Plasma thermal shield for heat dissipation in plasma chamber

Abstract

Methods of and apparatuses for dicing semiconductor wafers, each wafer having a plurality of integrated circuits, are described. In an example, a plasma thermal shield for a plasma processing chamber includes an annular ring body having an inner opening. A plasma-facing surface of the annular ring body has a general topography. A bottom surface of the annular ring body reciprocates the general topography with recessed regions disposed therein, providing one or more protruding regions at the bottom surface of the annular ring body.

1 . A plasma thermal shield for a plasma processing chamber, the plasma thermal shield comprising:
 an annular ring body having an inner opening;   a plasma-facing surface of the annular ring body, the plasma-facing surface having a general topography; and   a bottom surface of the annular ring body, the bottom surface reciprocating the general topography with recessed regions disposed therein, providing one or more protruding regions at the bottom surface of the annular ring body.   
     
     
         2 . The plasma thermal shield of  claim 1 , wherein a total surface area of the recessed regions is approximately in the range of 85-92% of a total surface area of the bottom surface of the annular ring body. 
     
     
         3 . The plasma thermal shield of  claim 1 , wherein the general topography comprises an outer surface raised above an inner surface and coupled to the inner surface by a sloping surface. 
     
     
         4 . The plasma thermal shield of  claim 3 , wherein the one or more protruding regions comprise a first protruding region reciprocal to the outer surface, a second protruding region reciprocal to the sloping surface, and a third first protruding region reciprocal to the inner surface. 
     
     
         5 . The plasma thermal shield of  claim 1 , wherein the recessed regions have a depth or approximately 1/16 th  of an inch into the annular ring body, leaving approximately 1/16 th  of an inch of the annular ring body remaining at the recessed regions. 
     
     
         6 . The plasma thermal shield of  claim 1 , wherein the annular ring body comprises a material selected from the group consisting of alumina (Al 2 O 3 ), yttria (Y 2 O 3 ), silicon nitride (SiN) and silicon carbide (SiC). 
     
     
         7 . A shadow ring assembly for a plasma processing chamber, the shadow ring assembly comprising:
 a shadow ring having an annular body and an inner opening; and   a plasma thermal shield nested on the shadow ring, the plasma thermal shield comprising:
 an annular ring body having an inner opening approximately the same size, and aligned with, the inner opening of the shadow ring; 
 a plasma-facing surface of the annular ring body, the plasma-facing surface having a general topography; and 
 a bottom surface of the annular ring body, the bottom surface reciprocating the general topography with recessed regions disposed therein, providing one or more protruding regions at the bottom surface of the annular ring body, the one or more protruding regions in contact with the shadow ring. 
   
     
     
         8 . The shadow ring assembly of  claim 7 , wherein the plasma thermal shield prevents contact of the underlying shadow ring with a hot surface or acts as a heat deflector for the underlying shadow ring. 
     
     
         9 . The shadow ring assembly of  claim 7 , wherein a total surface area of the recessed regions of the plasma thermal shield is approximately in the range of 85-92% of a total surface area of the bottom surface of the annular ring body of the plasma thermal shield. 
     
     
         10 . The shadow ring assembly of  claim 7 , wherein the general topography of the plasma-facing surface of the annular ring body of the plasma thermal shield comprises an outer surface raised above an inner surface and coupled to the inner surface by a sloping surface. 
     
     
         11 . The shadow ring assembly of  claim 7 , wherein the recessed regions of the plasma thermal shield have a depth or approximately 1/16 th  of an inch into the annular ring body of the of the plasma thermal shield, leaving approximately 1/16 th  of an inch of the annular ring body remaining at the recessed regions. 
     
     
         12 . The shadow ring assembly of  claim 7 , wherein the annular ring body of the plasma thermal shield comprises a material selected from the group consisting of alumina (Al 2 O 3 ), yttria (Y 2 O 3 ), silicon nitride (SiN) and silicon carbide (SiC). 
     
     
         13 . The shadow ring assembly of  claim 7 , wherein the shadow ring further comprises a cooling channel disposed in the annular body of the shadow ring for cooling fluid transport, the cooling channel coupled to a pair of supply/return openings at a surface of the annular body of the shadow ring. 
     
     
         14 - 20 . (canceled)