Multi-piece baffle plate assembly for a plasma processing system

Abstract

A plasma processing system includes at least one multi-piece baffle plate. The multi-piece baffle plate assembly generally comprises at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening. The individual pieces can be formed of a ceramic material. The effects caused by thermal gradients in the plate during plasma processing are minimized.

1 . A baffle plate assembly for distributing plasma into an adjacent process chamber containing a semiconductor wafer to be processed, comprising: 
 a generally planar multi-piece baffle plate spaced apart from and fixedly positioned above a wafer to be processed.    
     
     
         2 . The baffle plate assembly of  claim 1 , wherein the generally planar multi-piece baffle plate comprises at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.  
     
     
         3 . The baffle plate assembly of  claim 2 , wherein the opening comprises an annular recessed portion and the insert portion comprises a lip adapted to seat on the annular recessed portion.  
     
     
         4 . The baffle plate assembly of  claim 3 , wherein the annular recessed portion further comprises at least three pins spaced equidistantly about the annular recessed portion, wherein the insert portion is supported by the at least three pins.  
     
     
         5 . The baffle plate assembly of  claim 1 , wherein the multi-piece baffle plate comprises a non-apertured central portion.  
     
     
         6 . The baffle plate assembly of  claim 1 , wherein the baffle plate assembly comprises an upper baffle plate and a lower baffle plate, wherein the upper baffle plate comprises the multi-piece baffle plate, wherein the multi-piece baffle plate has a non-apertured central portion.  
     
     
         7 . The baffle plate assembly of  claim 2 , wherein the annular shaped ring and the insert portion form a gap less than 0.010 inches.  
     
     
         8 . The baffle plate assembly of  claim 1 , wherein the multi-piece baffle plate is formed of a ceramic material.  
     
     
         9 . A plasma processing chamber for processing a semiconductor wafer contained therein, comprising: 
 a wafer processing cavity into which a wafer may be inserted for processing, the wafer processing cavity defined in part by walls including a top wall; and    a baffle plate assembly located adjacent said wafer processing cavity for distributing energized gas thereinto, said baffle plate assembly comprising a generally planar upper baffle plate fixedly positioned above a generally planar lower baffle plate, said upper baffle plate comprising at least two pieces comprising at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.    
     
     
         10 . The plasma processing chamber of  claim 9 , wherein said upper baffle plate is comprised of a ceramic material.  
     
     
         11 . The plasma processing chamber of  claim 9 , wherein the opening comprises an annular recessed portion and the insert portion comprises a lip adapted to seat on the annular recessed portion.  
     
     
         12 . The plasma processing chamber of  claim 11 , wherein the annular recessed portion further comprises at least three pins spaced equidistantly about the annular recessed portion, wherein the insert portion is supported by the at least three pins.  
     
     
         13 . The plasma processing chamber of  claim 9 , wherein the upper baffle plate comprises a non-apertured central portion.  
     
     
         14 . The plasma processing chamber of  claim 9 , wherein the annular shaped ring and the insert portion form a gap less than 0.010 inches.  
     
     
         15 . The plasma processing chamber of  claim 9 , wherein the chamber is adapted to receive a wafer having a diameter of at least 200 millimeters.  
     
     
         16 . A downstream plasma treatment device for treating a substrate, comprising, in combination: 
 a gas source;    a plasma generating component in fluid communication with the gas source, the plasma generating component comprising a plasma tube and a plasma generator coupled to the plasma tube for generating a plasma within the plasma tube from the gas source; and    a process chamber in fluid communication with the plasma tube, wherein the process chamber comprises a baffle plate assembly comprising a generally planar multi-piece baffle plate spaced apart from and fixedly positioned above the substrate to be processed.    
     
     
         17 . The downstream plasma treatment device of  claim 16 , wherein the multi-piece baffle plate is formed of a ceramic material.  
     
     
         18 . The downstream plasma treatment device of  claim 16 , wherein the generally planar multi-piece baffle plate comprises at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.  
     
     
         19 . The downstream plasma treatment device of  claim 18 , wherein the opening comprises an annular recessed portion and the insert portion comprises a lip adapted to seat on the annular recessed portion.  
     
     
         20 . The downstream plasma treatment device of  claim 19 , wherein the annular recessed portion further comprises at least three pins spaced equidistantly about the annular recessed portion, wherein the insert portion is supported by the at least three pins.  
     
     
         21 . The downstream plasma treatment device of  claim 16 , wherein the multi-piece baffle plate comprises a non-apertured central portion.  
     
     
         22 . The downstream plasma treatment device of  claim 18 , wherein the annular shaped ring and the insert portion form a gap less than 0.010 inches.  
     
     
         23 . A downstream plasma treatment device for treating a substrate, comprising, in combination: 
 a gas source;    a plasma generating component in fluid communication with the gas source, the plasma generating component comprising a plasma tube and a plasma generator coupled to the plasma tube for generating a plasma within the plasma tube from the gas source; and    a process chamber in fluid communication with the plasma tube, wherein the process chamber comprises a baffle plate assembly comprising a generally planar upper baffle plate fixedly positioned above a generally planar lower baffle plate, said upper baffle plate comprising at least two pieces comprising at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.    
     
     
         24 . The downstream plasma treatment device of  claim 23 , wherein the upper baffle plate is formed of a ceramic material.  
     
     
         25 . The downstream plasma treatment device of  claim 23 , wherein the upper baffle plate comprises at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.  
     
     
         26 . The downstream plasma treatment device of  claim 25 , wherein the opening comprises an annular recessed portion and the insert portion comprises a lip adapted to seat on the annular recessed portion.  
     
     
         27 . The downstream plasma treatment device of  claim 26 , wherein the annular recessed portion further comprises at least three pins spaced equidistantly about the annular recessed portion, wherein the insert portion is supported by the at least three pins.  
     
     
         28 . The downstream plasma treatment device of  claim 23 , wherein the upper baffle plate comprises a non-apertured central portion.  
     
     
         29 . The downstream plasma treatment device of  claim 25 , wherein the annular shaped ring and the insert portion form a gap less than 0.010 inches.  
     
     
         30 . A method for preventing cracking of a ceramic baffle plate having a radius greater than 4 inches during a plasma mediated process, wherein the plasma mediated process subjects the ceramic baffle plate to a thermal temperature gradient across the plate, the method comprising: 
 forming the ceramic baffle plate into at least two pieces, wherein a gap formed by the at least two pieces is less than 0.010 inches; and    exposing the least two pieces of the ceramic baffle plate to plasma formed during the plasma mediated process.    
     
     
         31 . The method of  claim 30 , wherein the at least two pieces comprises at least one annular shaped ring portion having an opening and an insert portion dimensioned to sit within the opening.  
     
     
         32 . The method of  claim 30 , wherein exposing the at least two pieces of the ceramic baffle plate to plasma subjects the at least two pieces to hoop stresses less than a material stress for the ceramic.