Apparatus for adjusting an edge ring potential during substrate processing

Abstract

An apparatus for performing ion incident angle control while processing a substrate within a processing chamber is provided. The apparatus includes an edge ring surrounding the substrate disposed on a lower electrode, wherein the edge ring is electrically isolated from the lower electrode. The edge ring receives a first voltage from an edge ring direct current (DC) voltage control arrangement, resulting in an edge ring potential. The apparatus also includes a radio frequency source that provides power to the lower electrode and a gas distribution system that delivers gases into the processing chamber to interact with power to generate plasma to process the substrate. During processing, the edge ring DC voltage control arrangement is adjusted to cause the edge ring potential to be higher than the DC potential on the substrate, thereby causing the plasma to have a non-uniform angular ion distribution profile for processing the substrate edge.

1 - 30 . (canceled) 
     
     
         31 . An apparatus for performing ion incident angle control while processing a substrate within a plasma processing system, comprising:
 a processing chamber;   a lower electrode, wherein said substrate is disposed above said lower electrode during said processing of said substrate;   an edge ring, wherein said substrate is surrounded by said edge ring, wherein said edge ring is electrically isolated from said lower electrode;   an edge ring direct current (DC) voltage control arrangement, wherein said edge ring DC voltage control arrangement is coupled to said edge ring to provide a first voltage to said edge ring, resulting in said edge ring having an edge ring potential;   a radio frequency (RF) source, wherein said RF source is configured at least for providing power to said lower electrode; and   a gas distribution system, wherein said gas distribution system is configured at least for delivering a set of gases into said processing chamber, wherein said set of gases interact with said power delivered by said RF source to generate a plasma within said plasma processing chamber to process said substrate, said substrate being processed while said edge ring DC voltage control arrangement is configured to be adjusted to cause said plasma to have a non-uniform angular ion distribution profile for processing an edge of said substrate, wherein adjusting said edge ring DC voltage control arrangement causes said edge ring potential to be higher than a DC potential of said substrate.   
     
     
         32 . The apparatus of  claim 31  wherein said edge ring DC voltage control arrangement includes an RF filter arrangement and a DC power source, said RF filter arrangement being disposed between said edge ring and said DC power source. 
     
     
         33 . The apparatus of  claim 32  wherein said RF filter arrangement is configured to attenuate unwanted harmonic RF energy from reaching said DC power source. 
     
     
         34 . The apparatus of  claim 31  wherein said RF power has an RF frequency in a range from about 50 KHz to about 800 KHz. 
     
     
         35 . The apparatus of  claim 31  wherein said RF power has a set of RF frequencies that includes at least one of 2 MHz, 27 MHz, and 60 MHz. 
     
     
         36 . The apparatus of  claim 31  wherein said plasma processing chamber represents one of a capacitively-coupled plasma processing chamber and an inductively-coupled plasma processing chamber. 
     
     
         37 . The apparatus of  claim 31  wherein said edge ring DC voltage control arrangement includes one of an RF power supply and a DC power supply. 
     
     
         38 . The apparatus of  claim 31  further including a feedback circuit configured to monitor said DC potential of said substrate, whereby said DC potential of said substrate is employed as a feedback signal to vary said first voltage when said DC potential of said substrate changes. 
     
     
         39 . An apparatus for reducing polymer deposition around an edge of a substrate during processing within a plasma processing system, comprising:
 a processing chamber;   a lower electrode, wherein said substrate is disposed above said lower electrode during said processing of said substrate;   an edge ring, wherein said substrate is surrounded by said edge ring, wherein said edge ring is electrically isolated from said lower electrode;   an edge ring direct current (DC) voltage control arrangement, wherein said edge ring DC voltage control arrangement is coupled to said edge ring to provide a first voltage to said edge ring, resulting in said edge ring having an edge ring potential;   a radio frequency (RF) source, wherein said RF source is configured at least for providing power to said lower electrode; and   a gas distribution system, wherein said gas distribution system is configured at least for delivering a set of gases into said processing chamber, wherein said set of gases interact with said power delivered by said RF source to generate a plasma within said plasma processing chamber to process said substrate, said substrate being processed while said edge ring DC voltage control arrangement is configured to be adjusted to cause said edge ring potential to be different from a DC potential of said substrate while processing said substrate so as to cause an ion incident angle of ions disposed in a vicinity of said edge of said substrate to be biased toward said edge of said substrate and away from said edge ring, wherein adjusting said edge ring DC voltage control arrangement causes said plasma to have a non-uniform angular ion distribution profile.   
     
     
         40 . The apparatus of  claim 39  wherein said edge ring DC voltage control arrangement includes an RF filter arrangement and a DC power source, said RF filter arrangement being disposed between said edge ring and said DC power source. 
     
     
         41 . The apparatus of  claim 40  wherein said RF filter arrangement is configured to attenuate unwanted harmonic RF energy. 
     
     
         42 . The apparatus of  claim 39  wherein said plasma processing chamber represents one of capacitively-coupled plasma processing chamber and an inductively coupled plasma processing chamber. 
     
     
         43 . The apparatus of  claim 39  wherein said RF power has an RF frequency in a range from about 50 KHz to about 800 KHz. 
     
     
         44 . The apparatus of  claim 39  wherein said RF power has a set of RF frequencies that includes at least one of 2 MHz, 27 MHz, and 60 MHz. 
     
     
         45 . The apparatus of  claim 39  wherein said edge ring DC voltage control arrangement includes one of an RF power supply and a DC power supply. 
     
     
         46 . The apparatus of  claim 39  further including a feedback circuit configured to monitor said DC potential of said substrate, whereby said DC potential of said substrate is employed as a feedback signal to vary said first voltage when said DC potential of said substrate changes. 
     
     
         47 . An apparatus for performing ion incident angle control while processing a substrate within a plasma processing system, comprising:
 a processing chamber;   a lower electrode, wherein said substrate is disposed above said lower electrode during said processing of said substrate;   an edge ring, wherein said substrate is surrounded by said edge ring, wherein said edge ring is electrically isolated from said lower electrode;   an edge ring direct current (DC) voltage control arrangement, wherein said edge ring DC voltage control arrangement is coupled to said edge ring to provide a first voltage to said edge ring, resulting in said edge ring having an edge ring potential;   a radio frequency (RF) source, wherein said RF source is configured at least for providing power to said lower electrode; and   a gas distribution system, wherein said gas distribution system is configured at least for delivering a set of gases into said processing chamber, wherein said set of gases interact with said power delivered by said RF source to generate a plasma within said plasma processing chamber to process said substrate, said substrate being processed while said edge ring DC voltage control arrangement is configured to be adjusted to cause said plasma to have a non-uniform angular ion distribution profile for processing an edge of said substrate, wherein adjusting said edge ring DC voltage control arrangement causes said edge ring potential to be less than a DC potential of said substrate.   
     
     
         48 . The apparatus of  claim 47  wherein said edge ring DC voltage control arrangement includes an RF filter arrangement and a DC power source, said RF filter arrangement being disposed between said edge ring and said DC power source. 
     
     
         49 . The apparatus of  claim 48  wherein said RF filter arrangement is configured to attenuate unwanted harmonic RF energy. 
     
     
         50 . The apparatus of  claim 47  further including a feedback circuit configured to monitor said DC potential of said substrate, whereby said DC potential of said substrate is employed as a feedback signal to vary said first voltage when said DC potential of said substrate changes.