Zone-controlled rare-earth oxide ald and CVD coatings

Abstract

To provide an article including a rare-earth coating having one or more brockage layers for controlling a crystal growth.SOLUTION: An article including a protective coating with a plasma resistance on a surface thereof. The protective coating with the plasma resistance is a stack of layers in which a crystalline rare earth oxide layer and a crystalline or amorphous metal oxide layer are laminated alternatively. A first layer of the stack alternatively laminated is the crystalline rare earth oxide layer. The crystalline rare earth oxide layer has a thickness of about 500 to 5,000 Angstrom. If the metal oxide layer is crystalline, the metal oxide layer has an atomic crystalline phase different from that of the crystalline rare earth oxide layer. The metal oxide layer has a thickness of about 1 to 500 Angstrom. Either of the crystalline or amorphous metal oxide layer include a stack suppressing a grain growth of the crystalline rare earth oxide layer.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The embodiments disclosed herein generally relate to rare earth coatings having a barrier layer for an article. In particular, it relates to yttrium oxide coatings having one or more barrier layers for controlling the growth of yttrium oxide grains. Background

[0002] In various manufacturing processes, semiconductor processing chamber components are exposed to high temperatures, high energy plasmas, mixtures of corrosive gases, high stresses, and combinations thereof. These extreme conditions can erode and / or corrode the chamber components and increase the sensitivity of the chamber components to defects.

[0003] Protective coatings used to reduce defects in chamber components due to harsh processing conditions are typically deposited on the chamber components. The protective coating can be deposited by various techniques. Examples of such techniques include, but are not limited to, spraying, sputtering, ion assist deposition (IAD), plasma spraying, vapor deposition techniques, atomic layer deposition, chemical vapor deposition, etc. Some of these techniques may produce protective coatings having abnormally large crystal grains. Abnormally large crystal grains can increase the surface roughness of the protective coating and provide a path for chemicals to diffuse through cracks that may occur through the intergranular or grain boundaries.

[0004] In an exemplary embodiment, an article is disclosed herein that includes a plasma-resistant protective coating on a surface of the article. The plasma-resistant protective coating may include a stack of layers in which a crystalline rare earth oxide layer and a crystalline or amorphous metal oxide layer overlap alternately. The first layer of the stack of alternately overlapping layers may be a crystalline rare earth oxide layer. The crystalline rare earth oxide layer may have a thickness of about 500 to 5000 angstroms. In embodiments where the metal oxide layer is crystalline, each metal oxide layer may have an atomic crystal phase different from the crystal phase of the rare earth oxide layer. Each metal oxide layer may have a thickness of about 1 to 500 angstroms. The crystalline or amorphous metal oxide layer may suppress grain growth within the crystalline yttrium oxide layer.

[0005] In an exemplary embodiment, a method is disclosed herein that includes a step of depositing a plasma-resistant protective coating on a surface of an article. In this step, atomic layer deposition (ALD) processing or chemical vapor deposition (CVD) processing is used. The step of depositing the plasma-resistant protective coating may include a step of depositing a crystalline rare earth oxide layer using ALD or CVD. The step of depositing the plasma-resistant protective coating may further include a step of depositing a crystalline or amorphous metal oxide layer on the crystalline rare earth oxide layer using ALD or CVD. In embodiments where the metal oxide layer is crystalline, the metal oxide layer may have an atomic crystal phase different from the crystal phase of the crystalline rare earth oxide.

[0006] In an exemplary embodiment, a method is disclosed herein that includes depositing a plasma-resistant protective coating on a surface of an article. In this process, atomic layer deposition (ALD) or chemical vapor deposition (CVD) processes are used. The process of depositing the plasma-resistant protective coating may include depositing a stack of layers in which crystalline yttrium oxide layers and crystalline or amorphous metal oxide layers overlap alternately. Each of the crystalline yttrium oxide layers may have a cubic phase and a thickness of about 500 to 5000 angstroms. In embodiments where the metal oxide layer is crystalline, the metal oxide layer may have an atomic crystal phase different from the cubic phase of crystalline yttrium oxide. Each metal oxide layer may have a thickness of about 1 to 500 angstroms. The first layer of the stack of alternately overlapping layers may be a crystalline yttrium oxide layer. The crystalline or amorphous metal oxide layer may suppress grain growth within the crystalline yttrium oxide layer.

Brief Description of the Drawings

[0007] Embodiments of the present invention are shown in the figures of the accompanying drawings by way of example and not limitation, and in these drawings, like reference numerals indicate like elements. It should be noted that different references to "one" or "an" embodiment in this disclosure are not necessarily references to the same embodiment, and such references mean at least one.

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[0008] The embodiments described herein encompass articles (e.g., coated chamber components) and methods, where a plasma-resistant protective coating having one or more (poly)crystalline single-phase or multiphase rare-earth oxide layers and one or more amorphous or (poly)crystalline single-phase or multiphase barrier layers is deposited on the surface of the article. In an exemplary embodiment, one or more crystalline rare-earth oxide layers may include crystalline yttrium oxide in a cubic phase. As an example, the embodiments herein are described using a crystalline yttrium oxide layer in a cubic phase. It will be understood that the layers between the barrier layers may include any rare-earth metal oxide or a mixture of (poly)crystalline single-phase or multiphase rare-earth metal oxides (i.e., with or without yttrium). For example, the rare-earth metal oxide layer between the barrier layers may include yttrium oxide and / or yttrium zirconium oxide.

[0009] In an exemplary embodiment, one or more amorphous or (poly)crystalline single-phase or multiphase barrier layers may include a crystalline or amorphous metal oxide layer selected from the group consisting of rare-earth metal-containing oxides, zirconium oxide, aluminum oxide, and mixtures thereof. In embodiments where one or more barrier layers are (poly)crystalline single-phase or multiphase, the barrier layer may have one atomic crystal phase or multiple atomic crystal phases different from the cubic phase of crystalline yttrium oxide. For example, the (poly)crystalline single-phase or multiphase of the barrier layer may be selected from the group consisting of a hexagonal phase, a monoclinic phase, a cubic phase (when the rare-earth oxide layer is cubic yttrium oxide, the barrier layer may have a lattice structure different from the lattice structure of the cubic phase of crystalline yttrium oxide), a hexagonal phase, a tetragonal phase, and combinations thereof.

[0010] As used herein, the term "plasma-resistant" means resistance to one or more plasmas as well as resistance to chemical properties and radicals associated with one or more plasmas.

[0011] As used herein, the terms "polycrystalline" and "crystalline" are used interchangeably herein and may mean a material comprising many crystallites (also called crystallites). Here, these crystallites are randomly oriented with respect to each other, or have a preferred orientation or preferred texture, and may still have various sizes. The regions where the crystallites contact are called grain boundaries. The polycrystalline layer may include a single crystal phase or a plurality of crystal phases (also referred to as "multiphase" in the technical terms herein). When referring to a multiphase layer herein, it is understood to refer to a crystal layer or a polycrystalline layer having a plurality of crystal phases.

[0012] The surface of the article may be a metallic material (e.g., aluminum (e.g., Al6061, Al6063) and stainless steel, etc.) or a ceramic material (e.g., alumina (Al 2 O 3 ), etc.).

[0013] The deposition process may be an atomic layer deposition (ALD) process or a chemical vapor deposition (CVD) process. Using ALD and CVD processes, one or more crystalline rare earth oxide layers and one or more amorphous or crystalline metal oxide barrier layers may be deposited. A layer containing a plurality of metals may be deposited by sequential deposition of precursors or co-deposition of precursors.

[0014] The plasma-resistant protective coating may be composed of a two-layer stack or a stack of a plurality of alternately overlapping layers. The two-layer stack or the stack of a plurality of alternately overlapping layers may include, for example, one or more layers of cubic-phase crystalline single-phase yttrium oxide (Y 2 O 3 ), and one or more layers of, for example, tetragonal-phase and monoclinic-phase multiphase zirconium oxide layers. The two-layer stack or the stack of a plurality of alternately overlapping layers may include, for example, one or more layers of cubic-phase crystalline single-phase yttrium oxide (Y 2 O 3One or more layers of ) and one or more layers of, for example, a crystalline single-phase zirconium yttrium oxide layer in a tetragonal phase may be included. A two-layer stack or a stack of a plurality of alternately overlapping layers may be, for example, one or more layers of a crystalline single-phase yttrium oxide (Y 2 O 3 ) in a cubic phase of a first lattice structure, and one or more layers of, for example, a cubic-phase zirconium yttrium oxide layer having a second lattice structure and one or more layers of a multiphase mixture of, for example, yttrium oxide in a cubic phase having a third lattice structure. The second lattice structure and the third lattice structure are different from the first lattice structure.

[0015] The thickness of each barrier layer in the multilayer plasma-resistant protective coating may range from about 1 angstrom to about 500 angstroms. The thickness of each rare earth oxide layer in the multilayer plasma-resistant protective coating may range from about 500 angstroms to about 10,000 angstroms. In some embodiments, the thickness of each rare earth oxide layer in the multilayer plasma-resistant protective coating may range from about 500 angstroms to about 5,000 angstroms. In various embodiments, the multilayer plasma-resistant protective coating may have a thickness of from about 1 μm to about 10 μm, or from about 1 μm to about 5 μm. The plasma-resistant protective coating can coat or cover the surface of features of an article having a high aspect ratio, for example, from about 10:1 to about 300:1. The plasma-resistant protective coating can also conformally cover such features with a substantially uniform thickness. In one embodiment, the plasma-resistant protective coating conformally covers the underlying surface (including the surface features to be coated) with a uniform thickness. This uniform thickness has a thickness variation of less than about ±20%, ±10%, ±5%, or less from one part of the coating to another part of the coating. The plasma-resistant protective coating is also very dense and has a porosity of about 0% (for example, in various embodiments, the plasma-resistant protective coating may be pore-free).

[0016] ALD enables controlled self-limiting deposition of materials through chemical reactions with the surface of an article. Aside from being a conformal process, ALD is also a uniform process. The same or nearly the same amount of material is deposited on all exposed surfaces of an article that includes features with a high aspect ratio (e.g., from about 10:1 to about 300:1). A typical reaction cycle for ALD processing begins with a precursor (i.e., a single chemical substance A) that flows into the ALD chamber and adsorbs onto the surface of the article. Subsequently, the excess precursor is evacuated from the ALD chamber, after which a reactant (i.e., a single chemical substance R) is introduced into the ALD chamber and then evacuated. However, a metal oxide blocking layer may be formed by co-deposition of materials. To achieve this, a mixture of two precursors, such as a first metal-containing oxide precursor (A) and a second metal-containing oxide precursor (B), may be co-injected into the chamber at any number (AxBy) of ratios, e.g., A90+B10, A70+B30, A50+B50, A30+B70, A10+A90, etc., and adsorbed onto the surface of the article. In these examples, x and y are expressed as molar ratios (mol%) as Ax+By. For example, A90+B10 means that A is 90 mol% and B is 10 mol%. Alternatively, the two precursors may be injected sequentially (without injecting a reactant in between). The excess precursor is evacuated. The reactant is introduced into the ALD chamber and reacts with the adsorbed precursor to form a solid layer, after which the excess chemical is evacuated. In the case of ALD, the final thickness of the material depends on the number of reaction cycles performed. This is because in each reaction cycle, a layer of a specific thickness of one atomic layer or a fraction of one atomic layer grows.

[0017] CVD enables the deposition of high-density, high-purity, and uniform coatings, which have good reproducibility and adhesion at high deposition rates. A typical reaction cycle of CVD may include the steps of generating a precursor from starting materials, transporting the precursor to a reaction chamber, adsorbing the precursor onto a heated article, chemically reacting the precursor with the surface of the article to be coated to form a deposit and gaseous by-products, and removing the gaseous by-products and unreacted gaseous precursors from the reaction chamber. However, a metal oxide blocking layer may be formed by co-deposition of materials. To achieve this, a mixture of two precursors (such as a first metal-containing oxide precursor (A) and a second metal-containing oxide precursor (B)) may be co-injected into the chamber in any number (AxBy) ratio, similar to ALD technology, and deposited on the surface of the article.

[0018] Unlike other techniques commonly used to deposit coatings on components having high aspect ratio features (such as plasma spraying and ion assist deposition), ALD and CVD techniques can deposit a layer of material within such features (i.e., on the surface of the features). Further, ALD and CVD techniques produce relatively thin (e.g., 10 μm or less) coatings that are pore-free (i.e., pinhole-free), so crack formation during deposition can be eliminated. As used herein, the term "pore-free" means that there are no holes, pinholes, voids, or cracks as measured by transmission electron microscopy (TEM) along the entire depth of the coating. TEM can be performed while operating at 200 kV in bright field, dark field, and high-resolution modes using 100 nm thick TEM lamellas created by focused ion beam milling. In contrast, in conventional electron beam IAD or plasma spraying techniques, cracks can occur during deposition even at a thickness of 5 or 10 μm, and the porosity can be 1 - 3% or more.

[0019] A plasma-resistant protective coating can be deposited on various articles. In some embodiments, processing chamber components such as electrostatic chucks, nozzles, gas distribution plates, showerheads, electrostatic chuck components, chamber walls, liners, liner kits, gas lines, lids, chamber lids, nozzles, single rings, process kit rings, bases, shields, plasma screens, flow equalizers, cooling bases, chamber viewports, bellows, faceplates, selectivity modulators, plasma generation units (e.g., radio frequency electrodes having a housing), and diffusers benefit from having these plasma-resistant protective coatings that protect the components in the harsh environment of corrosive plasmas. Many of these chamber components have high aspect ratios in the range of about 10:1 to about 300:1 and other complex shapes, so it is difficult to coat them properly with conventional deposition methods. The embodiments described herein enable coating high aspect ratio articles such as the aforementioned processing chamber components with a plasma-resistant protective coating that protects the article.

[0020] Examples of process gases that can be used to process a substrate in a processing chamber include, among others, C 2 F 6 , SF 6 , SiCl 4 , HBr, NF 3 , CF 4 , CHF 3 , CH 2 F 3 , F, NF 3 , Cl 2 , CCl 4 , BCl 3 , SiF 4 and other halogen-containing gases such as, and O 2 or N 2 O and other gases. Examples of carrier gases include N 2 , He, Ar, and other gases that are inert to the process gas (e.g., non-reactive gases).

[0021] FIG. 1A shows one embodiment of a deposition process 100 by ALD technology for growing or depositing a plasma-resistant protective coating on an article. FIG. 1B shows another embodiment of a deposition process 102 by the ALD technology described herein. FIG. 1C shows yet another embodiment of a deposition process 104 by the ALD deposition technology described herein. There are various types of ALD processing methods, and the specific type can be selected based on several factors such as the surface to be coated, the coating material, and the chemical interaction between the surface and the coating material. The general principle of various ALD processing methods includes a step of growing a thin film layer by repeatedly exposing the surface to be coated to pulses of gaseous chemical precursors. Here, the precursor reacts chemically with the surface one by one in a self-limiting manner.

[0022] FIGS. 1A-1C show an article 110 having a surface. The article 110 may represent various processing chamber components (e.g., semiconductor processing chamber components). Such components include, but are not limited to, an electrostatic chuck, a nozzle, a gas distribution plate, a showerhead, an electrostatic chuck component, a chamber wall, a liner, a liner kit, a gas line, a lid, a chamber lid, a nozzle, a single ring, a process kit ring, a base, a shield, a plasma screen, a flow equalizer, a cooling base, a chamber viewport, a bellows, a faceplate, a selectivity modulator, etc. The article 110 (and the article 230 in FIG. 2) may be made of metal (such as aluminum, stainless steel, etc.), ceramic (e.g., Y 2 O 3 、Al 2 O 3 、Y 3 Al 5 O 12 (YAG), etc.), a metal-ceramic composite, a polymer, a polymer-ceramic composite, a mylar, a polyester, or other suitable materials, and may further include materials such as AlN, Si, SiC, Al 2 O 3 、SiO 2 、 etc.

[0023] In the case of ALD, either the adsorption of the precursor onto the surface or the reaction of the reactant with the adsorbed precursor will be referred to as a "half - reaction". During the first half - reaction, for a sufficient time for the precursor to be fully adsorbed onto the surface, the precursor is rhythmically fed onto the surface of article 110 (or onto a layer formed on article 110). Since the precursor adsorbs onto a finite number of available sites on the surface and forms a uniform continuous adsorption layer on the surface, the adsorption is self - limiting. The sites that have already adsorbed the precursor are not available for further adsorption of the same precursor unless and until the adsorbed sites undergo a treatment where the adsorbed sites form new available sites on a uniform continuous coating. Exemplary treatments may be plasma treatment, i.e., a treatment that exposes the uniform continuous adsorption layer to radicals, or the introduction of another precursor that can react with the latest uniform continuous layer adsorbed on the surface.

[0024] In some embodiments, two or more precursors are injected together and adsorbed onto the surface of the article. After the excess precursors are discharged, eventually an oxygen - containing reactant is injected to react with the adsorbed substances to form a single metal oxide layer or a multi - metal oxide layer (e.g., such as the phase of YAG and Y 2 O 3 -ZrO 2 ). This new layer can adsorb the precursor in the next cycle.

[0025] In FIG. 1A, article 110 is directed to a first precursor 160 during a first period, and eventually the surface of article 110 may fully adsorb the first precursor 160 to form an adsorption layer 114. Subsequently, article 110 is directed to a first reactant 165 to react with the adsorption layer 114 to grow a rare - earth oxide layer 116. (For example, to fully grow or deposit the rare - earth oxide layer 116. In this specification, the terms "grow" and "deposit" may be used interchangeably.) The first precursor 160 may be, for example, a precursor for yttrium or other metals. The first reactant 165 may be oxygen, water vapor, ozone, pure oxygen, oxygen radicals, or other oxygen sources if the rare - earth layer 116 is an oxide. Thus, a rare - earth oxide layer 116 may be formed using ALD.

[0026] In the example where the rare earth oxide layer 116 is a yttria (Y 2 O 3 ) rare earth oxide layer, the article 110 (e.g., an Al6061 substrate with or without an alumina buffer layer) may be introduced to the first precursor 160 (e.g., tris(methylcyclopentadienyl)yttrium) during the first period, and eventually all reaction sites on the surface may be consumed. The remaining first precursor 160 is exhausted, and then, the first reactant 165 which is H 2 O is injected into the reactor to start the latter half of the cycle. After the H 2 O molecules react with the Y-containing adsorption layer generated by the first half-reaction, a rare earth oxide layer 116 of Y 2 O 3 is formed.

[0027] The rare earth oxide layer 116 may be a uniform, continuous, and conformal layer. The rare earth oxide layer 116 may be pore-free (e.g., porosity 0), or in some embodiments may have a substantially zero porosity (e.g., porosity 0% to 0.01%). In some embodiments, after a single ALD deposition cycle, the layer 116 may have a thickness ranging from less than one atomic layer to several atoms. Some organometallic precursor molecules are large.

[0028] Multiple complete ALD deposition cycles may be performed to deposit a thicker rare earth oxide layer 116. In each complete cycle (e.g., including the steps of introducing the precursor 160, exhausting, introducing the reactant 165, and exhausting again), the thickness increases by a fraction of an atom to several atoms. As shown in the figure, up to n complete cycles may be executed to grow the rare earth oxide layer 116. Here, n is an integer value greater than 1. In some embodiments, the rare earth oxide layer 116 may have a thickness of about 500 angstroms to about 10,000 angstroms, about 500 angstroms to about 5,000 angstroms, about 1,000 angstroms to about 5,000 angstroms, or about 1,500 angstroms to about 2,500 angstroms.

[0029] Since ALD can be used for deposition, the inner surfaces of high aspect ratio features such as showerhead or gas supply holes in the gas supply line may be coated, and thus the entire component can be protected from exposure to a corrosive environment.

[0030] In various embodiments, layer 116 is crystalline Y having a single cubic phase 2 O 3 such as Y 2 O 3 may be. In one embodiment, the cubic phase of yttrium oxide may exhibit an X-ray diffraction curve corresponding to powder diffraction file number 04-005-4378.

[0031] It should be understood that in some embodiments, layer 116 may include two or more rare earth metals. Deposition of a multi-element rare earth oxide layer by ALD may be performed by sequential deposition as described for the metal oxide layer of FIG. 1B, or by co-deposition as described in more detail with respect to FIG. 1C.

[0032] Subsequently, the article 110 having the layer 116 is directed to a further precursor 170 during a second period, and eventually the surface of the rare earth oxide layer 118 completely adsorbs the further precursor 170 to form an adsorption layer 118. Subsequently, the article 110 is directed to a reactant 175 and reacts with the adsorption layer 118 to grow an amorphous or crystalline single-phase or polyphase metal oxide layer 120 (e.g., such that the blocking layer 120 is completely grown or deposited). This metal oxide layer 120 is also simply referred to as the blocking layer 120. Thus, the blocking layer 120 is completely grown or deposited on the rare earth oxide layer 116 using ALD. In one example, the precursor 170 may be a zirconium-containing precursor (e.g., tris(dimethylamino)cyclopentadienylzirconium) used in the first half of the cycle, and the reactant 175 may be ozone used in the second half of the cycle.

[0033] The barrier layer 120 forms an amorphous or crystalline single-phase or multi-phase metal oxide layer, and this metal oxide layer may be a uniform and continuous conformal layer. The second layer 120 may have a very low porosity, less than 1% in some embodiments, less than 0.1% in further embodiments, and about 0% in some embodiments, and no pores in still further embodiments. The second layer 120 may have a thickness of from 1 atom to several atoms (e.g., 2 - 3 atoms) after one complete ALD deposition cycle. Multiple ALD deposition steps can be carried out to deposit a thicker barrier layer 120, and in each step, the thickness increases by a fraction of 1 atom to several atoms. As shown in the figure, the complete deposition cycle may be repeated m times so that the barrier layer 120 has a target thickness. Here, m is an integer value greater than 1. In some embodiments, the barrier layer 120 may have a thickness of from about 1 angstrom to about 500 angstroms, from about 2 angstroms to about 200 angstroms, or from about 3 angstroms to about 50 angstroms.

[0034] The ratio of the thickness of the rare earth oxide layer to the thickness of the barrier layer may be from about 5000:1 to about 1:1, or about 2500:1. In some embodiments, the ratio of the thickness of the rare earth oxide layer to the thickness of the barrier layer may be from about 500:1 to about 1:1. In still other embodiments, the ratio of the thickness of the rare earth oxide layer to the thickness of the barrier layer may be about 2500:8, about 2500:12, or about 2500:16. The ratio of the rare earth oxide layer to the barrier layer can be a value that improves the corrosion resistance and erosion resistance of the protective coating and the resistance to cracks and / or delamination caused by chamber processing. The thickness ratio may be selected according to a specific chamber application.

[0035] As shown in FIGS. 4A and 4B, an yttrium oxide layer deposited without a barrier layer results in uncontrollable and abnormally large grain growth. For example, the abnormally large yttrium oxide grains shown in FIGS. 4A and 4B can have a height of about 100 nm and a width of about 200 nm. These abnormally large grains result in a larger surface roughness and make the coating more prone to defects. This phenomenon is evident in a 600 nm thick yttrium oxide coating and will be even more pronounced in thicker yttrium oxide coatings (see, for example, FIG. 14A for grains in a 1 μm thick yttria coating without a barrier layer). Further, the absence of a barrier layer provides a direct path for chemicals to diffuse through cracks and gaps between the large grains and reach the interface between the coating and the article. Thus, there is a possibility of damaging the coated article.

[0036] FIG. 4C shows a barrier layer between the yttrium oxide layers (i.e., a carbon-rich yttrium oxide barrier layer was deposited after each 250 nm thick yttrium oxide layer). Indeed, the growth of the yttrium oxide grains is suppressed, and the surface boundaries and surface roughness are also suppressed. None of the grains in FIG. 4C exceed 100 nm in length or 200 nm in width. Further, there is no direct path from the corrosive chamber environment through the coating and ultimately to the interface between the coating and the article. However, due to the high carbon content in the barrier layer, the layer is relatively weak. As a result, when compressive stress acts on the protective coating during processing, as shown in FIG. 4C, the top yttrium oxide layer buckles and begins to flake. Such delamination generates particles and affects the life of the coated article, the life of the coating, and wafer processing. Compressive stress acts after fluorination when the crystal lattice of the protective coating begins to expand.

[0037] When the barrier layer is stronger than the carbon barrier layer, the yttrium oxide layer and the barrier layer remain connected and do not buckle. A stronger barrier layer is considered to have a composition similar to that of the yttrium oxide layer, but different from the yttrium oxide layer, and to have an atomic crystal phase that will suppress uncontrollable grain growth. Therefore, the determination regarding the type of metal oxide layer selected for the barrier layer, the type of rare earth oxide layer selected, and their corresponding thicknesses should take into account the need to control the grain growth of the rare earth oxide. On the other hand, these determinations ensure a sufficiently strong bond between the rare earth oxide layer and the barrier layer, preventing delamination and particle generation between the layers.

[0038] The barrier layer 120 may be any of the aforementioned rare earth metal-containing oxide layers, as well as zirconium oxide, aluminum oxide, and mixtures thereof. For example, the barrier layer 120 may be ZrO 2 alone, or ZrO 2 in combination with one or more other rare earth metal oxides. In some embodiments, the barrier layer 120 is a crystalline single-phase or polyphase material having one or more atomic crystal phases, and this material is formed from a single metal oxide or a mixture of at least two metal oxide precursors sequentially deposited or co-deposited by ALD. For example, the barrier layer 120 may be La 2 O 3 , Pr 2 O 3 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , Tb 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , ZrO 2and can be one of those combinations (as shown in FIG. 3). In certain embodiments, the blocking layer may be amorphous. In embodiments where the blocking layer is crystalline, one or more crystalline atomic phases of the blocking layer may be different from one or more crystalline atomic phases of the rare earth oxide layer. In embodiments where at least one crystalline atomic phase of the blocking layer is the same as at least one crystalline atomic phase of the rare earth oxide layer, the lattice structures of the similar crystalline atomic phases may be different. For example, the atomic crystalline phase can be selected from the group consisting of hexagonal, tetragonal, cubic, monoclinic, and combinations thereof.

[0039] In some embodiments, the first layer 116 and the second layer 120 each comprise Y 2 O 3 and Y 2 O 3 -based ceramics, Y 3 Al 5 O 12 (YAG), Al 2 O 3 (alumina), Y 4 Al 2 O 9 (YAM), ErAlO 3 , GdAlO 3 , NdAlO 3 , YAlO 3 , TiO 2 (titania), ZrO 2 (zirconia), Y 2 O 3 -stabilized ZrO 2 (YSZ), Er 2 O 3 and Er 2 O 3 -based ceramics, Gd 2 O 3 and Gd 2 O 3 -based ceramics, Er 3 Al 5 O 12 (EAG), Gd 3 Al 5 O 12 (GAG), Nd 2 O 3 and Nd 2 O 3Ceramic, Y 2 O 3 and YF 3 A ceramic compound containing (e.g., Y - O - F), Y 4 Al 2 O 9 and Y 2 O 3 -ZrO 2 A ceramic compound containing a solid solution of, Y 2 O 3 , Er 2 O 3 , ZrO 2 , Gd 2 O 3 and SiO 2 It may contain materials such as a ceramic compound containing, or any combination of the above.

[0040] The materials of the first layer 116 and the second layer 120 may also be based on a solid solution formed by any of the aforementioned ceramics. The material may also be a multiphase material containing a solid solution of one or more of the aforementioned materials and one or more additional phases.

[0041] Y 2 O 3 -ZrO 2 Regarding the solid solution of, the material may contain Y at a concentration of 10 - 90 molar ratio (mol%) 2 O 3 and ZrO at a concentration of 10 - 90 mol%. In some examples, Y 2 O 2 O 3 -ZrO 2 The solid solution of may contain 10 - 20 mol% of Y 2 O 3 and 80 - 90 mol% of ZrO 2 It may contain 20 - 30 mol% of Y 2 O 3 and 70 - 80 mol% of ZrO 2 It may contain 30 - 40 mol% of Y 2 O 3 and 60 - 70 mol% of ZrO 2 It may contain 40 - 50 mol% of Y 2 O 3 and 50 - 60 mol% of ZrO2 may contain 60 - 70 mol% of Y 2 O 3 and 30 - 40 mol% of ZrO 2 may contain 70 - 80 mol% of Y 2 O 3 and 20 - 30 mol% of ZrO 2 may contain 80 - 90 mol% of Y 2 O 3 and 10 - 20 mol% of ZrO 2 etc. may be included.

[0042] Y 4 Al 2 O 9 and Y 2 O 3 -ZrO 2 Regarding the ceramic compound containing a solid solution of, in one embodiment, the ceramic compound is 62.93 molar ratio (mol%) of Y 2 O 3 , 23.23 mol% of ZrO 2 and 13.94 mol% of Al 2 O 3 contains. In another embodiment, the ceramic compound is Y in the range of 50 - 75 mol% 2 O 3 , ZrO in the range of 10 - 30 mol% 2 and Al in the range of 10 - 30 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 40 - 100 mol% 2 O 3 , ZrO in the range of 0.1 - 60 mol% 2 and Al in the range of 0.1 - 10 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 40 - 60 mol% 2 O 3 , ZrO in the range of 35 - 50 mol% 2 and Al in the range of 10 - 20 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 40 - 50 mol% 2 O3 、ZrO in the range of 20 to 40 mol% 2 and Al in the range of 20 to 40 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 80 to 90 mol% 2 O 3 、ZrO in the range of 0.1 to 20 mol% 2 and Al in the range of 10 to 20 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 60 to 80 mol% 2 O 3 、ZrO in the range of 0.1 to 10 mol% 2 and Al in the range of 20 to 40 mol% 2 O 3 may be included. In another embodiment, the ceramic compound is Y in the range of 40 to 60 mol% 2 O 3 、ZrO in the range of 0.1 to 20 mol% 2 and Al in the range of 30 to 40 mol% 2 O 3 may be included. In other embodiments, other distributions may be used for the ceramic compound.

[0043] In one embodiment, the material comprises or consists of a ceramic compound containing a combination of Y 2 O 3 、ZrO 2 、Er 2 O 3 、Gd 2 O 3 and SiO 2 . In one embodiment, the ceramic compound is Y in the range of 40 to 45 mol% 2 O 3 、ZrO in the range of 0 to 10 mol% 2 、Er in the range of 35 to 40 mol% 2 O 3 、Gd in the range of 5 to 10 mol% 2 O 3 and SiO in the range of 5 to 15 mol% 2 may be included. In the first example, the alternative ceramic compound is 40 mol% of Y2 O 3 and 5 mol% of ZrO 2 and 35 mol% of Er 2 O 3 and 5 mol% of Gd 2 O 3 and 15 mol% of SiO 2 In the second embodiment, the alternative ceramic compound is 45 mol% of Y 2 O 3 and 5 mol% of ZrO 2 and 35 mol% of Er 2 O 3 and 10 mol% of Gd 2 O 3 and 5 mol% of SiO 2 In the third embodiment, the alternative ceramic compound is 40 mol% of Y 2 O 3 and 5 mol% of ZrO 2 and 40 mol% of Er 2 O 3 and 7 mol% of Gd 2 O 3 and 8 mol% of SiO 2 including.

[0044] Any of the foregoing materials may also contain other materials, such as 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 , Yb 2 O 3 , or other oxides, even in trace amounts. The plasma resistance of the ceramic material and the reduction of contamination on the wafer or substrate by these materials enable a longer working life.

[0045] Referring to FIG. 1B, in some embodiments, the plasma-resistant protective coating includes three or more layers. Specifically, the plasma-resistant protective coating may include a stack of layers in which a rare earth oxide layer and a barrier layer overlap alternately.

[0046] Referring to FIG. 1B, an article 110 having a rare earth oxide layer 116 may be inserted into a deposition chamber. The rare earth oxide layer 116 may be formed as described with reference to FIG. 1A. FIG. 1B shows an ALD process involving sequential deposition for forming a multi-element barrier layer. The article 110 having the rare earth oxide layer 116 may be introduced to one or more precursors 180 for a period of time, and eventually the surface of the rare earth oxide layer 116 completely adsorbs one or more additional precursors 180 to form an adsorption layer 122. Subsequently, the article 110 may be introduced to a reactant 182 to react with the adsorption layer 122 to grow a solid metal oxide layer 124. Thus, the metal oxide layer 124 is completely grown or deposited on the rare earth oxide layer 116 using ALD. In one example, the precursor 180 may be a zirconium-containing precursor used in the first half of the cycle, and the reactant 182 may be H 2 O, which may also be used in the second half of the cycle. The metal oxide layer may be La 2 O 3 , Pr 2 O 3 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , Tb 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , ZrO 2 , Al 2 O 3 or another oxide and combinations thereof.

[0047] An article 110 having a rare earth oxide layer 116 and a metal oxide layer 124 may be introduced to one or more precursors 184 for a period of time, and eventually the surface of the metal oxide layer 124 completely adsorbs one or more precursors 184 to form an adsorption layer 126. The precursor 184 may be different from the precursor 180. Subsequently, the article 110 may be introduced to a reactant 186 to react with the adsorption layer 126 to grow a further solid metal oxide layer 128. Therefore, a further metal oxide layer 128 is completely grown or deposited on the metal oxide layer 124 using ALD. In one embodiment, the precursor 184 may be a yttrium-containing precursor used in the first half of the cycle, and the reactant 186 may be H 2 O used in the second half of the cycle. The metal oxide layer 124 may be La 2 O 3 , Pr 2 O 3 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , Tb 2 O 3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , ZrO 2 , or another oxide and combinations thereof.

[0048] In some embodiments, the metal oxide layer may be crystalline, from at least one pure crystalline single-phase zirconia of tetragonal or monoclinic phase, to a crystalline polyphase or crystalline single-phase yttrium zirconium oxide having an atomic percentage of zirconium of about 5% based on all atoms in the composition, a mixture of about 65 wt% tetragonal zirconium oxide and about 35 wt% monoclinic zirconium oxide, a multi-element oxide of about 100 wt% tetragonal zirconium yttrium oxide, a mixture of about 70 wt% multi-element oxide of a first cubic phase zirconium yttrium oxide and about 30 wt% yttrium oxide of a second cubic phase, wherein the first cubic phase and the second cubic phase have a lattice structure different from the lattice structure of the crystalline yttrium oxide layer, a mixture of about 30 wt% multi-element oxide of a first cubic phase zirconium yttrium oxide and about 70 wt% yttrium oxide of a second cubic phase, and may be selected from the group consisting of.

[0049] As shown, the deposition of the metal oxide 124 and the second metal oxide 128 may be repeated x times to form a stack 137 of alternating layers. Here, x is an integer value greater than 1. X may represent a finite number of layers selected based on the target thickness and characteristics. The stack 137 of alternating layers may be regarded as a blocking layer including a plurality of alternating sub-layers. Therefore, the precursor 180, the reactant 182, the precursor 184, and the reactant 186 may be sequentially and repeatedly introduced to grow or deposit further alternating layers 130, 132, 134, 136, etc. Each of the layers 124, 128, 130, 132, 134, 136, etc. may be a very thin layer having a thickness of less than one atomic layer to several atomic layers.

[0050] The above-described alternating layers 124 to 136 are in a 1:1 ratio. That is, there is a single layer of the first metal oxide for each single layer of the second metal oxide. However, in other embodiments, other ratios such as 2:1, 3:1, 4:1, etc. may exist between various types of metal oxide layers. For example, in one embodiment, Y 2 O 3 Three ZrO per layer2 Layers may be deposited. Further, the stack 137 of alternatingly overlapping layers 124-136 has been described as a series of two alternatingly overlapping metal oxide layers. However, in other embodiments, more than two metal oxide layers may be deposited within the alternatingly overlapping stack 137. For example, the stack 137 may include three different alternatingly overlapping layers (e.g., Y 2 O 3 's first layer, Al 2 O 3 's first layer, ZrO 2 's first layer, Y 2 O 3 's second layer, Al 2 O 3 's second layer, ZrO 2 's second layer, etc.).

[0051] The process of forming the multilayer stack 137 of metal oxide barrier layers is also referred to herein as sequential deposition. When the rare earth oxide layer contains two or more rare earth elements, such sequential deposition may also be used for the rare earth oxide layer.

[0052] After the stack 137 of alternatingly overlapping layers is formed, an annealing treatment may be performed to diffuse the layers of various materials into each other to form a composite oxide having a single crystal phase or a polycrystalline phase. Therefore, after the annealing treatment, the stack of alternatingly overlapping layers 137 may become a single barrier layer 138. For example, if the layers in the stack are Y 2 O 3 , Al 2 O 3 and ZrO 2 , the rare earth metal-containing oxide layer 138 obtained at that time may be a ceramic compound containing a solid solution of Y 4 Al 2 O 9 and Y 2 O 3 -ZrO 2 .

[0053] In some embodiments, the deposition of the rare earth oxide layer 116 and the barrier layer stack 137 (or 138 if annealed) may be repeated z times to form a final plasma-resistant protective coating. The final plasma-resistant protective coating may include layers in which the rare earth oxide layer and the intermittent metal oxide barrier layer overlap alternately.

[0054] Refer to FIG. 1C. An article 110 having a rare earth oxide layer 116 may be inserted into a deposition chamber. The rare earth oxide layer 116 may be formed as described with reference to FIG. 1A. In some embodiments, the article 110 having the rare earth oxide layer 116 may be directed to a plurality of precursors 190A, 190B that may be co-injected or sequentially injected together for a period of time, and finally the surface of the rare earth oxide layer 116 completely adsorbs the plurality of precursors 190A, 190B to form a multi-element adsorption layer 140. Subsequently, the article 110 may be directed to a reactant 192 to react with the adsorption layer 140 to grow a solid multi-element metal oxide layer 142. Thus, the multi-element metal oxide layer 142 is completely grown or deposited on the rare earth oxide layer 116 using ALD. The process of introducing the precursors 190A, 190B and then the reactant 192 may be repeated y times to make the multi-element metal oxide barrier layer 142 reach a target thickness and finally form an amorphous or crystalline single-phase or multi-phase barrier layer. In FIG. 2C, y is an integer greater than 1.

[0055] The process of forming the barrier layer 142 in FIG. 1C is also referred to as co-deposition herein. When the rare earth oxide layer contains two or more rare earth elements, such co-deposition may also be used for the rare earth oxide layer.

[0056] The deposition of the rare earth oxide layer 116 and the barrier layer 142 may be repeated z times to form a stack of alternately overlapping layers that form a final plasma-resistant protective coating. z may be an integer value greater than 1. z may represent a finite number of layers selected based on the target thickness and properties of the final plasma-resistant protective coating.

[0057] The final structures shown in FIGS. 1A - 1B are side cross-sectional views of an article 110 coated with a two-layer plasma-resistant protective coating. This two-layer plasma-resistant protective coating includes a crystalline rare earth oxide layer 116 and an amorphous or crystalline barrier layer 120 (according to FIG. 1A), 137 or 138 (according to FIG. 1B). The final structure shown in FIG. 1C is a side cross-sectional view of an article 110 coated with a multi-layer plasma-resistant protective coating. This multi-layer plasma-resistant protective coating includes a rare earth oxide layer 116 and an amorphous or crystalline barrier layer 142. In some embodiments, the crystalline rare earth oxide layer 116 may be cubic yttrium oxide having a first lattice structure. The crystalline or amorphous barrier layers 120, 137 / 138, or 142 may include rare earth metal oxides, zirconium oxide, aluminum oxide, or mixtures thereof. In embodiments where the barrier layer is crystalline, the barrier layer may have one or more crystal phases different from the crystal phase of the rare earth oxide layer 116.

[0058] The barrier layers 116 and 120, 137 / 138, or 142 may each be selected from the list of materials enumerated above.

[0059] The crystalline rare earth oxide layer 116 may have a thickness ranging from about 500 angstroms to about 5000 angstroms. In embodiments, the rare earth oxide layer may have a thickness ranging from about 1000 - 5000 angstroms. In further embodiments, the rare earth oxide layer 116 may have a thickness ranging from about 1500 - 2500 angstroms.

[0060] The barrier layers 120, 137 / 138, or 142 may have a thickness from about 1 angstrom to about 500 angstroms and may be formed by performing ALD processing for about 1 to 500 cycles. Here, each cycle forms a nanolayer of the barrier layer (or slightly smaller or larger than the nanolayer). In some embodiments, the barrier layers 120, 137 / 138, or 142 may have a thickness from about 2 angstroms to about 200 angstroms. In further embodiments, the barrier layers 120, 137 / 138, or 142 may have a thickness from about 3 angstroms to about 50 angstroms. In one embodiment, each layer of the barrier layer is formed using about 1 to 10 ALD cycles.

[0061] In further embodiments, the plasma-resistant protective coating may have a thickness from about 500 nm to about 5 μm. In further embodiments, the plasma-resistant protective coating may have a thickness from about 1 μm to about 5 μm, or from about 1 μm to about 2 μm. The barrier layers 120, 137, 138, or 142 between the rare earth metal oxide layers 116 may suppress unusually large crystal growth in the rare earth oxide layers to an uncontrollable extent.

[0062] In the embodiments described with reference to FIGS. 1A - 1C, the surface reactions (e.g., half-reactions) may be performed sequentially, i.e., in locations where various precursors and reactants are not in contact. Before introducing a new precursor or reactant, the chamber in which the ALD process is performed may be purged with an inert carrier gas (such as nitrogen or air) to remove any unreacted precursors and / or surface precursor reaction by-products. The precursors may be different for each layer. In some embodiments, the surface reaction may be performed by co-deposition, but only when at least two precursors are used. In some embodiments, at least three precursors are used, and in further embodiments, at least four precursors are used. Before introducing one or more reactants, a plurality of precursors may be co-injected into the ALD chamber. The ALD chamber may be purged with an inert carrier gas (such as nitrogen or air) to remove any unreacted precursors and / or surface precursor reaction by-products.

[0063] ALD processing can be carried out at various temperatures depending on the type of processing. The optimal temperature range for a specific ALD process is called the "ALD temperature window". Temperatures lower than the ALD temperature window may result in low growth rates and non-ALD type depositions. Temperatures exceeding the ALD temperature window may result in reactions caused by chemical vapor deposition (CVD) mechanisms. The ALD temperature window may be in the range of about 100°C to about 400°C. In some embodiments, the ALD temperature window is between about 120 and 300°C.

[0064] ALD processing enables conformal plasma-resistant protective coatings with uniform thickness on articles and surfaces having complex geometries, high aspect ratio holes, and three-dimensional structures. By exposing the surface to each precursor for a sufficient time, the precursor can be dispersed and fully reacted over the entire surface, including all features with their three-dimensional complexity. The exposure time utilized to obtain conformal ALD in high aspect ratio structures is proportional to the square of the aspect ratio and can be predicted using modeling techniques. Furthermore, the ALD technique is more advantageous than other commonly used coating techniques. This is because with this technique, in-situ material synthesis with specific compositions or formulations can be achieved according to requirements, without the need for the production of long and difficult raw materials (such as powder raw materials and sintered targets). In some embodiments, ALD is used to coat articles with an aspect ratio of about 10:1 to about 300:1.

[0065] Using the ALD techniques described herein, multi-component films can be grown, deposited, or co-deposited. As a method, for example, a blocking layer is grown using a mixture of appropriate precursors. This has been described above and will be explained in more detail in the following examples.

[0066] In some embodiments, the plasma-resistant protective coating may be deposited on the surface of an article by CVD. An exemplary CVD system is shown in FIG. 2. This system includes a chemical vapor precursor supply system 205 and a CVD reactor 210. The role of the vapor precursor supply system 205 is to generate a vapor precursor 220 from a starting material 215 that can be in solid, liquid, or gaseous form. The vapor precursor is subsequently transported to the CVD reactor 210 and may be deposited as a plasma-resistant protective coating 225 and / or 245 on the surface of an article 230 disposed on an article holder 235 according to one embodiment.

[0067] The plasma-resistant protective coating shown in FIG. 2 includes two layers: a crystalline single-phase or polyphase rare earth oxide layer 225 and an amorphous or crystalline single-phase or polyphase metal oxide barrier layer 245. Although only two layers are illustrated with respect to the CVD process, it will be understood by those skilled in the art that multilayer plasma-resistant protective coatings are also contemplated herein with respect to the CVD process. Multilayer plasma-resistant protective coatings that include stacks of layers in which (poly)crystalline single-phase or polyphase rare earth oxides and amorphous or (poly)crystalline single-phase or polyphase metal oxide barrier layers deposited by CVD alternate and overlap are considered in certain embodiments herein.

[0068] The CVD reactor 210 heats the article 230 to the deposition temperature using a heater 240. In some embodiments, the heater can heat the walls of the CVD reactor (also known as a "hot wall reactor"), and the walls of the reactor can transfer heat to the article. In other embodiments, only the article can be heated while keeping the walls of the CVD reactor at a low temperature (also known as a "cold wall reactor"). It should be understood that the CVD system configuration should not be construed as limiting. A variety of apparatuses can be utilized for the CVD apparatus, and the apparatus is selected to obtain optimal processing conditions that can provide a coating having a uniform thickness, surface morphology, structure, and composition.

[0069] Various CVD techniques include the following steps: (1) generating reactive gas-phase species (also known as "precursors") from starting materials; (2) transporting the precursors to a reaction chamber (also called a "reactor"); (3) adsorbing the precursors onto a heated article; (4) participating in a chemical reaction between the precursors and the article at the gas-solid interface to form deposits and gaseous by-products; and (5) removing the gaseous by-products and unreacted gaseous precursors from the reaction chamber.

[0070] Suitable CVD precursors are stable at room temperature and may have a low vaporization temperature. Further, suitable CVD precursors produce vapor species that are stable at low temperatures, have an appropriate deposition rate (low deposition rate for thin film coatings and high deposition rate for thick film coatings), are relatively low in toxicity, cost-effective, and may be of relatively high purity. In some CVD reactions, such as pyrolysis reactions (also called "thermal decomposition") and disproportionation reactions, the chemical precursor alone may be sufficient to complete deposition.

[0071] CVD has many advantages, including its ability to deposit high-density, high-purity coatings and its ability to produce uniform films with good reproducibility and adhesion at a moderately high deposition rate. In various embodiments, layers deposited using CVD may have a porosity of less than 1% and a porosity of less than 0.1% (e.g., about 0%). Thus, CVD can be used to uniformly coat components of complex shapes and deposit conformal coatings with a good conformal deposition amount (e.g., with a substantially uniform thickness). CVD may be utilized to deposit films composed of multiple components. For example, this can be achieved by supplying a mixture chamber with multiple chemical precursors in a predetermined ratio and then supplying the mixture to a CVD reactor system.

[0072] Using the CVD and ALD processes described herein, in various embodiments, a plasma-resistant protective coating resistant to erosion and / or corrosion may be formed. The plasma-resistant protective coating deposited by ALD or CVD may include a stack of layers in which a crystalline rare earth oxide layer and an amorphous or crystalline blocking layer alternately overlap. In one embodiment, the plasma-resistant protective coating may be a bilayer of a crystalline rare earth oxide layer and an amorphous or crystalline blocking layer. When the plasma-resistant protective coating includes a stack of alternately overlapping layers, the first layer may be a rare earth oxide layer. The amorphous or crystalline blocking layer may suppress crystal / grain growth within the crystalline rare earth oxide layer, such that the size of the grains within the rare earth oxide layer does not exceed the thickness of the rare earth oxide layer. In some embodiments, the suppression is such that the size of the grains does not exceed 100 nm or 200 nm.

[0073] The rare earth oxide layer may have one or more atomic crystal phases. The blocking layer may have one or more atomic crystal phases different from the atomic crystal phase of the rare earth oxide layer and may suppress the crystal growth of the rare earth oxide crystal. For example, in one embodiment, the rare earth oxide layer may be a cubic phase yttrium oxide layer. In one embodiment, the blocking layer may be a tetragonal phase and monoclinic phase zirconium oxide layer.

[0074] When the rare earth oxide layer or the blocking layer includes a plurality of metal oxides, the materials forming each layer may be sequentially deposited or co-deposited (the ALD process is described in detail through FIGS. 1A - 1C). In some embodiments, a post-coating heat treatment may be performed on the layer containing a plurality of metal oxides. In some embodiments, a post-coating treatment may be performed on each layer of the plasma-resistant protective coating or the final plasma-resistant protective coating to form one or more features therein.

[0075] Exemplary yttrium-containing precursors that can be used with CVD and ALD coating deposition techniques include tris(N,N-bis(trimethylsilyl)amide)yttrium(III), yttrium(III) butoxide, tris(cyclopentadienyl)yttrium(III), and Y(thd) 3 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate), but are not limited thereto.

[0076] Exemplary erbium-containing precursors that can be used with ALD and CVD coating deposition techniques include tris-methylcyclopentadienyl erbium(III) (Er(MeCp) 3 ), erbium boranamide (Er(BA) 3 ), Er(TMHD) 3 , erbium(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionate), and tris(butylcyclopentadienyl)erbium(III), but are not limited thereto.

[0077] Exemplary aluminum-containing precursors that can be used with ALD and CVD coating deposition techniques include diethylaluminum ethoxide, tris(ethylmethylamide)aluminum, aluminum sec-butoxide, aluminum tribromide, aluminum trichloride, triethylaluminum, triisobutylaluminum, trimethylaluminum, and tris(diethylamide)aluminum, but are not limited thereto.

[0078] Exemplary zirconium-containing precursors that can be used with ALD and CVD coating deposition techniques include zirconium(IV) bromide, zirconium(IV) chloride, T-butoxyzirconium(IV), tetrakis(diethylamide)zirconium(IV), tetrakis(dimethylamide)zirconium(IV), tetrakis(ethylmethylamide)zirconium(IV), but are not limited thereto.

[0079] Exemplary oxygen-containing reactants and their equivalents that can be used with the various coating deposition techniques identified herein include, but are not limited to, ozone, water vapor, oxygen, oxygen radicals.

[0080] FIG. 11 shows a method 300 for forming a plasma-resistant protective coating including a rare earth oxide layer and a metal oxide barrier layer on an article. The article is, for example, a processing chamber component according to various embodiments. Using method 300, any article including an article having an aspect ratio from about 3:1 to about 300:1 (e.g., aspect ratios such as 20:1, 50:1, 100:1, 150:1, etc.) can be coated. This method may optionally be initiated by selecting the compositions of the rare earth oxide layer and the metal oxide barrier layer of the plasma-resistant protective coating and selecting the thicknesses of each of these layers. The composition of the rare earth oxide layer and the composition of the metal oxide barrier layer can be selected from any of the materials discussed above. The thicknesses selected for the rare earth oxide layer and the metal oxide barrier layer and the ratio of the two can also be selected from any of the thicknesses and ratios discussed above. The selection of the composition, the selection of the thickness, and the forming method can be performed by persons of the same organization or by persons of multiple organizations.

[0081] In block 310, the article is placed into an ALD or CVD deposition chamber. In block 320, the method includes depositing a plasma-resistant protective coating on the surface of the article using ALD or CVD. In one embodiment, in block 325, ALD or CVD is performed to deposit or co-deposit (in the case of a multi-element layer) a rare earth oxide layer. In one embodiment, the rare earth oxide layer includes yttrium oxide and may have a cubic crystal phase. In one embodiment, in block 330, ALD or CVD is performed to deposit or co-deposit (in the case of a multi-element layer) a metal oxide barrier layer. The metal oxide barrier layer may have an atomic crystal phase different from the cubic crystal phase of the crystalline rare earth oxide layer. The metal oxide barrier layer may be amorphous.

[0082] ALD and CVD are very conformal processes as implemented in various embodiments, and the surface roughness of the plasma-resistant protective coating may match the surface roughness of the underlying surface of the article being coated. The plasma-resistant protective coating may have a total thickness of from about 500 nm to about 10 μm, or from about 500 nm to about 5 μm in some embodiments. In other embodiments, the plasma-resistant protective coating may have a thickness of from about 500 nm to about 1 μm. The plasma-resistant protective coating may have a porosity of about 0% in some embodiments, or may be pore-free in some embodiments, and the variation in thickness across various portions of the coating may be about ±5% or less, ±10% or less, or ±20% or less.

[0083] In block 335, a decision may be made whether to add a further layer to the plasma-resistant protective coating (e.g., if attempting to form a multi-layer stack). If a further layer is added, the method returns to block 320 and a further rare earth oxide layer and metal oxide blocking layer may be formed by ALD or CVD. Otherwise, the plasma-resistant protective coating is fully formed and the method may reach completion.

[0084] Depending on the composition of the rare earth oxide layer, in block 325, a rare earth oxide of a target thickness may be deposited by one or more cycles of ALD or CVD. The target thickness of the rare earth oxide layer may range from 500 angstroms to about 5000 angstroms. In some embodiments, the rare earth oxide layer may be a multi-element rare earth oxide layer. The multi-element rare earth oxide layer may be deposited by sequential ALD deposition or sequential CVD deposition, or by co-deposition by simultaneously injecting a plurality of precursors together into the deposition chamber. Various ALD techniques are described in more detail with respect to FIGS. 1A - 1C, and it is understood that similar mechanisms may be utilized in CVD processing.

[0085] Similarly, depending on the composition of the metal oxide blocking layer, in block 330, a metal oxide blocking layer of a target thickness can be deposited by one or more cycles of ALD or CVD. The target thickness of the metal oxide blocking layer can range from about 1 angstrom to about 500 angstroms. In some embodiments, the metal oxide blocking layer can be a multi-element metal oxide blocking layer. The multi-element metal oxide blocking layer can be deposited by sequential ALD deposition or sequential CVD deposition, or by co-deposition by simultaneously injecting a plurality of precursors together into the deposition chamber. Various ALD techniques are described in more detail with respect to FIGS. 1A-1C, and it is understood that similar mechanisms can also be utilized in CVD processes.

[0086] The resistance of the coating material to plasma is measured by the "etch rate" (ER), whose unit is micron per hour (μm / hr), and the measurement period is the entire period during which the coated component is in operation and exposed to plasma. The processing time before measurement may vary. For example, the measurement may be performed before processing, after 50 processing hours, after 150 processing hours, after 200 processing hours, etc. As a result of variations in the composition of the plasma-resistant protective coating grown or deposited on the showerhead or other processing chamber components, a plurality of different plasma resistance or erosion rate values may occur. Furthermore, when a plasma-resistant protective coating having a single composition is exposed to various plasmas, a plurality of different plasma resistance or erosion rate values may occur. For example, the plasma-resistant material may have a first plasma resistance or erosion rate associated with a first type of plasma and a second plasma resistance or erosion rate associated with a second type of plasma. In embodiments, 200W of NF 3 After exposure to direct capacitively coupled plasma at 450 °C for 2 hours, no detectable erosion occurred.

[0087] The following examples are provided to assist in understanding the embodiments described herein and should not be construed as specifically limiting the embodiments described and claimed herein. Such variations, including all equivalent substitutions now known or later developed within the knowledge of those skilled in the art, and changes or minor modifications in the experimental design, should be considered to be within the scope of the embodiments incorporated herein. These examples can be achieved by performing the method 300 described above.

[0088] Example 1 - Al6061 Substrate and Al 2 O 3 A discontinuous ZrO 2 Blocking layer on the buffer layer to form a Y 2 O 3 Plasma-resistant protective coating. Figure 5A shows an Al 2 O 3 Plasma-resistant protective coating deposited on the buffer layer 520A on the aluminum substrate 510A of Al6061. A rare earth oxide layer 530A of crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. The deposition of the crystalline yttrium oxide layer was performed by injecting a yttrium-containing precursor into the deposition chamber containing the article, adsorbing the yttrium-containing precursor on the surface of the article, and forming a first half-reaction. Thereafter, an oxygen-containing reactant was injected into the deposition chamber to form a second half-reaction. This deposition cycle could be repeatedly executed until the target thickness was obtained.

[0089] Subsequently, a blocking layer 540A of a polycrystalline zirconium oxide layer was deposited on the single-phase crystalline yttrium oxide layer using atomic layer deposition. The deposition of the polycrystalline zirconium oxide layer was performed by injecting a metal-containing precursor (e.g., a zirconium-containing precursor) into the deposition chamber containing the article, adsorbing the metal-containing precursor (e.g., a zirconium-containing precursor) on the surface of the article, and forming a first half-reaction. Thereafter, an oxygen-containing reactant was injected into the deposition chamber to form a second half-reaction. This deposition cycle could be repeatedly executed until the target thickness was obtained.

[0090] These depositions were repeated for several cycles to form a stack of layers in which single-phase crystalline yttrium oxide layers (530A, 550A, 570A, 590A) and polycrystalline zirconium oxide layers (540A, 560A, 580A) overlapped alternately.

[0091] The first layer 530A in the plasma-resistant protective coating was a single-phase crystalline yttrium oxide layer. The crystalline yttrium oxide layer had a cubic phase of about 95 - 100 wt% corresponding to Powder Diffraction File (PDF) No. 04 - 005 - 4378. The single-phase crystalline yttrium oxide layer showed an X-ray diffraction (XRD) curve as shown in Fig. 6A.

[0092] The intermittent zirconium oxide layer in the plasma-resistant protective coating was polycrystalline with a tetragonal phase (also called tazheranite) of about 65.1 ± 5 wt% and a monoclinic phase (also called baddeleyite) of about 34.9 ± 5 wt%. The tetragonal phase of zirconia corresponded to PDF No. 01 - 070 - 8758. The monoclinic phase of zirconia corresponded to PDF No. 01 - 070 - 8739. The polycrystalline zirconium oxide layer showed an XRD curve as shown in Fig. 6B.

[0093] The thickness of each rare earth oxide layer (i.e., the crystalline yttrium oxide layer) was from about 240 nm to about 260 nm, and the thickness of the barrier layer (i.e., the polycrystalline zirconium oxide layer) was from about 0.5 nm to about 1.5 nm.

[0094] The zirconium oxide blocking layer within the plasma-resistant protective coating was characterized, among other things, using transmission electron microscopy and energy-dispersive spectroscopy (TEM / EDS) line scans. For analysis by TEM / EDS, a blocking layer of polycrystalline zirconium oxide was deposited to a sufficient thickness to be able to generate the atomic distribution of various atoms within the layer. The line scan is shown in FIG. 6C. The concentrations of oxygen 605, zirconium 625, and aluminum 632 are shown. The composition shown between 20 nm and 60 nm in the line scan corresponds to the composition of the polycrystalline zirconium oxide blocking layer. FIG. 6C shows that the polycrystalline zirconium oxide blocking layer contains approximately 25 atomic % zirconium and approximately 75 atomic % oxygen.

[0095] FIG. 6D shows a high-angle annular dark field (HAADF) scanning transmission electron microscope (STEM) image of the polycrystalline zirconium oxide blocking layer. This blocking layer is the one analyzed by TEM / EDS in FIG. 6C. Region 610 shows Al6061, region 620 shows the alumina buffer layer, and region 630 shows an exemplary polycrystalline zirconium oxide blocking layer. This blocking layer is the one analyzed by TEM / EDS in FIG. 6C. FIG. 6D also shows that the polycrystalline zirconium oxide layer deposited by ALD conformally and uniformly covers the Al6061 and the alumina buffer layer from low porosity to non-porous.

[0096] Example 2 - An Al6061 substrate and Al 2 O 3 A discontinuous Y x Zr y O z Blocking layer having Y 2 O 3 A plasma-resistant protective coating is formed. FIG. 5B shows Al 2 O 3Shows a plasma-resistant protective coating deposited on the buffer layer 520B. A rare earth oxide layer 530B of crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. Subsequently, a blocking layer 540B of crystalline zirconium-yttrium oxide (e.g., a solid solution of Y 2 O 3 -ZrO 2 ) was deposited on the crystalline yttrium oxide layer using atomic layer deposition. The crystalline yttrium oxide layer and the crystalline zirconium-yttrium oxide layer could be deposited in the same manner as the method described in Example 1.

[0097] The blocking layer 540B was deposited by sequential atomic layer deposition. Specifically, one cycle of zirconium oxide was deposited by atomic layer deposition, and then one cycle of yttrium oxide was deposited by atomic layer deposition. These two cycles (one cycle of ZrO 2 and one cycle of Y 2 O 3 ) are collectively referred to as a supercycle. The blocking layer 540B was completely grown in 4 supercycles.

[0098] The deposition of the single-phase crystalline yttrium oxide layer and the single-phase crystalline zirconium-yttrium oxide blocking layer was repeated for several cycles to form a stack of layers in which the crystalline yttrium oxide layers (530B, 550B, 570B, 590B) and the crystalline zirconium-yttrium oxide layers (540B, 560B, 580B) overlapped alternately.

[0099] The first layer 530B in the plasma-resistant protective coating was a single-phase crystalline yttrium oxide layer. The single-phase crystalline yttrium oxide layer had a cubic phase of about 95 - 100 wt% corresponding to Powder Diffraction File (PDF) No. 04-005-4378. The single-phase crystalline yttrium oxide layer showed an X-ray diffraction (XRD) curve as shown in FIG. 6A.

[0100] The intermittent zirconium-yttrium oxide layer within the plasma-resistant protective coating was single-phase crystalline with a tetragonal phase of approximately 95 to 100 wt%. The tetragonal phase of zirconium-yttrium oxide corresponded to PDF number 01-082-1243. The crystalline zirconium-yttrium oxide layer exhibited an XRD curve as shown in FIG. 7A. The XRD curve shown in FIG. 7A and the corresponding PDF number correlate with the chemical formula of Zr 0.86 Y 0.14 O 1.93 .

[0101] The thickness of each rare earth oxide layer (i.e., the crystalline yttrium oxide layer) was from about 240 nm to about 260 nm, and the thickness of the barrier layer (i.e., the crystalline zirconium-yttrium oxide layer) was from about 0.5 nm to about 1.5 nm, or about 0.8 nm.

[0102] The zirconium-yttrium oxide barrier layer within the plasma-resistant protective coating was characterized using, among other things, transmission electron microscopy and energy-dispersive spectroscopy (TEM / EDS) line scans. For analysis by TEM / EDS, the barrier layer of crystalline zirconium-yttrium oxide was deposited to a sufficient thickness to generate the atomic distribution of various atoms within the layer. The line scan is shown in FIG. 7B. The concentrations of oxygen 705, yttrium 712, zirconium 725, aluminum 732, and iridium 745 are shown. The composition shown between 40 nm and 90 nm in the line scan corresponds to the composition of the crystalline zirconium-yttrium oxide barrier layer. FIG. 7B shows that the crystalline zirconium-yttrium oxide barrier layer contains approximately 10 to 15 atomic% yttrium, approximately 20 to 25 atomic% zirconium, and approximately 60 to 65 atomic% oxygen.

[0103] Figure 7C shows a high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) image of a crystalline zirconium - yttrium oxide blocking layer. This blocking layer was analyzed by TEM / EDS in Figure 7B. Region 710 shows Al6061, region 720 shows the alumina buffer layer, and region 730 shows an exemplary polycrystalline zirconium oxide blocking layer. This blocking layer was analyzed by TEM / EDS in Figure 7B. Figure 7C also shows that the crystalline zirconium - yttrium oxide layer deposited by ALD conformally and uniformly covers the Al6061 and the alumina buffer layer with low porosity to non - porosity.

[0104] Figures 7D and 7E show transmission electron microscope (TEM) images of the crystalline zirconium - yttrium oxide layer, further demonstrating that the coating obtained by atomic layer deposition is conformal, uniform, and pore - free.

[0105] Example 3 - Al6061 substrate and Al 2 O 3 A discontinuous Y x Zr y O z Blocking layer is provided on the 2 O 3 A plasma - resistant protective coating is formed. Figure 5C shows a plasma - resistant protective coating deposited on an aluminum substrate 510C of Al6061 and on an Al 2 O 3 Buffer layer 520C. A rare - earth oxide layer 530C of single - phase crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. Subsequently, a blocking layer 540C of a mixed polycrystalline yttrium - zirconium oxide (e.g., Y 2 O 3 -ZrO 2 Solid solution) and a yttrium oxide layer was deposited on the single - phase crystalline yttrium oxide layer using atomic layer deposition. The single - phase crystalline yttrium oxide layer and the polycrystalline yttrium - zirconium oxide blocking layer could be deposited in a manner similar to the method described in Example 1.

[0106] The barrier layer 540C was deposited by sequential atomic layer deposition. Specifically, one cycle of zirconium oxide was deposited by atomic layer deposition, and then two cycles of yttrium oxide were deposited by atomic layer deposition. These three cycles (one cycle of ZrO 2 and two cycles of Y 2 O 3 ) are collectively referred to as a supercycle in this embodiment. The barrier layer 540C was completely grown in four supercycles.

[0107] The deposition of a single-crystalline yttrium oxide layer and a polycrystalline mixture of a yttrium-zirconium oxide and yttrium oxide barrier layer was repeated for several cycles to form a stack of layers in which single-crystalline yttrium oxide layers (530C, 550C, 570C, 590C) and polycrystalline yttrium-zirconium oxide and yttrium (540C, 560C, 580C) overlapped alternately.

[0108] The first layer 530C in the plasma-resistant protective coating was a single-crystalline yttrium oxide layer. The single-crystalline yttrium oxide layer had a cubic phase of about 95 - 100 wt% corresponding to Powder Diffraction File (PDF) No. 04-005-4378. The single-crystalline yttrium oxide layer showed an X-ray diffraction (XRD) curve as shown in FIG. 6A.

[0109] The intermittent mixture of yttrium-zirconium oxide and yttrium oxide layers in the plasma-resistant protective coating was polycrystalline with a cubic phase of about 64 - 74 wt% or about 69.4 wt% (corresponding to PDF No. 01-080-4014) and a cubic yttrium oxide phase of about 25 - 35 wt% or about 30.6 wt% (corresponding to PDF No. 01-084-3893). The polycrystalline barrier layer showed an XRD curve as shown in FIG. 8A. The XRD curve shown in FIG. 8A and the corresponding PDF number are for a chemical formula of about 69.4 ± 5 wt% of Zr 0.4 Y 0.6 O 1.7 and a chemical formula of about 30.6 ± 5 wt% of Y2 O 3 correlates with the chemical formula of. The phases of yttrium zirconium oxide and yttrium oxide are cubic, and the phase of the yttrium rare earth oxide layer is also cubic, but the lattice structures are different in various cubic phases. Therefore, as long as the lattice structures of the two crystal phases change, the barrier layer can have the same phase as the rare earth oxide layer.

[0110] The thickness of each rare earth oxide layer (i.e., the crystalline yttrium oxide layer) is from about 240 nm to about 260 nm, and the thickness of the barrier layer (i.e., the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide layers) is from about 0.5 nm to about 1.5 nm, or about 1.2 nm.

[0111] The barrier layer in the plasma-resistant protective coating was characterized, among other things, using transmission electron microscopy and energy-dispersive spectroscopy (TEM / EDS) line scans. For the analysis by TEM / EDS, a barrier layer of a polycrystalline mixture of yttrium zirconium oxide and yttrium oxide was deposited to a sufficient thickness to generate the atomic distribution of various atoms within the layer. The line scan is shown in FIG. 8B. The concentrations of oxygen 805, yttrium 812, zirconium 825, aluminum 832, and iridium 845 are shown. The composition shown between 30 nm and 480 nm in the line scan corresponds to the composition of the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide barrier layer. FIG. 8B shows that the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide barrier layer contains about 15 - 25 atomic % of yttrium, about 5 - 10 atomic % of zirconium, and about 65 - 75 atomic % of oxygen.

[0112] FIG. 8C shows a high angle annular dark field (HAADF) scanning transmission electron microscope (STEM) image of the multiphase crystalline mixture of yttrium-zirconium oxide and yttrium oxide barrier layers that were analyzed by TEM / EDS in FIG. 8B. Region 815 shows Al6061, and region 835 shows the exemplary multiphase crystalline mixture of yttrium-zirconium oxide and yttrium oxide barrier layers that were analyzed by TEM / EDS in FIG. 8B. FIG. 8C also shows that the multiphase crystalline mixture of yttrium-zirconium oxide and yttrium oxide layers deposited by ALD conformally and uniformly covers the Al6061 and alumina buffer layers with low to no porosity.

[0113] Figure 8D shows a transmission electron microscope (TEM) image of the multiphase crystalline mixture of yttrium zirconium oxide and yttrium oxide barrier layers, further demonstrating that the coating obtained by atomic layer deposition is conformal, uniform, and pore-free.

[0114] Example 4 - Al6061 substrate and Al 2 O 3 Intermittent Y on the buffer layer x Zr y O z Y with blocking layer 2 O 3 Forms a plasma-resistant protective coating. FIG. 9A shows Al deposited on an aluminum substrate 910 of Al6061. 2 O 3 9 shows a plasma resistant protective coating deposited on a buffer layer 920. A rare earth oxide layer 930 of single phase crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. A barrier layer 940 of a mixed multiphase crystalline yttrium-zirconium oxide and yttrium oxide layer was then deposited on the single phase crystalline yttrium oxide layer using atomic layer deposition. The single phase crystalline yttrium oxide layer and the multiphase crystalline yttrium-zirconium oxide barrier layer may be deposited in a manner similar to that described in Example 1.

[0115] The barrier layer 940 was deposited by sequential atomic layer deposition. Specifically, one cycle of zirconium oxide was deposited by atomic layer deposition, and then three cycles of yttrium oxide were deposited by atomic layer deposition. These four cycles (one cycle of ZrO 2 and three cycles of Y 2 O 3 ) are collectively referred to as a supercycle in this embodiment. The barrier layer 940 was completely grown in four supercycles.

[0116] The deposition of a single-crystalline yttrium oxide layer and a polycrystalline mixture of a barrier layer of yttrium zirconium oxide and yttrium oxide was repeated for several cycles to form a stack of layers in which the single-crystalline yttrium oxide layers (930, 950, 970, 990) and the polycrystalline mixtures of layers of yttrium zirconium oxide and yttrium oxide (940, 960, 980) overlapped alternately.

[0117] The first layer 930 in the plasma-resistant protective coating was a single-crystalline yttrium oxide layer. The single-crystalline yttrium oxide layer had a cubic phase of about 95 - 100 wt% corresponding to Powder Diffraction File (PDF) No. 04 - 005 - 4378. The single-crystalline yttrium oxide layer showed an X-ray diffraction (XRD) curve as shown in FIG. 6A.

[0118] The intermittent mixture of the yttrium zirconium oxide and yttrium oxide layers in the plasma-resistant protective coating was polycrystalline with a cubic phase of about 25 - 35 wt% or about 30.8 wt% (corresponding to PDF No. 01 - 080 - 4014) and a cubic yttrium oxide phase of about 64 - 74 wt% or about 69.2 wt% (corresponding to PDF No. 01 - 084 - 3893). The polycrystalline barrier layer showed an XRD curve as shown in FIG. 8A. The XRD curve shown in FIG. 8A and the corresponding PDF numbers are for about 30.8 ± 5 wt% of Zr 0.4 Y 0.6 O 1.7(That is, x is 0.6, y is 0.4, and z is 1.7) and about 69.2 ± 5 wt% of Y 2 O 3 correlates with the chemical formula. The phases of yttrium zirconium oxide and yttrium oxide are cubic, and the phase of the yttrium rare earth oxide layer is also cubic, but the lattice structures of the various cubic phases are different. Therefore, as long as the lattice structures of the two crystal phases are different, the barrier layer can have the same phase as the rare earth oxide layer.

[0119] Chemical formula Y x Zr y O z The x, y, and z of the chemical formula Y x Zr y O z are specified in this example and the previous example, but their values should not be construed as being limited, and the atomic ratio of yttrium to zirconium can range from 0 (when no yttrium is present) to 9. However, this is limited to the case where the resulting crystal phase is different from the crystal phase of the rare earth oxide layer.

[0120] The thickness of each rare earth oxide layer (i.e., the crystalline yttrium oxide layer) is from about 240 nm to about 260 nm, and the thickness of the barrier layer (i.e., the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide layers) is from about 0.5 nm to about 2.0 nm, or about 1.6 nm.

[0121] The barrier layer within the plasma-resistant protective coating was characterized, among other things, using transmission electron microscopy and energy-dispersive spectroscopy (TEM / EDS) line scans. For analysis by TEM / EDS, a barrier layer of a polycrystalline mixture of yttrium zirconium oxide and yttrium oxide was deposited to a sufficient thickness to generate atomic distributions of various atoms within the layer. The line scan is shown in FIG. 9B. The concentrations of oxygen 905, yttrium 912, zirconium 925, aluminum 932, and iridium 945 are shown. The composition shown between 40 nm and 85 nm in the line scan corresponds to the composition of the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide barrier layer. FIG. 9B shows that the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide barrier layer contains about 3-7 atomic % zirconium, about 15-25 atomic % zirconium, and about 65-75 atomic % oxygen.

[0122] FIG. 9C shows a high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) image of a polycrystalline mixture of a yttrium zirconium oxide and yttrium oxide barrier layer. This barrier layer was analyzed by TEM / EDS of FIG. 9B. Region 915 shows Al6061, and region 935 shows an exemplary polycrystalline mixture of a yttrium zirconium oxide and yttrium oxide barrier layer. This barrier layer was analyzed by TEM / EDS of FIG. 9B. FIG. 9C also shows that the polycrystalline mixture of the yttrium zirconium oxide and yttrium oxide layer deposited by ALD conformally and uniformly covers the Al6061 and alumina buffer layer from low porosity to non-porous.

[0123] FIG. 9D shows a transmission electron microscope (TEM) image of a polycrystalline mixture of a yttrium zirconium oxide and yttrium oxide barrier layer, further demonstrating that the coating obtained by atomic layer deposition is conformal, uniform, and pore-free.

[0124] Example 5 - Al6061 Substrate and Al2 O 3 Y having an intermittent gadolinium oxide blocking layer on the buffer layer 2 O 3 to form a plasma-resistant protective coating. FIG. 10 shows Al deposited on an aluminum substrate 1010 of Al6061 2 O 3 a plasma-resistant protective coating deposited on the buffer layer 1020. A rare earth oxide layer 1030 of single-crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. Subsequently, a blocking layer 1040 of gadolinium oxide was deposited on the single-crystalline yttrium oxide layer using atomic layer deposition.

[0125] The deposition of the single-crystalline yttrium oxide layer and the single-phase / multiphase crystalline gadolinium oxide blocking layer was repeated for several cycles to form a stack of layers in which the crystalline yttrium oxide layers (1030, 1050, 1070, 1090) and the crystalline gadolinium oxide layers (1040, 1060, 1080) overlap alternately.

[0126] Similar to the crystalline gadolinium oxide blocking layer, other amorphous or crystalline rare earth oxide blocking layers can be deposited between the yttrium oxide layers. When the blocking layer is crystalline, the atomic crystal phase of the blocking layer should be different from the atomic crystal phase of yttrium oxide or at least have a different lattice structure. If the crystal phases are different or the lattice structures are different, the blocking layer can suppress the growth of yttrium oxide grains from growing abnormally large uncontrollably.

[0127] Exemplary and non-limiting crystal phases related to various rare earth oxides are shown in FIG. 3. (For example, La 2 O 3 , Pr 2 O 3 , Nd 2 O 3 , Sm 2 O 3 , Eu 2 O 3 , Gd 2 O 3 , Tb 2 O3 , Dy 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , ZrO 2 and combinations thereof). In FIG. 3, the y-axis represents temperature and the x-axis represents rare earth oxides, and it is possible to identify in which crystalline single-phase or multi-phase a particular rare earth oxide exists when placed under the influence of a particular temperature. For example, at a particular ALD temperature, La 2 O 3 , Pr 2 O 3 , Nd 2 O 3 may have a hexagonal atomic phase, Sm 2 O 3 may have a hexagonal phase and / or a monoclinic phase, Eu 2 O 3 , Gd 2 O 3 , Tb 2 O 3 may exist in a monoclinic phase, Dy 2 O 3 may exist in a monoclinic phase and / or a cubic phase, Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 may exist in a cubic phase. In some embodiments, the crystalline metal oxide layer may include cubic phase YAG. As shown, region A includes a rare earth oxide type A structure, which is a hexagonal crystal structure. Region B includes a rare earth oxide type B structure, which is a monoclinic crystal structure. Region C includes a rare earth oxide type C structure, which is a cubic crystal structure. Region H includes a rare earth type H structure, which is a hexagonal crystal structure. Region X includes a rare earth oxide type X structure, which is a cubic crystal structure. As shown, Er 2 O 3It has a cubic structure.

[0128] Example 6 - Al6061 substrate and Al 2 O 3 Intermittent Y on the buffer layer x Zr y O z Y having a blocking layer 2 O 3 Form a plasma-resistant protective coating. Figure 12 shows an Al deposited on an aluminum substrate 1210 of Al6061 2 O 3 It shows a plasma-resistant protective coating deposited on the buffer layer 1220. A rare earth oxide layer 1230 of single-crystalline yttrium oxide was deposited on the aluminum oxide buffer layer using atomic layer deposition. Subsequently, a blocking layer 1240 of yttrium zirconium oxide was deposited on the single-crystalline yttrium oxide layer using atomic layer deposition. The single-crystalline yttrium oxide layer and the yttrium zirconium oxide blocking layer could be deposited in the same manner as the method described in Example 1.

[0129] The blocking layer 1240 was deposited by sequential atomic layer deposition. Specifically, 3 cycles of zirconium oxide were deposited by atomic layer deposition, and then 1 cycle of yttrium oxide was deposited by atomic layer deposition. These 4 cycles (3 cycles of ZrO2 and 1 cycle of Y 2 O 3 ) are collectively referred to as a supercycle in this example. The blocking layer 1240 was completely grown in 4 supercycles.

[0130] The deposition of the single-crystalline yttrium oxide layer and the yttrium zirconium oxide blocking layer was repeated for several cycles to form a stack of layers in which the single-crystalline yttrium oxide layers (1230, 1250, 1270, 1290) and the yttrium zirconium oxides (1240, 1260, 1280) overlap alternately.

[0131] The first layer 1230 within the plasma-resistant protective coating was a single-phase crystalline yttrium oxide layer. The single-phase crystalline yttrium oxide layer had a cubic phase of about 95 to 100 wt% corresponding to Powder Diffraction File (PDF) No. 04-005-4378. The single-phase crystalline yttrium oxide layer showed an X-ray diffraction (XRD) curve as shown in FIG. 6A.

[0132] The thickness of each rare earth oxide layer (i.e., the crystalline yttrium oxide layer) was from about 240 nm to about 260 nm, and the thickness of the barrier layer was from about 0.5 nm to about 2.0 nm, or about 1.6 nm.

[0133] The barrier layer within the plasma-resistant protective coating was characterized using, among other things, top-down scanning electron microscope (SEM) images, TEM images, and TEM / EDS line scans.

[0134] Top-down SEM images are shown in FIGS. 13A and 13B. FIG. 13A shows a top-down SEM image of a 1-μm yttria coating deposited by ALD without a barrier layer. As shown in FIG. 13A, large grown grains 1305 protrude from the surface coating. Region 1308 indicates a cutting position for TEM (e.g., a focused ion beam (FIB) cutting position). FIG. 13B shows a top-down SEM image of a 1-μm yttria coating with a barrier layer according to this example. As shown in FIG. 13B, there are no large grown grains protruding from the surface coating. Region 1310 indicates a cutting position for TEM (e.g., a focused ion beam (FIB) cutting position).

[0135] Cross-sectional TEM images are shown in FIGS. 14A and 14B. FIG. 14A shows a cross-sectional TEM image of a 1 μm yttria coating deposited by ALD without a blocking layer. FIG. 14A shows the TEM of a sample taken from cut position 1308. As shown in FIG. 14A, large grown grains 1405 protrude from the surface of the coating. FIG. 14B shows a cross-sectional TEM image of a 1 μm yttria coating with a blocking layer according to this example. FIG. 14B shows the TEM of a sample taken from cut position 1310. As shown in FIG. 14B, there are no grains that have grown large and protrude from the surface coating.

[0136] TEM / EDS line scans are shown in FIGS. 15A and 15B. The line scan is shown in FIG. 15A. The TEM / EDS line scan shows an Al substrate 1502 covered by a coating 1504, and the coating 1504 is covered by a FIB cap layer 1506. This composition showed three zirconium peaks between about 250 - 350 nm, about 500 - 600 nm, and about 750 - 850 nm (i.e., at the position of the blocking layer).

[0137] FIG. 15B shows a TEM image in which three blocking layers 1505, 1510, 1515 (each shown as a zirconium peak) identified by the line scan appear, and further demonstrates that the coating obtained by atomic layer deposition is conformal, uniform, and pore-free.

[0138] All blocking layers discussed and exemplified herein only suppress the uncontrolled grain growth of grains within the crystalline rare earth oxide layer. The blocking layer does not affect the crystal phase of the rare earth oxide layer.

[0139] The XRD data shown herein was obtained by grazing incidence XRD (GIXRD) with a PANalytical X’Pert Pro MRD 6-axis diffractometer equipped with a copper X-ray tube and parallel beam optics.

[0140] The TEM samples were prepared using in-situ focused ion beam (FIB) lift-out technique with a FEI Helios 650 Dual Beam FIB / SEM. Before machining, the samples were covered with sputtered iridium (Ir), protective carbon ink, and e-Pt / I-Pt. The thickness of the TEM lamella was approximately 100 nm.

[0141] The TEM samples were imaged in bright field (BF) TEM mode and high resolution (HR) TEM mode by operating a FEI Tecnai TF-20 FEG / TEM at 200 kV.

[0142] Z-contrast STEM is a form of Rutherford scattering where electrons are scattered at very large angles and collected with a special detector. The scattering is proportional to Z 2 and the resulting image can be directly interpreted as a qualitative chemical map. The contrast of the image is due to differences in average atomic weight, with larger atomic weights appearing brighter than smaller average atomic weights. Usually, these images have little diffraction contrast. These images are sometimes called high angle annular dark field images (HAADF). Z-contrast can display atomic columns in the highest resolution images.

[0143] The foregoing description has set forth numerous specific details, such as examples of specific systems, components, methods, etc., to provide a thorough understanding of some embodiments of the present invention. However, it will be apparent to those skilled in the art that at least some embodiments of the present invention may be practiced without these specific and detailed descriptions. In other instances, well-known components or methods have not been described in detail or are presented in a simple block diagram format to avoid unnecessarily obscuring the present invention. Accordingly, the specific and detailed descriptions are merely illustrative. Specific embodiments may differ from these illustrative descriptions, but are still considered to be within the scope of the present invention.

[0144] Throughout this specification, references to "an embodiment" or "one embodiment" mean that the particular configuration, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, appearances of the phrases "in an embodiment" or "in one embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Further, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or".

[0145] References throughout this specification to numerical ranges should not be construed as limiting, but rather should be understood to encompass the outer limits of the range as well as each number and / or narrower range enumerated within the recited numerical range.

[0146] The operations of the methods described herein are presented and described in a particular order, but the order of each method operation may be changed so that a particular operation is performed in a reverse order or so that an operation is performed at least partially in parallel with another operation. In another embodiment, the instructions or sub-operations of different operations may be performed intermittently and / or alternately.

[0147] It should be understood that the above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of ordinary skill in the art upon reading and understanding the above description. Accordingly, the scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

[Claim 1] 1. An article comprising a plasma-resistant protective coating on a surface thereof, the plasma-resistant protective coating comprising: A stack of alternating layers of crystalline rare earth oxide layers and crystalline or amorphous metal oxide layers, a first layer of the stack of alternating layers being a crystalline rare earth oxide layer; the crystalline rare earth oxide layer has a thickness of about 500 to 5000 angstroms; When the metal oxide layer is crystalline, the metal oxide layer has an atomic crystal phase that is different from the phase of the crystalline rare earth oxide layer; the metal oxide layer has a thickness of about 1 to 500 angstroms; An article comprising a stack in which a crystalline or amorphous metal oxide layer inhibits grain growth of a crystalline rare earth oxide layer.

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