Plasma processing system

Abstract

There is provided a plasma processing system capable of making a processing rate uniform without the occurrence of charge-up damage and arcing damage when a substrate to be processed is plasma-processed. The plasma processing system comprises: a chamber ( 1 ) capable of being held in vacuum; a pair of electrodes which face each other in the chamber, the pair of electrodes comprising a first electrode ( 2 ) for supporting thereon a substrate (W) to be processed, and a second electrode ( 16 ) facing the first electrode; electric field forming means ( 10 ) for forming a high-frequency field having a predetermined power density between the pair of electrodes; process gas supply means ( 15 ) for supplying a process gas into the chamber; magnetic field forming means ( 21 ), provided around the chamber, for forming a magnetic field around a processing space which is formed between the pair of electrodes; and a conductive or insulating focus ring ( 5 ) which is provided around the substrate on the first electrode, wherein the ratio of the outer diameter of the focus ring to the diameter of the substrate is set to be in the range of from about 1.3 to about 1.4.

What is claimed is:  
     
         1 . A plasma processing system comprising: 
 a chamber capable of being held in vacuum;    a pair of electrodes which face each other in said chamber, said pair of electrodes comprising a first electrode for supporting thereon a substrate to be processed, and a second electrode facing the first electrode;    electric field forming means for forming a high-frequency field having a predetermined power density between said pair of electrodes;    process gas supply means for supplying a process gas into said chamber;    magnetic field forming means, provided around said chamber, for forming a magnetic field around a processing space which is formed between said pair of electrodes; and    a conductive or insulating focus ring which is provided around said substrate on said first electrode, wherein the ratio of the outer diameter of said focus ring to the diameter of said substrate is set to be in the range of from about 1.3 to about 1.4.    
     
     
         2 . A plasma processing system as set forth in  claim 1 , wherein the outer diameter of said focus ring is set to be in the range of from 275 mm to 280 mm when the diameter of said substrate is 203 mm (8 inches) if the power density of said high-frequency field applied to said substrate is in the range of from 2.8 W/cm 2  to 3.9 W/cm 2 .  
     
     
         3 . A plasma processing system as set forth in  claim 2 , wherein the outer diameter of said focus ring is set to be greater than 275 mm and not greater than 280 mm when the diameter of said substrate is 203 mm (8 inches) if the power density of said high-frequency field applied to said substrate is in the range of from 2.8 W/cm 2  to 3.9 W/cm 2 .  
     
     
         4 . A plasma processing system as set forth in  claim 2 , wherein the outer diameter of said focus ring is set to be in the range of from 275 mm to 280 mm when the diameter of said substrate is 203 mm (8 inches) if the power density of said high-frequency field applied to said substrate is not less than 2.8 W/cm 2  and less than 3.9 W/cm 2 .  
     
     
         5 . A plasma processing system as set forth in  claim 1 , wherein the outer diameter of said focus ring is set to be in the range of from 412 mm to 420 mm when the diameter of said substrate is 305 mm (12 inches) if the power density of said high-frequency field applied to said substrate is in the range of from 2.8 W/cm 2  to 3.9 W/cm 2 .  
     
     
         6 . A plasma processing system as set forth in  claim 5 , wherein the outer diameter of said focus ring is set to be greater than 412 mm and not greater than 420 mm when the diameter of said substrate is 305 mm (12 inches) if the power density of said high-frequency field applied to said substrate is in the range of from 2.8 W/cm 2  to 3.9 W/cm 2 .  
     
     
         7 . A plasma processing system as set forth in  claim 5 , wherein the outer diameter of said focus ring is set to be in the range of from 412 mm to 420 mm when the diameter of said substrate is 305 mm (12 inches) if the power density of said high-frequency field applied to said substrate is not less than 2.8 W/cm 2  and less than 3.9 W/cm 2 .  
     
     
         8 . A plasma processing system as set forth in  claim 1 , wherein the outer diameter of said focus ring is set to be in the range of from 275 mm to 280 mm when the diameter of said substrate is 203 mm (8 inches), and in the range of from 412 mm to 420 mm when the diameter of said substrate is 305 mm (12 inches), if the power density of said high-frequency field applied to said substrate is 2.8 W/cm 2 .  
     
     
         9 . A plasma processing system as set forth in  claim 1 , wherein the outer diameter of said focus ring is set to be greater than 275 mm and not greater than 280 mm when the diameter of said substrate is 203 mm (8 inches), and is set to be greater than 412 mm and not greater than 420 mm when the diameter of said substrate is 305 mm (12 inches), if the power density of said high-frequency field applied to said substrate is 3.9 W/cm 2 .