said balanced transmission line is curved.  
   
   
       11 . Plasma processing apparatus according to  claim 10 , wherein said balanced transmission line is formed spirally.  
   
   
       12 . Plasma processing apparatus according to  claim 10 , wherein said balanced transmission line is formed tortuously.  
   
   
       13 . Plasma processing apparatus according to  claim 10 , wherein the spacing between adjoining portions of said balanced transmission line is not equal.  
   
   
       14 . Plasma processing apparatus according to  claim 1 , wherein said balanced transmission line is connected to said high-frequency power supply over a coaxial cable via a balun.  
   
   
       15 . Plasma processing apparatus according to  claim 1 , wherein said object is a semiconductor wafer.  
   
   
       16 . Plasma processing apparatus that produces the gas plasma in a vacuum chamber by generating an electromagnetic field so as to treat an object by the plasma, comprising a microstrip line that is connected to a high-frequency power supply and that has a terminal thereof used to attain an impedance match, wherein; 
 said microstrip line comprises at least a grounded plane and a conducting strip disposed within said vacuum chamber; and    a gas introduction path is formed between said ground plane and said conducting strip.    
   
   
       17 . Plasma processing apparatus according to  claim 16 , wherein a dielectric is interposed between said grounded plane and said conducting strip, and a gas passageway and a gas outlet are formed in said dielectric plate.  
   
   
       18 . Plasma processing apparatus according to  claim 16 , wherein said conducting strip is formed spirally.  
   
   
       19 . Plasma processing apparatus according to  claim 16 , wherein said conducting strip is formed tortuously.  
   
   
       20 . Plasma processing apparatus according to  claim 16 , wherein the spacing between adjoining portions of said conducting strip is not equal.  
   
   
       21 . Plasma processing apparatus according to  claim 16 , wherein said object is a semiconductor wafer.