Process chamber process kit with protective coating

Abstract

Embodiments described herein generally relate to a method and apparatus for fabricating a chamber component for a plasma process chamber. In one embodiment a chamber component used within a plasma processing chamber is provided that includes a metallic base material comprising a roughened non-planar first surface, wherein the roughened non-planar surface has an Ra surface roughness of between 4 micro-inches and 80 micro-inches, a planar silica coating formed over the roughened non-planar surface, wherein the planar silica coating has a surface that has an Ra surface roughness that is less than the Ra surface roughness of the roughened non-planar surface, a thickness between about 0.2 microns and about 10 microns, less than 1% porosity by volume, and contains less than 2E12 atoms/centimeters2 of aluminum.

1 . A method for fabricating a chamber component for use in a plasma processing environment, comprising:
 depositing a layer of silica on a metallic surface of a metallic body of a chamber component, wherein the metallic surface is a roughened non-planar surface having an average surface roughness (Ra) of about 4 micro-inches to about 80 micro-inches, and the depositing comprises:
 painting, spreading, or spraying the layer of silica on the metallic surface; and 
   positioning the metallic body and the layer of silica in a furnace;   annealing the layer of silica to relieve surface tension in the layer of silica, the annealing comprising:
 heating for about one hour at a temperature of about 200 degrees Celsius or less, 
   wherein:
 the layer of silica comprises a surface that has an Ra that is less than the Ra of the metallic surface, 
 the layer of silica comprises a thickness of about 0.2 microns to about 10 microns, and 
 aluminum atoms are blocked from leaching from the metallic body and into the layer of silica such that the surface of the layer of silica contains more than 0 atoms/centimeters 2  of aluminum and less than 2E 12  atoms/centimeters 2  of aluminum. 
   
     
     
         2 . The method of  claim 1 , wherein the layer of silica has less than about 1% porosity by volume. 
     
     
         3 . The method of  claim 1 , wherein the metallic surface comprises pits, and the deposition of the layer of silica fills in the pits. 
     
     
         4 . The method of  claim 1 , wherein the metallic body comprises aluminum. 
     
     
         5 . A method for fabricating a chamber component for use in a plasma processing environment, comprising:
 forming a body of the chamber component from a metal material, the body comprising a metallic surface that is a roughened non-planar surface having an average surface roughness (Ra) of about 4 micro-inches to about 80 micro-inches;   depositing a layer of silica on the metallic surface of the body; and   heating the layer of silica and the metal material, wherein:
 the layer of silica comprises a surface that has an Ra that is less than the Ra of the roughened non-planar surface, 
 the layer of silica comprises a thickness of about 0.2 microns to about 10 microns, and 
 the layer of silica has less than about 1% porosity by volume; and 
   blocking aluminum atoms from leaching from the body and into the layer of silica such that the surface of the layer of silica contains more than 0 atoms/centimeters 2  of aluminum and less than 2E 12  atoms/centimeters 2  of aluminum.   
     
     
         6 . The method of  claim 5 , wherein the metallic material comprises aluminum. 
     
     
         7 . The method of  claim 5 , wherein the metallic material comprises a gas distribution showerhead. 
     
     
         8 . The method of  claim 5 , wherein the metallic material comprises a nozzle assembly. 
     
     
         9 . The method of  claim 5 , wherein the metallic material comprises a baffle. 
     
     
         10 . The method of  claim 5 , wherein the metallic material comprises a liner. 
     
     
         11 . The method of  claim 10 , wherein the liner comprises a cathode liner. 
     
     
         12 . The method of  claim 5 , wherein the layer of silica and the metal material are heated for about an hour. 
     
     
         13 . The method of  claim 12 , wherein the heating is at a temperature of about 200 degrees Celsius. 
     
     
         14 . The method of  claim 5 , wherein the depositing comprises painting, spreading, or spraying the layer of silica on the metallic surface. 
     
     
         15 . A method, comprising:
 positioning a chamber component as part of a process chamber, the chamber component comprising:
 a metallic base material comprising a roughened non-planar surface, wherein the roughened non-planar surface is a metallic surface having an average surface roughness (Ra) of about 4 micro-inches to about 80 micro-inches, 
 a planar silica coating formed over the roughened non-planar surface, wherein:
 the planar silica coating comprises a surface that has an Ra that is less than the Ra of the roughened non-planar surface, 
 the planar silica coating comprises a thickness of about 0.2 microns to about 10 microns, 
 the planar silica coating has less than about 1% porosity by volume; 
 
   blocking aluminum atoms from leaching from the metallic base material and into the planar silica coating such that the surface of the planar silica coating contains more than 0 atoms/centimeters 2  of aluminum and less than 2E 12  atoms/centimeters 2  of aluminum;   plasma treating the process chamber with a plasma containing nitrogen or oxygen;   placing a substrate into the process chamber, wherein a stack is disposed on the substrate; and   plasma treating the stack disposed on the substrate.   
     
     
         16 . The method of  claim 15 , wherein the plasma containing nitrogen or oxygen is formed by introducing one or more gases into the process chamber and energizing the one or more gases. 
     
     
         17 . The method of  claim 16 , wherein the one or more gases comprise O 2 , N 2 , NH 3 , Ar, H 2 , He, or a combination thereof. 
     
     
         18 . The method of  claim 15 , wherein the plasma treating the stack comprises treating the stack with a plasma containing ammonia. 
     
     
         19 . The method of  claim 18 , wherein forming the plasma containing ammonia further comprises introducing a hydrogen containing gas and an inert gas into the process chamber and energizing the hydrogen containing gas and the inert gas. 
     
     
         20 . The method of  claim 15 , wherein the plasma treating the stack comprises treating the stack with a plasma containing nitrogen.