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WO-2026096098-A1 - ERBIUM ALUMINUM PEROVSKITE COMPOSITIONS AND RELATED METHODS AND ARTICLES

WO2026096098A1WO 2026096098 A1WO2026096098 A1WO 2026096098A1WO-2026096098-A1

Abstract

Described are aluminate compositions that contain erbium aluminum oxide as a perovskite crystalline structure; methods of preparing aluminate compositions that contain erbium aluminum perovskite; articles that contain erbium aluminum perovskite, and methods of preparing and methods of using articles that contain erbium aluminum perovskite.

Inventors

  • Walker, Luke
  • STERN, CHRISTIAN

Assignees

  • HERAEUS COVANTICS NORTH AMERICA LLC

Dates

Publication Date
20260507
Application Date
20250916
Priority Date
20241031

Claims (14)

  1. 1. An erbium aluminum oxide composition comprising a phase purity of at least 90 weight percent erbium aluminum perovskite.
  2. 2. The composition of claim 1, in the form of a sintered body.
  3. 3. The composition of claim 2, where the sintered body has a porosity in a range from 0.01 to 10 percent.
  4. 4. The composition of claim 1, where the composition comprises impurities of no more than 250 ppm.
  5. 5. The composition of claim 1 in the form of a powder that comprises particles that comprise at least 90 weight percent erbium aluminum perovskite.
  6. 6. The composition of claim 1 in the form of a coating.
  7. 7. The composition of claim 1, having a resistance to plasma etching that is greater than a resistance to plasma etching of yttrium aluminum garnet.
  8. 8. A plasma chamber comprising an interior and a composition of claim 7 within the interior as a plasma-facing surface.
  9. 9. A method of preparing an erbium aluminum oxide composition comprising at least 90 weight percent erbium aluminum perovskite, the method comprising: preparing a powder mixture comprising erbium oxide particles and aluminum oxide particles, and heating the powder mixture, without melting the particles, to cause the erbium oxide and aluminum oxide of the powder mixture to react to form erbium aluminum perovskite.
  10. 10. The method of claim 9, wherein the powder mixture is prepared by attrition milling the powder mixture for at least 2 hours.
  11. 11. The method of claim 10, comprising heating the powder mixture at approximately atmospheric pressure or below to form a powder comprising particles that comprise a phase purity at least 90 weight percent erbium aluminum perovskite.
  12. 12. The method of claim 10, comprising: placing the powder mixture in a die interior, removing gaseous oxygen from the die interior, applying unilateral pressure to the powder mixture in the die, and increasing a temperature of the powder mixture to cause erbium oxide and aluminum oxide of the powder mixture to react to form erbium aluminum perovskite, and to cause the particles to fuse together without melting to form a sintered body that comprises at least 90 weight percent erbium aluminum perovskite.
  13. 13. The method of claim 12, wherein the pressure does not exceed 50 MPa, and the temperature does not exceed 1700 degrees Celsius.
  14. 14. A method of forming a coating on a substrate surface, the coating comprising at least 90 weight percent erbium aluminum perovskite, the method comprising: providing a powder comprising particles that comprise a phase purity of at least 90 weight percent aluminum perovskite, forming an aerosol that contains the particles, and under vacuum conditions, directing the aerosol toward a surface of a substrate such that the particles contact the surface and remain at the surface as a coating that comprises at least 90 weight percent erbium aluminum perovskite.

Description

ERBIUM ALUMINUM PEROVSKITE COMPOSITIONS AND RELATED METHODS AND ARTICLES FIELD [1] The description relates to compositions that contain erbium aluminum oxide as a perovskite crystalline structure (or “crystalline phase”); methods of preparing compositions that contain erbium aluminum perovskite; articles that contain erbium aluminum perovskite; sintered bodies that comprises erbium aluminum perovskite; and methods of preparing and methods of using compositions and articles that contain erbium aluminum perovskite. BACKGROUND [2] Ceramics, meaning room-temperature solid inorganic non-metallic materials, are known to exist as having different chemical compositions that may have a range of different crystalline and non-crystalline (amorphous) morphologies. Among known ceramic materials, one class that includes a large number of chemically-diverse varieties is aluminates, which are composed of aluminum, oxygen, and metal atoms. Aluminates encompass materials with a large range of chemical compositions, many of which are capable of existing in multiple different crystalline phases. Within aluminates that contain the same metal element, a slightly different stoichiometry or crystalline makeup can produce significantly different mechanical, optical, and chemical properties, allowing for different uses of slightly different versions of aluminates. [3] As just one example out of many known aluminates, aluminates that contain yttrium can form ceramics that have a range of highly distinctive and specialized optical, chemical, and mechanical properties. Highly pure yttrium aluminum oxide in a cubic crystalline form, often referred to as a garnet (YAG), for example, has well-known chemical inertness and is used as a chemically-resistant material in the presence of plasma and halogens, e.g., as a coating within plasma chambers. YAG having the cubic crystalline structure can also be doped with another rare earth metal atoms for use in a solid-state laser such as Nd: YAG. Yttrium aluminum oxide exists in various different crystalline forms that include distorted cubic crystalline structure, such as an orthorhombic crystalline structure, a perovskite structure (YAP), and a monoclinic crystalline structure (YAM). [4] One type of ceramic that has not been the subject of study is erbium aluminate (“erbium aluminum oxide”). This aluminate may exhibit multiple different crystalline forms (or “phases”) depending on the composition including as the erbium aluminum garnet phase EnAlsO (“ErAG”), as the erbium aluminum monoclinic phase Er4ATO9 (“ErAM”), or as the erbium aluminum perovskite phase ErAlCh (“ErAP”). [5] The unique chemistry of the rare earth (Lanthanide) aluminates gives them a high resistance to fluorine-based chemistry, particularly as a plasma, commonly used for semiconductor processing in etch chambers. In the semiconductor manufacturing industry, processing equipment such as plasma etching chambers and plasma deposition chambers (referred to collectively as “plasma chambers”) contain a highly pure environment that is as free as possible from particle contaminants. Interior surfaces and components of plasma chambers are made of inert materials that are resistant to chemical degradation because chemical degradation of those materials within a plasma chamber will produce particle contaminants in the chamber. Reducing the reaction of the chamber materials with the plasma environment through the use of ceramic components is an area of high interest to improve yield and up-time that are impacted be degrading chamber materials. [6] US 2022/234959 Al describes nanoparticles having a thin film coating, whereby the thin film coating may be composed of different materials such as erbium aluminum oxide. However, the prior art reference neither discloses the structure of the erbium aluminum oxide nor that the material has a specific phase purity. A thin film coating is prepared by atomic layer deposition which may lead to specific crystalline forms. US 10730798 B refers to a ceramic coating which may be formed on a substrate using slurry plasma spray deposition. Thereby, the coating may comprise ErA103. SUMMARY [7] While many ceramic materials have good resistance to chemical degradation and controlled erosion effects in the presence of reactive chemicals and plasmas, ongoing interest exists for still-better-performing materials, e.g., ceramic materials with still better chemical inertness that produce ever-lower amounts of particle contamination when used at an interior of a plasma chamber. Due to the complex nature of the semiconductor manufacturing process a wide range of plasma chemistries and process conditions are present requiring a range of material solutions to achieve the best performance. [8] Described herein are a novel erbium aluminate composition that contain predominately erbium aluminum perovskite. A crystalline perovskite phase is considered to have a stoichiometry described by the formula ABX3, including whe