Substrate support assembly having a plasma resistant protective layer

Abstract

A substrate support assembly comprises a ceramic body and a thermally conductive base bonded to a lower surface of the ceramic body. The substrate support assembly further comprises a protective layer covering an upper surface of the ceramic body, wherein the protective layer comprises at least one of yttrium aluminum garnet (YAG) or a ceramic compound comprising Y 4 Al 2 O 9 and a solid-solution of Y 2 O 3 —ZrO 2 .

1 .- 11 . (canceled) 
     
     
         12 . A method comprising:
 providing a ceramic body;   bonding a thermally conductive base to lower surface of the ceramic body;   performing an ion assisted deposition (IAD) process or a plasma spray process to deposit a protective layer on the upper surface of the ceramic body, the protective layer comprising at least one of yttrium aluminum garnet (YAG) or a ceramic compound of Y 4 Al 2 O 9  and a solid-solution of Y 2 O 3 —ZrO 2 ;   forming a plurality of mesas on at least one of an upper surface of the ceramic body or the protective layer; and   forming a plurality of holes in at least one of the ceramic body or the protective layer.   
     
     
         13 . The method of  claim 12 , wherein the IAD process is preformed to deposit the protective layer, wherein the plurality of mesas are formed on the upper surface of the ceramic body and the plurality of holes are formed in the ceramic body prior to performing the IAD process, and wherein the protective layer telegraphs the plurality of mesas and does not plug the plurality of holes. 
     
     
         14 . The method of  claim 13 , wherein the protective layer has a porosity below 1%, a thickness of less than 20 microns, and a breakdown voltage of greater than 1000 V/mil. 
     
     
         15 . The method of  claim 13 , wherein the ceramic body is an electrostatic puck, the upper surface of the ceramic body is not roughened prior to performing the IAD process, and a curvature over the lower surface of the electrostatic puck is less than 50 micron after performing the IAD process. 
     
     
         16 . The method of  claim 12 , wherein the plasma spray process is performed to deposit the plasma protective layer, the plurality of mesas are formed on an upper surface of the protective layer and the plurality of holes are formed in the ceramic body and the protective layer, the method further comprising roughening the upper surface of the ceramic body prior to the plasma spray process. 
     
     
         17 . The method of  claim 16 , wherein the protective layer has a thickness of 100-300 microns, a porosity of 2-5% and a breakdown voltage of up to 1200 V/mil. 
     
     
         18 .- 20 . (canceled) 
     
     
         21 . The method of  claim 12 , wherein the upper surface of the ceramic body is non-roughened. 
     
     
         22 . The method of  claim 12 , wherein the upper surface of the ceramic body is roughened. 
     
     
         23 . The method of  claim 12 , further comprising diffusion bonding a bulk sintered ceramic article to the upper surface of the ceramic body via an interface layer. 
     
     
         24 . The method of  claim 23 , wherein the ceramic body comprises Al 2 O 3  and the interface layer comprises Y 3 Al 5 O 12  (YAG). 
     
     
         25 . The method of  claim 23 , wherein the bulk sintered ceramic article has a hardness between about 14 GPa and about 16 GPa.