Substrate support and method of fabricating the same

Abstract

A substrate support and method of fabricating the same are provided. Generally, one method of fabrication includes assembling a subassembly comprising a first reinforcing member and a heating element, supporting the subassembly at least 40 mm from a bottom of a mold, encapsulating the supported subassembly with molten aluminum, and applying pressure to the molten aluminum. Alternatively, a method of fabrication includes assembling a subassembly comprising a stud disposed through a heating element sandwiched between a first reinforcing member and a second reinforcing member, supporting the subassembly above a bottom of a mold, encapsulating the subassembly disposed in the mold with molten aluminum to form a casting, forming a hole in the casting by removing at least a portion of the stud, and disposing a plug in at least a portion of the hole.

What is claimed is:  
     
         1 . A method of fabricating a substrate support comprising: 
 disposing a first reinforcing member and a heating element on a stud to form a subassembly;    encapsulating the subassembly in a mold with molten aluminum to form a casting; and    finishing the casting by removing at least a portion of the stud.    
     
     
         2 . The method of  claim 1 , wherein the disposing step further comprises: 
 sandwiching the heater element between the first reinforcing member and a second reinforcing member; and    coupling a backplate to the second reinforcing member and having at least 40 μm spacing therebetween.    
     
     
         3 . The method of  claim 1 , wherein the disposing step further comprises: 
 sandwiching the heater element between the first reinforcing member and a second reinforcing member.    
     
     
         4 . The method of  claim 3 , wherein the encapsulation step further comprises: 
 impregnating the first reinforcing member and the second reinforcing member with aluminum.    
     
     
         5 . The method of  claim 1 , wherein the encapsulating step further comprises: 
 supporting the subassembly at least  40  mm from a bottom of the mold or a backplate coupled to the subassembly; and    applying pressure to the molten aluminum.    
     
     
         6 . The method of  claim 1 , wherein the applying step further comprises: 
 applying pressure to the molten aluminum to an area of the molten aluminum at least directly above the subassembly.    
     
     
         7 . The method of  claim 1 , wherein the encapsulation step further comprises: 
 impregnating the first reinforcing member with aluminum.    
     
     
         8 . The method of  claim 1 , wherein the encapsulating step further comprises: 
 providing the entire amount of molten aluminum into the mold in one shot.    
     
     
         9 . The method of  claim 1 , wherein the finishing step further comprises: 
 annealing the casting;    removing aluminum from at least a portion of the casting to form an unfinished support; and    anodizing the unfinished support.    
     
     
         10 . The method of  claim 1 , wherein the finishing step further comprises: 
 filling a void left in the aluminum by the removed portion of the stud with an aluminum plug.    
     
     
         11 . The method of  claim 1 , wherein the first reinforcing member is comprised of metal or ceramic.  
     
     
         12 . The method of  claim 1  wherein the first reinforcing member is comprised of a ceramic material selected from the group consisting of aluminum oxide plate, aluminum oxide fiber and aluminum oxide particle combined with silicon oxide fiber, silicon oxide particle, silicon carbide fiber or silicon carbide particle.  
     
     
         13 . A method of fabricating a substrate support comprising: 
 assembling a subassembly comprising a stud disposed through a heating element sandwiched between a first reinforcing member and a second reinforcing member;    supporting the subassembly above a bottom of a mold;    encapsulating the subassembly in the mold with molten aluminum for form a casting;    forming a hole in the casting by removing at least a portion of the stud; and    disposing a plug in at least a portion of the hole.    
     
     
         14 . The method of  claim 13 , wherein the step of assembling the subassembly further comprises coupling a backplate to the subassembly in a spaced-apart relation of at least 40 mm.  
     
     
         15 . A method of fabricating a substrate support comprising: 
 assembling a subassembly comprising a heating element held between a first reinforcing member and a second reinforcing member by a plurality of studs;    coupling a backplate to the subassembly in a spaced-apart relation of at least 40 mm;    casting the subassembly supported in a mold with molten aluminum in one shot;    applying pressure to the molten aluminum; and    removing at least a portion of the stud surrounding the casted subassembly.    
     
     
         16 . The method of  claim 15  further comprising: 
 applying a pressure of at least 40 MPa to the molten aluminum over an area of the molten aluminum at least directly above the subassembly.  
 
     
     
         17 . The method of  claim 15  further comprises heating the mold to between about 350 and about 400 degrees Celsius.  
     
     
         18 . The method of  claim 15  further comprising filling voids left in the aluminum by the removed portion of the studs with an aluminum plug.  
     
     
         19 . The method of  claim 15 , wherein the step of applying pressure further comprises impregnating the first reinforcing member and second reinforcing members with aluminum.  
     
     
         20 . The method of  claim 15  further comprising anodizing the substrate support.  
     
     
         21 . A substrate support comprising: 
 a casted aluminum body having an outer surface;    a heating element embedded in the body;    a first reinforcing member embedded in the body;    at least one holed formed within the body between the outer surface and at least the heating element or the first reinforcing member; and    a plug disposed in the hole between the outer surface and the heating element or the first reinforcing member.    
     
     
         22 . The substrate support of  claim 21 , wherein the casted aluminum body is formed in a single shot of aluminum.  
     
     
         23 . The substrate support of  claim 22 , wherein a stud maintains the heating element and the reinforcing member in a spaced-apart relation during casting and is at least partially removed from the hole before insertion of the plug.  
     
     
         24 . The substrate support of  claim 21 , wherein the plug is welded to the aluminum body.  
     
     
         25 . The substrate support of  claim 21  further comprising a second reinforcing member embedded in the body and sandwiching the heating element with the first reinforcing member.  
     
     
         26 . A substrate support fabricated by a process comprising: 
 disposing a first reinforcing member and a heating element on a stud to form a subassembly;    encapsulating the subassembly in a mold with molten aluminum to form a casting; and    finishing the casting by removing at least a portion of the stud.