Methods and apparatus for stripping

Abstract

One embodiment of the present invention is a stripping reactor that includes: (a) a remote plasma source disposed to output a gas; (b) a gas distribution plate connected to ground that transmits the gas output from the remote plasma source to a processing chamber; (c) a wafer support disposed in the processing chamber; (d) a wafer support assembly disposed about the wafer pedestal that includes an outer conductive peripheral structure connected to ground; and (e) an RF power supply connected to supply RF power to the wafer support.

1 . A stripping reactor that comprises: 
 a remote plasma source disposed to output a gas;    a gas distribution plate connected to ground that transmits the gas output from the remote plasma source to a processing chamber;    a wafer support disposed in the processing chamber;    a wafer support assembly disposed about the wafer support that includes an outer conductive peripheral structure connected to ground; and    an RF power supply connected to supply RF power to the wafer support.    
   
   
       2 . The stripping reactor of  claim 1  wherein the gas distribution plate is conductive.  
   
   
       3 . The stripping reactor of  claim 1  wherein the remote plasma source is an inductively coupled plasma source.  
   
   
       4 . The stripping reactor of  claim 1  wherein the remote plasma source is a microwave coupled plasma source.  
   
   
       5 . The stripping reactor of  claim 1  wherein the processing chamber comprises a grounded chamber body.  
   
   
       6 . The stripping reactor of  claim 1  wherein the wafer support assembly further comprises a non-conductive peripheral structure situated between the wafer support and the conductive peripheral structure.  
   
   
       7 . The stripping reactor of  claim 6  wherein the non-conductive peripheral structure comprises quartz.  
   
   
       8 . The stripping reactor of  claim 6  wherein the non-conductive peripheral structure includes a vertical lip.  
   
   
       9 . The stripping reactor of  claim 6  wherein the non-conductive peripheral structure rests on the wafer support.  
   
   
       10 . The stripping reactor of  claim 6  wherein the wafer support assembly further comprises a second conductive peripheral structure that rests on the wafer support inside the non-conductive peripheral structure.  
   
   
       11 . The stripping reactor of  claim 6  wherein the wafer support comprises a conductive structure disposed about its periphery.  
   
   
       12 . The stripping reactor of  claim 2  wherein the gas distribution plate is a showerhead comprised of aluminum.  
   
   
       13 . The stripping reactor of  claim 1  wherein the gas distribution plate is a showerhead comprised of SiC.  
   
   
       14 . The stripping reactor of  claim 13  wherein the gas distribution plate is surrounded by a conductor.  
   
   
       15 . The stripping reactor of  claim 14  wherein the conductor is aluminum or titanium.  
   
   
       16 . The stripping reactor of  claim 1  which further comprises a gas distribution plenum that receives the gas output from the remote plasma source, and wherein one side of the gas distribution plenum is comprised of the gas distribution plate.  
   
   
       17 . The stripping reactor of  claim 16  wherein the gas distribution plenum is lined with quartz.  
   
   
       18 . The stripping reactor of  claim 16  wherein the distance between a gas inlet and the gas distribution plate is in a range from about 0.5 to about 2.0 inches.  
   
   
       19 . The stripping reactor of  claim 1  wherein a distance between a top of the wafer support and the gas distribution plate is in a range from about 0.5 to about 3 inches.  
   
   
       20 . The stripping reactor of  claim 1  that further includes a gas accumulator that stores gas used to vent the processing chamber.  
   
   
       21 . The stripping reactor of  claim 15  wherein the gas accumulator has a volume in a range from about 1 L to about 10 L.  
   
   
       22 . The stripping reactor of  claim 1  which further comprises a slit-valve cut-out, and a slit-valve door disposed within the processing chamber adapted to be moved to close the slit-valve cut-out.  
   
   
       23 . The stripping reactor of  claim 1  wherein the wafer support comprises aluminum.  
   
   
       24 . The stripping reactor of  claim 23  wherein the wafer support is surrounded by an insulator ring.  
   
   
       25 . The stripping reactor of  claim 24  wherein the wafer support rests in an insulator base.  
   
   
       26 . The stripping reactor of  claim 25  wherein the insulator ring comprises quartz and the insulator base comprises alumina.  
   
   
       27 . The stripping reactor of  claim 1  wherein the gas distribution plate comprises quartz.  
   
   
       28 . The stripping reactor of  claim 1  wherein inner surfaces of the processing chamber comprise a conductive material.  
   
   
       29 . The stripping reactor of  claim 1  where the wafer support includes channels and the stripping reactor further includes a heat exchanger to pump heat exchange fluid through the channels.  
   
   
       30 . The stripping reactor of  claim 1  which further comprises an endpoint detector sensitive to radiation at one or more of the following wavelengths: about 777 nm and about 656 nm.  
   
   
       31 . A plasma processing reactor for processing a wafer to fabricate at least a portion of an integrated circuit that comprises: 
 a grounded gas distribution plate that transmits gas into a processing chamber;    a wafer support to support the wafer;    a wafer support assembly disposed about the wafer support that includes an outer conductive peripheral structure connected to ground; and    an RF power supply that supplies RF power to the wafer support.    
   
   
       32 . The plasma processing reactor of  claim 31  wherein the gas distribution plate is conductive.  
   
   
       33 . The plasma processing reactor of  claim 32  wherein the processing chamber comprises a grounded chamber body.  
   
   
       34 . The plasma processing reactor of claim of  claim 32  wherein the gas distribution plate is a showerhead.