Plasma resistant coating of porous body by atomic layer deposition

1. An article comprising:

a porous body comprising a plurality of pores within the porous body, the plurality of pores each comprising pore walls, wherein the porous body is permeable to a gas; and

a plasma resistant coating on a surface of the porous body and on the pore walls of the plurality of pores within the porous body, the plasma resistant coating having a thickness of about 5 nm to about 3 μm, wherein the plasma resistant coating protects the pore walls from erosion by a fluorine plasma, wherein the porous body with the plasma resistant coating remains permeable to the gas, wherein the plasma resistant coating has an approximately zero porosity and has a uniform thickness having a thickness variation of less than ±20%, and

wherein the plasma resistant coating consists essentially of:

a high purity metal oxide layer, wherein the high purity metal oxide layer is aluminum oxide; and

a rare earth metal-containing oxide layer consisting essentially of a material selected from a group consisting of Y 2 O 3 , Er 2 O 3 , Y 3 Al 5 O 12 (YAG), ZrO 2 , Gd 2 O 3 , a combination of any two of Y 2 O 3 , Er 2 O 3 and ZrO 2 , a solid solution of Y 2 O 3 —ZrO 2 , and a ceramic compound comprising Y 4 Al 2 O 9 and a solid-solution of Y 2 O 3 —ZrO 2 ,

wherein the article is a chamber component for a semiconductor processing chamber.

2. The article of claim 1 , wherein the article is a ceramic plug for an electrostatic chuck.

3. The article of claim 1 , wherein the porous body has a porosity of about 5% to about 60%.

4. The article of claim 1 , wherein the plasma resistant coating consists essentially of:

a stack of alternating layers of a first type of layer and a second type of layer, wherein:

the first type of layer is the at least one high purity metal oxide layer having a thickness of about 1 angstrom to about 20 angstroms; and

the second type of layer is the at least one rare earth metal-containing oxide having a thickness of about 5 angstroms to about 100 angstroms.

5. The article of claim 1 , wherein the porous body consists essentially of a two phase material consisting essentially of sintered particles of a first oxide and a second oxide that acts as a binder for the sintered particles of the first oxide, wherein the first oxide is selected from a group consisting of aluminum oxide and aluminum nitride and the second oxide is silicon dioxide.

6. The article of claim 1 , wherein the porous body is selected from a group consisting of a) a mixture of aluminum oxide and silicon dioxide, b) a mixture of aluminum oxide, magnesium oxide and silicon dioxide, c) silicon carbide, d) silicon nitride and e) a mixture of aluminum nitride and silicon dioxide.

7. A method comprising:

performing atomic layer deposition to deposit a plasma resistant coating on a porous chamber component comprising a plurality of pores, the plurality of pores each comprising pore walls, wherein the porous body is permeable to a gas, wherein the plasma resistant coating consists essentially of:

a high purity metal oxide layer, wherein the high purity metal oxide layer is aluminum oxide; and

a rare earth metal-containing oxide layer consisting essentially of a material selected from a group consisting of Y 2 O 3 , Er 2 O 3 , Y 3 Al 5 O 12 (YAG), ZrO 2 , Gd 2 O 3 , a combination of any two of Y 2 O 3 , Er 2 O 3 and ZrO 2 , a solid solution of Y 2 O 3 —ZrO 2 , and a ceramic compound comprising Y 4 Al 2 O 9 and a solid-solution of Y 2 O 3 —ZrO 2 , and wherein performing the atomic layer deposition comprises:

depositing the plasma resistant coating onto a surface of the porous chamber component; and

depositing the plasma resistant coating onto the pore walls of the plurality of pores within the porous chamber component;

the plasma resistant coating having a thickness of about 5 nm to about 3 μm, wherein the plasma resistant coating protects the pore walls from erosion by a fluorine plasma, wherein the porous chamber component with the plasma resistant coating remains permeable to the gas after performing the atomic layer deposition, wherein the plasma resistant coating has an approximately zero porosity, and

wherein the porous chamber component is a component for a semiconductor processing chamber.

8. The method of claim 7 , wherein the aluminum oxide has a purity of about 89.99% to about 99.99%.

9. The method of claim 7 , wherein the plasma resistant coating consists essentially of the aluminum oxide and the rare earth metal containing oxide, and wherein depositing the plasma resistant coating comprises:

performing a deposition cycle comprising:

injecting an aluminum-containing precursor into a deposition chamber containing the chamber component to cause the aluminum-containing precursor to adsorb onto the pore walls to form a first half reaction; and

injecting an oxygen-containing reactant into the deposition chamber to form a second half reaction; and

repeating the deposition cycle one or more times until a target thickness is achieved.

10. The method of claim 7 , wherein the rare earth metal containing oxide layer consists essentially of a stack of alternating layers of a) a zirconium-, erbium- or aluminum-containing oxide and b) a yttrium-containing oxide, and wherein depositing the rare earth metal containing oxide layer comprises alternating deposition of the yttrium-containing oxide and the zirconium-, erbium- or aluminum-containing oxide to form a single phase or multi-phase yttrium-containing oxide by:

performing a deposition cycle comprising:

injecting a yttrium-containing precursor into a deposition chamber containing the chamber component to cause the yttrium-containing precursor to adsorb onto the pore walls to form a first half reaction;

injecting an oxygen-containing reactant into the deposition chamber to form a second half reaction and a first layer;

injecting an additional zirconium-, erbium- or aluminum-containing precursor into the deposition chamber to cause the additional zirconium-, erbium- or aluminum-containing precursor to adsorb onto a surface of the first layer to form a third half reaction; and

injecting the oxygen-containing reactant or an alternative oxygen-containing reactant into the deposition chamber to form a fourth half reaction and a second layer; and

repeating the deposition cycle one or more times until a target thickness is reached.

11. The method of claim 7 , wherein depositing the rare earth metal containing oxide layer comprises codepositing a yttrium-containing oxide and one or more additional zirconium-, erbium- or aluminum-containing oxide to form a single phase or multi-phase yttrium-containing oxide by:

performing a deposition cycle comprising:

co-injecting a mixture of a first precursor for the yttrium-containing oxide and a second precursor for the additional zirconium-, erbium- or aluminum-containing oxide into a deposition chamber containing the chamber component to cause the first precursor and the second precursor to adsorb onto the pore walls to form a first half reaction; and

injecting an oxygen-containing reactant into the deposition chamber to form a second half reaction; and

repeating the deposition cycle one or more times until a target thickness is reached.

12. The method of claim 7 , wherein the porous chamber component consists essentially of a two phase material comprising sintered particles of a first oxide and a second oxide that acts as a binder for the sintered particles of the first oxide, wherein the first oxide is selected from a group consisting of aluminum oxide and aluminum nitride and the second oxide is silicon dioxide.

13. The method of claim 7 , wherein the porous chamber component is a plug for an electrostatic chuck.

14. The method of claim 7 , further comprising:

determining at least one of an initial porosity or an initial permeability of the porous chamber component;

determining at least one of a target porosity or a target permeability for the porous chamber component; and

determining a target thickness of the plasma resistant coating that will reduce at least one of the initial porosity to the target porosity or the initial permeability to the target permeability, wherein the plasma resistant coating has the target thickness.

15. A method comprising:

loading a plurality of porous ceramic plugs together into a deposition chamber, each porous ceramic plug comprising a plurality of pores, each pore comprising a pore wall, wherein each porous ceramic plug is permeable to a gas; and

forming a plasma resistant coating on a surface of each porous ceramic plug and a plurality of pore walls, consisting essentially of:

performing atomic layer deposition to deposit an aluminum oxide layer on each porous ceramic plug concurrently, wherein performing the atomic layer deposition consists essentially of:

depositing the aluminum oxide layer onto a surface of each porous ceramic plug; and

depositing the aluminum oxide layer onto the plurality of pore walls; and

performing atomic layer deposition to deposit a rare earth metal-containing oxide layer on the plurality of porous ceramic plugs concurrently, wherein the rare earth metal-containing oxide consists essentially of a material selected from a group consisting of Y 2 O 3 , Er 2 O 3 , Y 3 Al 5 O 12 (YAG), ZrO 2 , Gd 2 O 3 , a combination of any two of Y 2 O 3 , Er 2 O 3 and ZrO 2 , a solid solution of Y 2 O 3 —ZrO 2 , and a ceramic compound comprising Y 4 Al 2 O 9 and a solid-solution of Y 2 O 3 —ZrO 2 , and wherein performing the atomic layer deposition of the rare earth metal containing oxide layer consists essentially of:

depositing the rare earth metal-containing oxide layer onto the aluminum oxide layer of each porous ceramic plug; and

depositing the rare earth metal-containing oxide layer onto the aluminum oxide layer of the plurality of pore walls;

wherein the aluminum oxide layer has a thickness of about 5 nm to about 3 μm, wherein the plasma resistant coating protects the pore walls from erosion by a fluorine plasma, and wherein the porous ceramic plug with the plasma resistant coating remains permeable to the gas after performing the atomic layer deposition, wherein the plasma resistant coating has an approximately zero porosity, and

wherein the plurality of porous ceramic plugs are components for a semiconductor processing chamber.

16. The article of claim 1 , wherein the rare earth metal-containing oxide layer consists essentially of a combination of Er 2 O 3 and ZrO 2 , a combination of Y 2 O 3 and Er 2 O 3 , Y 3 Al 5 O 12 (YAG) or Gd 2 O 3 .

17. The article of claim 7 , wherein the rare earth metal-containing oxide layer consists essentially of a combination of Er 2 O 3 and ZrO 2 , a combination of Y 2 O 3 and Er 2 O 3 , Y 3 Al 5 O 12 (YAG) or Gd 2 O 3 .

18. The article of claim 15 , wherein the rare earth metal-containing oxide layer consists essentially of a combination of Er 2 O 3 and ZrO 2 , a combination of Y 2 O 3 and Er 2 O 3 , Y 3 Al 5 O 12 (YAG) or Gd 2 O 3 .