Plasma processing apparatus

Abstract

A plasma processing apparatus includes: a first electrode including a hollow penetrated through from an upper end thereof to a lower end thereof; a workpiece stage to place a workpiece; a second electrode arranged opposing to a lower end of the first electrode through the workpiece stage; a processing gas nozzle formed on an outer circumference side of an opening at the lower end of the hollow along a circumferential direction; a power source circuit including a power source applying a voltage between the first electrode and the second electrode; and a gas supply system supplying a processing gas to generate plasma to the processing gas nozzle. The plasma is generated by activating the processing gas that is ejected out of the processing gas nozzle and located around immediately below the opening at the lower end upon voltage application between the first electrode and the second electrode so as to process a surface of the workpiece by the plasma.

1 . A plasma processing apparatus, comprising:
 a first electrode including a hollow penetrated through from an upper end thereof to a lower end thereof;   a workpiece stage to place a workpiece;   a second electrode arranged opposing to a lower end of the first electrode through the workpiece stage;   a processing gas nozzle formed on an outer circumference side of an opening at the lower end of the hollow along a circumferential direction;   a power source circuit including a power source applying a voltage between the first electrode and the second electrode; and   a gas supply system supplying a processing gas to generate plasma to the processing gas nozzle, wherein the plasma is generated by activating the processing gas that is ejected out of the processing gas nozzle and located around immediately below the opening at the lower end upon voltage application between the first electrode and the second electrode so as to process a surface of the workpiece by the plasma.   
   
   
       2 . The plasma processing apparatus according to  claim 1 , wherein the processing gas ejected from the processing gas nozzle flows in a direction toward the opening at the lower end and in a direction apart from the opening at the lower end. 
   
   
       3 . The plasma processing apparatus according to  claim 1 , wherein a flow of the processing gas from the opening at the lower end toward the upper end of the hollow is formed in the hollow. 
   
   
       4 . The plasma processing apparatus according to  claim 1 , wherein the processing gas nozzle is intermittently formed on the outer circumference side of the opening along the circumferential direction. 
   
   
       5 . The plasma processing apparatus according to  claim 1 , wherein the processing gas nozzle is formed in an annular shape around a whole circumference of the opening at the lower end. 
   
   
       6 . The plasma processing apparatus according to  claim 1 , wherein the processing gas nozzle ejects the processing gas in a direction inclined toward an extended line of a line connecting the upper end and the lower end of the hollow. 
   
   
       7 . The plasma processing apparatus according to  claim 1 , further comprising a gas exhaust system exhausting the processing gas ejected from the processing gas nozzle from the upper end of the hollow of the first electrode. 
   
   
       8 . The plasma processing apparatus according to  claim 7 , wherein the gas exhaust system includes an outlet flow adjustment unit adjusting an amount of an outlet flow of the processing gas exhausted from the upper end of the hollow. 
   
   
       9 . The plasma processing apparatus according to  claim 8 , wherein the outlet flow adjustment unit includes:
 an outlet duct connected with the upper end of the hollow;   a valve opening and shutting a flow passage in the outlet duct; and   a pump formed on a downstream side of the outlet duct through the valve.   
   
   
       10 . The plasma processing apparatus according to  claim 1 , further comprising a cooling system to cool off the first electrode. 
   
   
       11 . The plasma processing apparatus according to  claim 1 , wherein the first electrode has a surface facing to the second electrode, at least the surface being covered with a dielectric portion. 
   
   
       12 . The plasma processing apparatus according to  claim 11 , wherein the processing gas nozzle is formed on the dielectric portion. 
   
   
       13 . The plasma processing apparatus according to  claim 11 , wherein the dielectric portion has an external diameter expanded more than an external diameter of the first electrode. 
   
   
       14 . The plasma processing apparatus according to  claim 1 , wherein the first electrode is provided in a plurality of numbers.