Coating architecture for plasma sprayed chamber components

Abstract

A method of plasma spraying an article comprises inserting the article into a vacuum chamber for a low pressure plasma spraying system. A low pressure plasma spray process is then performed by the low pressure plasma spraying system to form a first plasma resistant layer having a thickness of 20-500 microns and a porosity of over 1%. A plasma spray thin film, plasma spray chemical vapor deposition or plasma spray physical vapor deposition process is then performed by the low pressure plasma spraying system to deposit a second plasma resistant layer on the first plasma resistant layer, the second plasma resistant layer having a thickness of less than 50 microns and a porosity of less than 1%.

What is claimed is: 
     
         1 . A method of plasma spraying an article comprising:
 inserting the article into a vacuum chamber for a low pressure plasma spraying system;   performing a low pressure plasma spray (LPPS) process by the low pressure plasma spraying system to form a first plasma resistant ceramic layer on the article, the first plasma resistant ceramic layer having a thickness of 20-500 microns and a porosity of over 1%; and   performing a plasma spray chemical vapor deposition (PSCVD) process by the low pressure plasma spraying system to deposit a second plasma resistant ceramic layer on the first plasma resistant ceramic layer, the second plasma resistant ceramic layer having a thickness of approximately 1-50 microns and a porosity of less than 1%.   
     
     
         2 . The method of  claim 1 , wherein the first plasma resistant ceramic layer and the second plasma resistant ceramic layer each comprise at least one of Y 3 Al 5 O 12 , Y 4 Al 2 O 9 , Er 2 O 3 , Gd 2 O 3 , Y 2 O 3 , Er 3 Al 5 O 12 , Gd 3 Al 5 O 12 , YF 3 , Nd 2 O 3 , or a ceramic compound comprising Y 4 Al 2 O 9  and a solid-solution of Y 2 O 3 —ZrO. 
     
     
         3 . The method of  claim 1 , wherein the first plasma resistant ceramic layer consists of a rare earth oxide and the second plasma resistant ceramic layer consists of the rare earth oxide. 
     
     
         4 . The method of  claim 1 , wherein the first plasma resistant ceramic layer comprises a coloring agent. 
     
     
         5 . The method of  claim 1 , wherein the article is a chamber component comprising at least one of a metal or a sintered ceramic. 
     
     
         6 . The method of  claim 1 , wherein a first set of plasma spray parameters are used while performing the LPPS process and a second set of plasma spray parameters are used while performing the PSCVD process. 
     
     
         7 . The method of  claim 1 , wherein the LPPS process and the PSCVD process are performed in the vacuum chamber as part of a single plasma spray recipe. 
     
     
         8 . The method of  claim 1 , wherein:
 performing the LPPS process comprises reducing a pressure of the vacuum chamber to about 20-200 mbar and injecting a powder feedstock into a plasma jet; and   performing the PSCVD process comprises reducing the pressure of the vacuum chamber to about 0.1-1.0 mbar, setting a power of the low pressure plasma spraying system to less than about 10 kW, and injecting a liquid feedstock or a vapor feedstock into the plasma jet.   
     
     
         9 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 40-60 mol %, ZrO 2  in a range of 32-50 mol %, and Al 2 O 3  in a range of 10-20 mol %. 
     
     
         10 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 40-49 mol %, ZrO 2  in a range of 20-40 mol %, and Al 2 O 3  in a range of 20-40 mol %. 
     
     
         11 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 76-90 mol %, ZrO 2  in a range of 1-20 mol %, and Al 2 O 3  in a range of 10-20 mol %. 
     
     
         12 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 76-90 mol %, ZrO 2  in a range of 1-20 mol %, and Al 2 O 3  in a range of 10-20 mol %. 
     
     
         13 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 40-60 mol %, ZrO 2  in a range of 1-20 mol %, and Al 2 O 3  in a range of 31-40 mol %. 
     
     
         14 . The method of  claim 1 , wherein at least one of the first plasma resistant ceramic layer or the second plasma resistant ceramic layer comprises Y 2 O 3  in a range of 40-45 mol %, ZrO 2  in a range of 0-10 mol %, Er 2 O 3  in a range of 35-40 mol %, Gd 2 O 3  in a range of 5-10 mol %, and SiO 2  in a range of 5-15 mol %. 
     
     
         15 . The method of  claim 1 , wherein the first plasma resistant ceramic layer consists essentially of a first ceramic selected from a group consisting of Y 4 Al 2 O 9 , Er 2 O 3 , Er 3 Al 5 O 12  or Gd 3 Al 5 O 12  and the second plasma resistant ceramic layer consists essentially of the first ceramic or a second ceramic selected from the group consisting of Y 3 Al 5 O 12 , Y 4 Al 2 O 9 , Er 2 O 3 , Gd 2 O 3 , Y 2 O 3 , Er 3 Al 5 O 12 , Gd 3 Al 5 O 12 , YF 3 , Nd 2 O 3 , or a ceramic compound comprising Y, Al, O and Zr. 
     
     
         16 . The method of  claim 1 , wherein the first plasma resistant ceramic layer and the second plasma resistant ceramic layer each consists essentially of Y 3 Al 5 O 12  or Y 4 Al 2 O 9 . 
     
     
         17 . The method of  claim 1 , wherein the first plasma resistant ceramic layer and the second plasma resistant ceramic layer each consists essentially of Er 2 O 3 . 
     
     
         18 . The method of  claim 1 , wherein the first plasma resistant ceramic layer and the second plasma resistant ceramic layer each consists essentially of a ceramic compound consisting of Y 4 Al 2 O 9  and a solid-solution of Y 2 O 3 —ZrO 2 . 
     
     
         19 . A method of plasma spraying an article comprising:
 inserting the article into a vacuum chamber for a low pressure plasma spraying system;   performing a low pressure plasma spray (LPPS) process by the low pressure plasma spraying system to form a first plasma resistant ceramic layer on the article, the first plasma resistant ceramic layer having a thickness of 20-500 microns and a porosity of over 1%; and   performing a plasma spray physical vapor deposition (PSPVD) process by the low pressure plasma spraying system to deposit a second plasma resistant ceramic layer on the first plasma resistant ceramic layer, the second plasma resistant ceramic layer having a thickness of about 10-100 microns and a porosity of less than 1%.   
     
     
         20 . The method of  claim 19 , wherein performing the LPPS process comprises feeding a powder having a particular composition into a plasma jet, and wherein performing the PSPVD process comprises feeding the powder having the particular composition into the plasma jet.