Heat treated ceramic substrate having ceramic coating

Patent metadata

Field	Value
Publication number	US-11279661-B2
Application number	US-201916378344-A
Country	US
Kind code	B2
Filing date	Apr 8, 2019
Priority date	Feb 22, 2012
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A heat treated ceramic article includes a ceramic substrate and a ceramic coating on the ceramic substrate. The ceramic coating is a non-sintered ceramic coating that has a different composition than the ceramic substrate. The heat treated ceramic article further includes a transition layer between the ceramic substrate and the ceramic coating, the transition layer comprising first elements from the ceramic coating that have reacted with second elements from the ceramic substrate, wherein the transition layer has a thickness of about 0.1 microns to about 5 microns.

First claim

What is claimed is:

1. A ceramic article comprising a ceramic substrate and a ceramic coating on the ceramic substrate, wherein the ceramic substrate comprises Al 2 O 3 and the ceramic coating comprises Y 4 Al 2 O 9 and a solid solution of Y 2 O 3 —ZrO 2 , the ceramic article having been prepared by a process comprising:
performing a thermal spraying process to form the ceramic coating on the ceramic substrate, the ceramic coating having an initial porosity and an initial amount of cracking;
heating the ceramic article to a temperature range between about 1000° C. and about 1800° C.;
performing heat treatment of the ceramic article at one or more temperatures within the temperature range for a duration to reduce a porosity of the ceramic coating to below the initial porosity and to reduce an amount of cracking of the ceramic coating to below the initial amount of cracking, wherein the ceramic article is heat treated at below a sintering temperature for the ceramic coating to prevent sintering of the ceramic coating, wherein the heat treatment causes the ceramic coating to react with the ceramic substrate to form a transition layer between the ceramic substrate and the ceramic coating, and wherein the duration and the temperature range cause the transition layer to have a thickness of about 1 micron to about 5 microns, wherein the transition layer comprises Y 3 Al 5 O 12 ; and
cooling the ceramic article after the heat treatment, wherein after the heat treatment the ceramic coating is not sintered, has a reduced amount of cracking that is below the initial amount of cracking, and has a reduced porosity that is below the initial porosity.

2. The ceramic article of claim 1 , wherein the ceramic coating additionally has an initial particle count and an initial adhesion strength, and wherein after the heat treatment the ceramic coating has a reduced particle count and an increased adhesion strength of about 12 Mega Pascals.

3. The ceramic article of claim 1 , wherein the ceramic article is a refurbished ceramic article that has been used in a plasma etch process, and wherein the heating, the performing of the heat treatment and the cooling have been performed after the plasma etch process to reduce an increased surface defect density caused by the plasma etch process.

4. The ceramic article of claim 3 , wherein the plasma etch process causes polymers to form on the ceramic article, wherein performing the heat treatment in the presence of oxygen dry cleans the ceramic article by causing the polymers to react with the oxygen to become gases, and wherein the refurbished ceramic article is substantially free of the polymers.

5. The ceramic article of claim 1 , wherein:
the heating is performed at a ramping rate of about 0.1° C. per minute to about 20° C. per minute; and
the duration of the heat treatment is of up to about 24 hours.

6. The ceramic article of claim 1 , wherein the heat treatment causes a grain size of the ceramic coating to increase, and wherein the duration and the temperature range are selected so that the ceramic coating has a target grain size.

7. A method comprising:
performing a thermal spraying process to form a ceramic coating on a ceramic article, wherein the ceramic article comprises Al 2 O 3 and the ceramic coating comprises Y 4 Al 2 O 9 and a solid solution of Y 2 O 3 —ZrO 2 , wherein the ceramic coating has an initial porosity and an initial amount of cracking;
heating the ceramic coating to a temperature range between about 1000° C. and about 1800° C.;
heat treating the ceramic coating at one or more temperatures within the temperature range for a duration to reduce a porosity and an amount of cracking of the ceramic coating, wherein the ceramic coating is heat treated at below a sintering temperature for the ceramic coating to prevent sintering of the ceramic coating, and wherein the heat treating causes the ceramic coating to react with the ceramic article to form a transition layer between the ceramic article and the ceramic coating, wherein the duration and the temperature range cause the transition layer to have a thickness of about 1 micron to about 5 microns, wherein the transition layer comprises Y 3 Al 5 O 12 ; and
cooling the ceramic coating after the heat treating, wherein after the heat treating the ceramic coating is not sintered, has a reduced amount of cracking that is below the initial amount of cracking, and has a reduced porosity that is below the initial porosity.

8. The method of claim 7 , wherein:
the heating is performed at a ramping rate of about 0.1-20° C., per minute; and
the duration of the heat treating is up to about 24 hours.

9. The method of claim 7 , wherein the ceramic coating additionally has an initial particle count and an initial adhesion strength, and wherein after the heat treating the ceramic coating has a reduced particle count and an increased adhesion strength.

10. The method of claim 7 , further comprising:
after the ceramic article has been used in a plasma etch process, repeating the heating, the heat treating and the cooling to reduce an increased surface defect density caused by the plasma etch process.

11. The method of claim 10 , wherein the plasma etch process causes polymers to form on the ceramic article, and wherein repeating the heat treating in the presence of oxygen dry cleans the ceramic article by causing said polymers to react with the oxygen to become gases.

12. The method of claim 7 , wherein the heat treating causes a grain size of the ceramic coating to increase, and wherein a duration of the heat treating and the temperature range are selected so that a target grain size is reached.

13. The method of claim 7 , wherein the ceramic coating further comprises at least one of ZrO 2 , Al 2 O 3 , SiO 2 , B 2 O 3 , Er 2 O 3 , Nd 2 O 3 , Nb 2 O 5 , CeO 2 , Sm 2 O 3 or Yb 2 O 3 .

14. The method of claim 7 , wherein:
the heat treating is performed using at least one of laser surface treatment, electron beam surface treatment, flame surface treatment, or plasma treatment; and
the thermal spraying process is a plasma spraying process.

15. A method comprising:
receiving a heat treated ceramic article, wherein the heat treated ceramic article comprises a thermal sprayed ceramic coating, wherein the ceramic coating has been used in a plasma etch process, wherein the ceramic article comprises Al 2 O 3 and the ceramic coating comprises Y 4 Al 2 O 9 and a solid solution of Y 2 O 3 —ZrO 2 , and wherein the ceramic coating has an initial density of surface defects caused by the plasma etch process, the surface detects comprising an initial porosity and an initial amount of cracking;
heating the ceramic article to a temperature range between about 1000° C. and about 1800° C. at a ramping rate of about 0.1° C. per minute to about 20° C. per minute;
heat treating the ceramic article at one or more temperatures within the temperature range for a duration of up to about 24 hours to reduce the surface defect density caused by the plasma etch process, wherein the heat treating is at a temperature below a sintering temperature for the ceramic coating to prevent sintering of the ceramic coating, wherein the heat treating causes the ceramic coating to react with the ceramic substrate to form a transition layer between the ceramic substrate and the ceramic coating, and wherein the duration and the temperature range cause the transition layer to have a thickness of about 1 microns to about 5 microns, wherein the transition layer comprises Y 3 Al 5 O 12 ; and
cooling the ceramic article at the ramping rate after the heat treating, wherein after compl

Assignees

• Applied Materials Inc

Inventors

• Sun Jennifer Y
• Duan Ren-Guan
• Kanungo Biraja P
• Lubomirsky Dmitry

Classifications

• C04B41/89 Primary

  for obtaining at least two superposed coatings having different compositions · CPC title

• C04B41/5045

  Rare-earth oxides · CPC title

• Y10T428/265

  1 mil or less · CPC title

• C04B41/80

  of only ceramics · CPC title

• C04B41/87 Primary

  Ceramics · CPC title