Corrosion-resistant metal oxide coating deposited by atomic layer deposition.
A composite metal oxide coating using atomic layer deposition addresses the challenges of coating high aspect ratio features and plasma erosion by forming a homogeneous mixture of rare-earth metals, enhancing plasma resistance and stability in semiconductor processing.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2019-07-17
- Publication Date
- 2026-04-16
AI Technical Summary
Existing plasma-resistant coatings for semiconductor processing chambers fail to effectively coat high aspect ratio features and are prone to erosion and mechanical separation in harsh plasma environments, leading to particle contamination and wafer processing drift.
A composite metal oxide coating is formed using atomic layer deposition, comprising a homogeneous mixture of rare-earth metals and other metals like zirconium, hafnium, aluminum, and tantalum, which is co-deposited to provide enhanced plasma resistance and uniform coverage.
The coating significantly reduces erosion and mechanical separation, ensuring stable plasma processing by eliminating voids and phase separation, thereby improving particle performance and processing stability.
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Abstract
Description
[Technical Field]
[0001] Embodiments of this disclosure relate to corrosion-resistant metal oxide coatings, coated articles, and methods for forming such coatings using atomic layer deposition. Background
[0002] In the semiconductor industry, devices are fabricated through numerous manufacturing processes that produce increasingly smaller structures. Some manufacturing processes, such as plasma etching and plasma cleaning, involve exposing a substrate to a high-speed plasma stream to etch or clean it. Plasma can be highly corrosive and can corrode the processing chamber and other surfaces and components exposed to it. This corrosion can generate particles, which often contaminate the substrate during processing and contribute to device defects. Bromine-containing plasmas, which can contain bromine ions and radicals, are particularly harsh, and particle generation can occur from the interaction between the plasma and the material within the processing chamber. Plasma can also cause wafer processing drift due to changes in the surface chemistry of components induced by radical recombination.
[0003] As device shapes become smaller, susceptibility to defects increases, and the requirements for particulate contaminants (i.e., on-wafer performance) become more stringent. To minimize particulate contamination caused by plasma etching and / or plasma cleaning processes, plasma-resistant chamber materials have been developed. Examples of such plasma-resistant materials include ceramics made of Al2O3, AlN, SiC, Y2O3, quartz, and ZrO2. Different ceramics have different material properties (plasma resistance, stiffness, flexural strength, thermal shock resistance, etc.). Different ceramics also have different material costs. Therefore, there are ceramics with excellent plasma resistance, low-cost ceramics, and even ceramics with excellent flexural strength and / or thermal shock resistance.
[0004] Plasma spray coatings formed from Al2O3, AlN, SiC, Y2O3, quartz, and ZrO2 can reduce particle generation from chamber components, but these types of plasma spray coatings cannot penetrate and coat high aspect ratio features, such as the holes in a showerhead. While some deposition techniques can coat high aspect ratio features, the resulting coatings may erode and form particles in certain plasma environments, such as bromine-containing plasmas, or suffer from mechanical separation of material layers due to insufficient interdiffusion within the coating. Summary
[0005] The articles described by the embodiments specified herein comprise a body and a rare-earth metal-containing oxide coating on the surface of the body, wherein the rare-earth metal-containing oxide coating comprises about 1 mol% to about 40 mol% of a first metal and about 1 mol% to about 40 mol% of a second metal, the first metal and the second metal being independently selected from the group consisting of rare-earth metals, zirconium, hafnium, aluminum and tantalum, the first metal being distinct from the second metal, and the rare-earth metal-containing oxide coating comprising a homogeneous mixture of the first metal and the second metal.
[0006] Furthermore, embodiments of this specification include a method that includes a step of co-depositing a rare earth metal-containing oxide coating on the surface of an article using atomic layer deposition, wherein the step of co-depositing the rare earth metal-containing oxide coating includes a step of contacting the surface with a first precursor during a first period to form a partial metal adsorption layer containing a first metal (M1), the first precursor being selected from the group consisting of a rare earth metal-containing precursor, a zirconium-containing precursor, a hafnium-containing precursor, an aluminum-containing precursor, and a tantalum-containing precursor, and a step of contacting the partial metal adsorption layer with a second precursor different from the first precursor during a second period to form a partial metal adsorption layer containing a first metal (M1) and a second metal (M2 The present invention describes a method comprising the steps of: forming a co-adsorption layer containing a first metal, a second precursor selected from the group consisting of rare earth metal-containing precursors, zirconium-containing precursors, hafnium-containing precursors, aluminum-containing precursors, and tantalum-containing precursors, and the first metal being different from the second metal; and contacting the co-adsorption layer with a reactant to form a rare earth metal-containing oxide coating, wherein the rare earth metal-containing oxide coating contains about 1 mol% to about 40 mol% of the first metal and about 1 mol% to about 40 mol% of the second metal, and the rare earth metal-containing oxide coating contains a homogeneous mixture of the first metal and the second metal.
[0007] Furthermore, embodiments of this specification include a method comprising the step of co-depositing a rare earth metal-containing oxide coating on the surface of an article using atomic layer deposition, wherein the step of co-depositing the rare earth metal-containing oxide coating comprises the step of performing at least one co-injection cycle, the co-injection cycle comprising the step of contacting the surface with a mixture of a first precursor and a second precursor during a first period to form a co-adsorbed layer, wherein the first precursor and the second precursor each independently consist of a group of rare earth metal-containing precursors, zirconium-containing precursors, hafnium-containing precursors, aluminum-containing precursors and tantalum-containing precursors. A method is described comprising the steps of: a step selected from; and a step of contacting a co-adsorption layer with an oxygen-containing reactant to form a rare earth metal-containing oxide coating, wherein the rare earth metal-containing oxide coating comprises about 1 mol% to about 40 mol% of a first metal and about 1 mol% to about 40 mol% of a second metal, the first metal and the second metal being independently selected from the group consisting of rare earth metals, zirconium, hafnium, aluminum and tantalum, and the first metal being different from the second metal, and the rare earth metal-containing oxide coating comprising a homogeneous mixture of the rare earth metal and the additional metal.
[0008] Furthermore, this specification describes a method for depositing a rare earth metal-containing oxide coating on the surface of an article using atomic layer deposition, wherein the step of depositing the rare earth metal-containing oxide coating includes the steps of: contacting the surface with a first precursor during a first period to form a first metal adsorption layer; contacting the first metal adsorption layer with a reactant to form a first metal layer; contacting the first metal layer with a second precursor during a second period to form a second metal adsorption layer; contacting the second metal adsorption layer with a reactant to form a second metal layer; and forming a rare earth metal-containing oxide coating from the first and second metal layers, wherein the rare earth metal-containing oxide coating comprises about 1 mol% to about 40 mol% of a first metal and about 1 mol% to about 40 mol% of a second metal, and the first and second metals are independently selected from the group consisting of rare earth metals, hafnium, and tantalum, and the first metal is different from the second metal. [Brief explanation of the drawing]
[0009] The drawings in this disclosure are shown as examples, not as limitations, and similar reference numerals indicate similar elements. It should be noted that different references to “one” or “one” embodiment in this disclosure do not necessarily refer to the same embodiment, and such references mean at least one. [Figure 1] A cross-sectional view of the processing chamber is shown. [Figure 2A] This specification shows one embodiment of co-deposition treatment using the atomic layer deposition technique described herein. [Figure 2B] Another embodiment of co-deposition processing using the atomic layer deposition technique described herein is shown. [Figure 2C] Another embodiment of co-deposition processing using the atomic layer deposition technique described herein is shown. [Figure 2D] Another embodiment of co-deposition processing using the atomic layer deposition technique described herein is shown. [Figure 3A] This figure shows a method for forming a rare earth metal-containing oxide coating using the atomic layer deposition method described herein. [Figure 3B] This figure shows a method for forming a rare earth metal-containing oxide coating using the atomic layer deposition method described herein. [Figure 3C] This figure shows a method for forming a rare earth metal-containing oxide coating using the atomic layer deposition method described herein. [Figure 3D] This figure shows a method for forming a rare earth metal-containing oxide coating using the atomic layer deposition method described herein. [Figure 4A] These are transmission electron microscope images of sequentially deposited yttrium aluminum oxide coatings before exposure to plasma. [Figure 4B] This is a transmission electron microscope image of a yttrium aluminum oxide coating sequentially deposited on a substrate, after exposure to nitrogen trifluoride plasma. [Figure 4C]These are transmission electron microscope images of sequentially deposited yttrium zirconium oxide coatings after exposure to nitrogen trifluoride plasma. [Figure 5A] This is a transmission electron microscope image of a yttrium zirconium oxide coating co-deposited on a substrate. [Figure 5B] This is the EDS chart of the TEM / EDS line scan of the co-deposited coating in Figure 5A after exposure to nitrogen trifluoride plasma. [Figure 5C] Figure 5A shows a TEM image of the co-deposited coating obtained by a TEM / EDS line scan. [Figure 6A] This is a TEM image of a pure yttrium oxide coating after exposure to a fluorine-containing plasma. [Figure 6B] This is a TEM image of a co-deposited yttrium zirconium oxide coating after exposure to a fluorine-containing plasma. [Figure 7A] This is an EDS chart of a TEM / EDS line scan of a co-deposited coating. [Figure 7B] Figure 6A shows a TEM image of the co-deposited coating obtained by a TEM / EDS line scan. [Figure 8A] This is an EDS chart of a TEM / EDS line scan of a sequential deposition coating. [Figure 8B] Figure 8A shows a TEM image of a sequential deposition coating obtained by TEM / EDS line scan. Detailed explanation
[0010] The embodiments described herein relate to composite metal-containing oxide coatings that include a mixture of multiple metals. The embodiments also relate to coated articles and methods of forming such composite metal-containing oxide coatings using atomic layer deposition. The composite metal-containing oxide coating may include a first metal (M1) and a second metal (M2). Here, the first metal and the second metal are independently selected from rare earth metals, zirconium, tantalum, hafnium, and aluminum, and the first metal is different from the second metal. In certain embodiments, the rare earth metal-containing oxide coating may include three or more metals (e.g., M1, M2, M3, M4, etc.), and each metal is independently selected from rare earth metals (RE), zirconium, tantalum, hafnium, and aluminum. For example, the rare earth metal-containing oxide coating may be M1 x M2 y O z (e.g., Y x Zr y O z 、Y x Er y O z 、Y x Ta y O z etc.), M1 w M2 x M3 y O z (e.g., Y w Er x Zr y O z 、Y w Z rx Hf y O z etc.), M1 v M2 w M3 x M4 y O z (e.g., Y v Er w Z rx Hf y O z), and / or more complex composite metal oxide coatings having more mixed metals may also be present. As will be discussed in more detail below, multiple different metals (e.g., a first metal, a second metal, etc.) may be co-deposited onto an article using off-line techniques such as atomic layer deposition (ALD). Alternatively, multiple different metal oxides may be sequentially deposited and then interdiffused to form a composite metal oxide coating. The coating is resistant to the chemical properties of plasmas used in semiconductor processing, such as bromine-containing plasmas having bromine ions and bromine radicals.
[0011] According to embodiments described herein, the coating comprises multiple metals (e.g., RE) co-deposited on a single adsorption layer. w M y O z , Y x Zr y O z or RE w Y x Zr y O z ) may be formed from tantalum and at least one additional metal. In some embodiments, at least one metal is a rare earth metal. The at least one rare earth metal may be selected from yttrium, erbium, lanthanum, lutetium, scandium, gadolinium, samarium, or dysprosium. In certain embodiments, the coating may be formed from tantalum and at least one additional metal. The at least one additional metal may be selected in some embodiments from rare earth metals (RE), zirconium (Zr), aluminum (Al), hafnium (Hf), silicon (Si), and hafnium (Hf). According to various embodiments, the composite metal-containing oxide coating may contain about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol%, or about 10 mol% to about 25 mol%, or about 15 mol% to about 20 mol%, of a first metal (e.g., rare earth metals, tantalum, etc.), and about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol%, or about 10 mol% to about 20 mol%, of a second metal (e.g., rare earth metals, tantalum, aluminum, hafnium, silicon, etc.).
[0012] In certain embodiments, the coating comprises at least one rare earth metal (e.g., as a first metal) and at least one additional (e.g., a second) metal (e.g., RE) co-deposited on a single adsorption layer. w M y O z , Y x Zr y O z or RE w Y x Zr y O z ) may be formed from the following. The at least one rare earth metal may be selected from yttrium, erbium, lanthanum, lutetium, scandium, gadolinium, samarium, or dysprosium. Alternatively, the coating may be formed from tantalum and at least one additional metal. In some embodiments, the at least one additional metal may be selected from rare earth metals (RE), zirconium (Zr), aluminum (Al), hafnium (Hf), and silicon (Si). According to some embodiments, the rare earth metal-containing oxide coating may contain at least one rare earth metal in about 5 mol% to about 30 mol%, or about 10 mol% to about 25 mol%, or about 15 mol% to about 20 mol%, and at least one additional metal in about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol%, or about 10 mol% to about 20 mol%.
[0013] The coating provides resistance to erosion by plasmas (e.g., bromine-containing plasmas) used in semiconductor processing and chamber cleaning. Therefore, the coating provides good particle performance and processing stability during such processing and cleaning. In this specification, the terms “erosion-resistant coating” or “plasma-resistant coating” refer to coatings that have particularly low erosion rates when exposed to certain plasmas, chemicals, and radicals (e.g., fluorine-based plasmas, chemicals, and / or radicals; bromine-based plasmas, chemicals, and / or radicals; chlorine-based plasmas, chemicals, and / or radicals, etc.). The co-deposition methods described in the embodiments eliminate mechanical separation resulting from the sequential deposition of various metal oxides in separate layers, achieving a much more uniform coating on the angstrom scale and improving phase control (e.g., lack of interdiffusion, clearly leaving Y2O3 and ZrO2 phases within the coating). According to various embodiments, co-deposition results in a coating having a homogeneous mixture of metals, and without being bound by any particular theory, it is believed that voids are eliminated within the co-deposited coating, thereby preventing the diffusion of fluorine into the coating. For example, in coatings containing a mixture of Y2O3 and ZrO2 deposited by deposition techniques other than ALD, or deposited by ALD using sequential deposition techniques, one or more phase separations may occur at some locations. This may result in some voids in the Y2O3 phase, which may increase susceptibility to fluorination. In contrast, Y2O3 deposited using co-deposition and / or co-injection techniques x Zr y O z ALD deposition of (for example, a Y2O3-ZrO2 solid solution) can reduce or eliminate phase separation, resulting in a homogeneous mixture of Y and Zr. Co-deposition also offers the flexibility to adjust the ratio of deposited metals, for example, by adjusting the number and / or pulse duration, temperature, pressure, etc. This flexibility allows for the formation of coatings with specific molar ratios of two or more metals.
[0014] In some embodiments, the composite metal oxide coating has a two-metal composition (M1 × M2 y O z ), a three-metal composition (M1 w M2 x M3 y O z ), a four-metal composition (M1 v M2 w M3 x M4 y O z ), a five-metal composition (M1 u M2 v M3 w M4 x M5 y O z ), a six-metal composition (M1 t M2 u M3 v M4 w M5 x M6 y O z ), etc. In each composite metal oxide coating, the variables t, u, v, w, x, y, z may be positive integers or decimal values. Some exemplary values of t, u, v, w, x, y, z may be in the range of about 0.1 to about 10. In some embodiments, the composite metal oxide coating is a rare earth metal-containing oxide coating. In some embodiments, the rare earth metal-containing oxide coating is Y x Zr y O z , Er x Zr y O z , Y w Er x Zr y O z , Y w Er[[ID=z , Y x Hf y O z Er x Hf y O z , Y x Ta y O z Er x Ta y O z , Y w Er x Ta y O z , Y w Ta x Zr y O z , Y w Ta x Hf y O z Er w Ta x Zr y O z Er w Ta x Hf y O z and Y v Er w Ta x Hf y O z Selected from: In one embodiment, the rare earth metal-containing oxide coating may contain about 28.6 mol% yttrium, about 9.5 mol% zirconium, and about 61.9 mol% oxygen (corresponding to about 60 mol% Y2O3 and about 40 mol% ZrO2 in the case of the separated phase). In another embodiment, the rare earth metal-containing oxide coating may contain about 31.8 mol% yttrium, about 6.8 mol% zirconium, and about 61.36 mol% oxygen (corresponding to about 70 mol% Y2O3 and about 30 mol% ZrO2 in the case of the separated phase). In further embodiments, the rare earth metal-containing oxide coating may contain La w Y x Zr y O z Lu w Y x Zr y O z , Sc w Y x Zr yO z , Gd w Y x Zr y O z Sm w Y x Zr y O z DY w Y x Zr y O z La w Y x Zr y O z Lu w Y x Ta y O z , Sc w Y x Ta y O z , Gd w Y x Ta y O z Sm w Y x Ta y O z DY w Y x Ta y O z Er w Y x Hf y O z La w Y x Hf y O z Lu w Y x Hf y O z , Sc w Y x Hf y O z , Gd w Y x Hf y O z Sm w Y x Hf y O z DY w Y x Hf y O z It may include a composition selected from the following. In some embodiments, the coating is REw Z rx Al y O z For example, Y w Z rx Al y O z It may also contain other composite oxides.
[0015] Examples of yttrium-containing oxide compounds that can form plasma-resistant coatings include Y2O3, Y x Al y O z (For example, Y3 Al5O 12 ), Y x Zr y O z , Y x Hf y O z , Y a Z rx Al y O z , Y a Z rx Hf y O z , Y a Hf x Al y O z , Y v Zr w Hf x Al y O z or Y x Er y O z It may also contain yttrium. The yttrium content in the coating may range from about 0.1 mol% to nearly 100 mol%. In the case of yttrium-containing oxides, the yttrium content may range from about 0.1 mol% to nearly 100 mol%, and the oxygen content may range from about 0.1 mol% to nearly 100 mol%.
[0016] Examples of erbium-containing oxide compounds that can form plasma-resistant coatings include Er2O3, Er x Al y O z (For example, Er3Al5O 12 ), Er x Zry O z Er x Hf y O z Er a Z rx Al y O z Er a Z rx Hf y O z Er a Hf x Al y O z , Y x Er y O z and Er a Y x Zr y O z (For example, single-phase solid solutions of Y2O3, ZrO2, and Er2O3) may be included. The erbium content in the plasma-resistant coating may range from about 0.1 mol% to nearly 100 mol%. In the case of erbium-containing oxides, the erbium content may range from about 0.1 mol% to nearly 100 mol%, and the oxygen content may range from about 0.1 mol% to nearly 100 mol%.
[0017] Beneficially, Y2O3 and Er2O3 are miscible. A single-phase solid solution can be formed for any combination of Y2O3 and Er2O3. For example, a plasma-resistant coating that is a single-phase solid solution may be formed by co-depositing a mixture of Er2O3 slightly above 0 mol% and Y2O3 slightly below 100 mol%. Furthermore, a plasma-resistant coating that is a single-phase solid solution may be formed by combining a mixture of Er2O3 slightly above 0 mol% and Y2O3 slightly below 100 mol%. x Er y O zThe plasma-resistant coating may contain Y2O3 ranging from over 0 mol% to less than 100 mol% to Er2O3 ranging from over 0 mol% to less than 100 mol%. Some notable examples include 90-99 mol% Y2O3 and 1-10 mol% Er2O3, 80-89 mol% Y2O3 and 11-20 mol% Er2O3, 70-79 mol% Y2O3 and 21-30 mol% Er2O3, 60-69 mol% Y2O3 and 31-40 mol% Er2O3, 50-59 mol% Y2O3 and 41-50 mol% Er2O3. This includes O3, 40-49 mol% Y2O3 and 51-60 mol% Er2O3, 30-39 mol% Y2O3 and 61-70 mol% Er2O3, 20-29 mol% Y2O3 and 71-80 mol% Er2O3, 10-19 mol% Y2O3 and 81-90 mol% Er2O3, and 1-10 mol% Y2O3 and 90-99 mol% Er2O3. x Er y O z The single-phase solid solution may have a monoclinic cubic state at temperatures below approximately 2330°C.
[0018] Beneficial, ZrO2 can be combined with Y2O3 and Er2O3 to form a mixture of ZrO2, Y2O3 and Er2O3 (for example, Er a Y x Zr y O z A single-phase solid solution containing ) may be formed. a Er x Zr y O z The solid solution may have a cubic, hexagonal, tetragonal, and / or cubic fluorite structure. a Er x Zr y O zThe solid solution may contain more than 0 mol% to 60 mol% of ZrO2, more than 0 mol% to 99 mol% of Er2O3, and more than 0 mol% to 99 mol% of Y2O3. Some notable amounts of ZrO2 that may be used include 2 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 30 mol%, 50 mol%, and 60 mol%. Some notable amounts of Er2O3 and / or Y2O3 that may be used include 10 mol%, 20 mol%, 30 mol%, 40 mol%, 50 mol%, 60 mol%, 70 mol%, 80 mol%, and 90 mol%.
[0019] Y a Z rx Al y O z The plasma-resistant coating may contain more than 0 mol% to 60 mol% of ZrO2, more than 0 mol% to 99 mol% of Y2O3, and more than 0 mol% to 60 mol% of Al2O3. Some notable amounts of ZrO2 that may be used include 2 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 30 mol%, 50 mol%, and 60 mol%. Some notable amounts of Y2O3 that may be used include 10 mol%, 20 mol%, 30 mol%, 40 mol%, 50 mol%, 60 mol%, 70 mol%, 80 mol%, and 90 mol%. Some notable amounts of Al2O3 that may be used include 2 mol%, 5 mol%, 10 mol%, 20 mol%, 30 mol%, 40 mol%, 50 mol%, and 60 mol%. In one embodiment, Y a Z rx Al y O z The plasma-resistant coating contains 42 mol% Y2O3, 40 mol% ZrO2, and 18 mol% Y2O3 and has a lamellar structure. In another embodiment, Y a Z rx Al y O z The plasma-resistant coating contains 63 mol% Y2O3, 10 mol% ZrO2, and 27 mol% Er2O3, and has a lamellar structure.
[0020] In some embodiments, the rare earth metal-containing oxide coating comprises about 1 mol% to about 40 mol% or about 5 mol% to about 30 mol% of a primary metal (e.g., rare earth metals such as yttrium and erbium) and about 1 mol% to about 40 mol% or about 1 mol% to about 20 mol% of a secondary metal (e.g., rare earth metals, Zr, Hf, Ta, Al, Si). In further embodiments, the composite metal oxide coating comprises about 1 mol% to about 40 mol% or about 5 mol% to about 30 mol% of Ta and about 1 mol% to about 40 mol% or about 1 mol% to about 20 mol% of a secondary metal (e.g., RE, Zr, Hf, Al, Si). In various embodiments, the coating comprises about 5 mol% to about 30 mol% of yttrium and about 1 mol% to about 20 mol% of zirconium, hafnium, or tantalum, or about 10 mol% to about 25 mol% of yttrium and about 5 mol% to about 17 mol% of Zr, Hf, or Ta, or about 15 mol% to about 21.5 mol% of yttrium and about 10 mol% to about 14.5 mol% of Zr, Hf, Al, Ta, or Si. In some embodiments, the composite metal oxide coating comprises about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol%, of yttrium, and about 1 mol% to about 40 mol%, or about 1 mol% to about 20 mol%, of zirconium, hafnium, or tantalum, or about 10 mol% to about 25 mol%, of yttrium, and about 5 mol% to about 17 mol%, of Zr, Hf, or Ta, or about 15 mol% to about 21.5 mol%, of yttrium, and about 10 mol% to about 14.5 mol%, of Zr, Hf, or Ta. In some embodiments, the coating comprises a mixture of Y and Er, where the combined mol% of Y and Er is about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol% (for example, it may contain 1 to 29 mol% of Y and 1 to 29 mol% of Er). The coating may further contain approximately 1 mol% to approximately 40 mol%, or approximately 1 mol% to approximately 20 mol%, of zirconium, hafnium, or tantalum.
[0021] In some embodiments, the thickness of the composite metal oxide coating or rare earth metal-containing oxide coating may be about 5 nm to about 10 μm, or about 5 nm to about 5 μm, or about 25 nm to about 5 μm, or about 50 nm to about 500 nm, or about 75 nm to about 200 nm. In some embodiments, the thickness of the composite metal oxide coating or rare earth metal-containing oxide coating may be about 50 nm, or about 75 nm, or about 100 nm, or about 125 nm, or about 150 nm. The composite metal oxide coating or rare earth metal-containing oxide coating may conformally cover one or more surfaces of the body of an article (including high aspect ratio features such as gas holes) with a substantially uniform thickness. In one embodiment, the composite metal oxide coating or rare earth metal-containing oxide coating conformally covers the substrate surface, and this surface is covered with a uniform thickness (including the covered surface features), where the thickness variation is less than approximately + / -20%, + / -10%, + / -5%, or smaller.
[0022] In further embodiments, the composite metal oxide coating or rare earth metal-containing oxide coating does not include separate layers containing oxides of the first metal and the second metal (or third, fourth, etc., metal). In particular, in certain embodiments, the composite metal oxide coating or rare earth metal-containing oxide coating does not have to be formed by a sequential atomic layer deposition cycle of multiple metals. Rather, in some embodiments, for example, the first and second metals may be co-deposited on the article or the body of the article. As a result, the rare earth metal-containing oxide coating can avoid mechanical separation between the layers containing the first metal and the layers containing the second metal. As a further result of the co-deposition process, the composite metal oxide coating or rare earth metal-containing oxide coating may contain a homogeneous mixture of the first metal (e.g., a rare earth metal) and the second metal without performing annealing. It also does not have to include a concentration gradient of the first or second metal resulting from incomplete interdiffusion of the materials within the coating.
[0023] In alternative embodiments, sequential atomic layer deposition (ALD) is performed. For sequential ALD, a first metal precursor may be adsorbed onto the surface, and an oxygen-based reactant may react with the adsorbed first metal (e.g., a rare earth metal, tantalum, etc.) to form a first metal oxide layer. Subsequently, a second metal precursor may be adsorbed onto the first metal oxide layer, and an oxygen-based reactant may react with the adsorbed second metal (e.g., zirconium, aluminum, hafnium, tantalum, silicon, etc.) to form a second metal oxide layer. Then, the metals from the first and second metal oxide layers may interdiffuse with each other. When a coating is deposited using a sequential deposition cycle of the first and second metals, annealing may be performed to influence interdiffusion between the layers. Such annealing can create a concentration gradient of the metal phase from the surface toward the substrate article (e.g., Y2O3 and ZrO2 to YZrO), and such a coating lacks homogeneity throughout. The co-deposition coating described herein forms a homogeneous mixture of the first and second metals. Generally, annealing to facilitate interdiffusion is not performed.
[0024] According to various embodiments, the composite metal oxide coating or rare earth metal-containing oxide coating may be formed from a multilayer stack having alternating material layers. In one embodiment, a buffer layer may be deposited on the surface of an article or the body of an article, and the composite metal oxide coating or rare earth metal-containing oxide coating may be deposited on the buffer layer. The buffer layer may include, but is not limited to, aluminum oxide (e.g., Al2O3), silicon oxide (e.g., SiO2), aluminum nitride, or a combination thereof. In other embodiments, a first metal (e.g., yttrium, erbium, tantalum, etc.) and a second metal (e.g., rare earth metal, zirconium, aluminum, hafnium, tantalum, etc.) may be co-deposited on (or on, if a buffer layer is used) an article using ALD to form a first co-deposited layer. For example, a second layer of material such as a metal oxide, a rare earth metal oxide, or a co-deposited rare earth metal zirconium oxide may be deposited or co-deposited on the first co-deposited layer. Each deposition or co-deposition cycle can be repeated a desired number of times to achieve the target composition and / or target thickness of the final multilayer coating.
[0025] The thickness of each layer in a multilayer composite metal oxide coating or rare earth metal-containing oxide coating may range from about 10 nm to about 1.5 μm. In some embodiments, the buffer layer (e.g., amorphous Al2O3) may have a thickness of about 1.0 μm, and the rare earth metal-containing oxide layer may have a thickness of about 50 nm. The ratio of the thickness of the composite metal oxide coating or rare earth metal-containing oxide layer to the thickness of the buffer layer may be 200:1 to 1:200, or about 100:1 to 1:100, or about 50:1 to about 1:50. The thickness ratio may be selected according to the specific chamber application.
[0026] The composite metal oxide coating or rare earth metal-containing oxide coating may be grown or co-deposited with a precursor using ALD. However, this precursor is a precursor for co-deposition of a first metal oxide layer containing tantalum and / or at least one rare earth metal (e.g., yttrium, erbium, etc.) and a second metal (e.g., RE, Zr, Ta, Hf, Al, Si). In one embodiment, the composite metal oxide coating or rare earth metal-containing oxide coating has a polycrystalline structure.
[0027] The buffer layer may contain amorphous aluminum oxide or a similar material. The buffer layer provides robust mechanical properties, increases dielectric strength, provides better adhesion of the composite metal oxide coating or rare earth metal-containing oxide coating to the constituent (e.g., formed from Al6061, Al6063, or ceramic), and can prevent cracking of the composite metal oxide coating or rare earth metal-containing oxide coating at the following temperatures: up to about 350°C, or up to about 300°C, or up to about 250°C, or up to about 200°C, or from about 200°C to about 350°C, or from about 250°C to about 300°C. Such metal articles have a coefficient of thermal expansion significantly larger than that of the composite metal oxide coating or rare earth metal-containing oxide coating. The harmful effects of the mismatch in coefficients of thermal expansion between the article and the composite metal oxide coating may be addressed by first providing the buffer layer 209. Since ALD is used for deposition, it can coat the inner surfaces of high aspect ratio features such as showerheads or gas supply holes in gas supply lines, thus protecting the entire component from exposure to corrosive environments. In some embodiments, the buffer layer may include a material having a coefficient of thermal expansion between the coefficient of thermal expansion of the article and the coefficient of thermal expansion of the composite metal-containing oxide coating. Furthermore, the buffer layer can act as a barrier preventing the migration of metallic contaminants (e.g., trace metals such as Mg and Cu) from the component or article into the composite metal oxide coating. Adding an amorphous Al2O3 layer as a buffer layer beneath the composite metal oxide coating may increase the overall thermal resistance of the composite metal oxide coating. This is due to the relief of high stresses concentrated in several areas of the composite metal oxide / Al6061 interface.
[0028] In various embodiments, the buffer layer may be Al2O3, such as amorphous Al2O3. Amorphous Al2O3 may have higher temperature performance than, for example, rare earth metal-containing oxides. Therefore, adding an amorphous Al2O3 layer as a buffer layer beneath the composite metal oxide coating may increase the overall thermal resistance of the composite metal oxide coating. This is due to the relaxation of high stresses concentrated in several areas of the composite metal oxide / Al6061 interface. Furthermore, Al2O3 has good adhesion to aluminum-based components because it shares the element (i.e., aluminum). Similarly, Al2O3 also has good adhesion to composite metal oxides because it shares the element (i.e., oxide). These improvements to the interface reduce interfacial defects that are prone to cracking. In addition, the amorphous Al2O3 layer can act as a barrier to prevent the migration of metal contaminants (e.g., trace metals such as Mg and Cu) from the components or articles into the rare earth metal-containing oxide layer.
[0029] This specification also describes articles having composite metal oxide coatings or rare earth metal-containing oxide coatings as described above. In various embodiments, the articles may be any type of component for use in a semiconductor processing chamber, examples of which include, but are not limited to, electrostatic chucks, gas supply plates, chamber walls, chamber liners, doors, rings, shower heads, nozzles, plasma generation units, high-frequency electrodes, electrode housings, diffusers, and gas lines. The articles may contain, but are not limited to, materials including aluminum (Al), silicon (Si), copper (Cu), and magnesium (Mg). In various embodiments, the articles may contain aluminum oxide (Al x O y ), silicon oxide (Si x O yThe material may contain, but is not limited to, ceramic materials including aluminum nitride (AlN) or silicon carbide (SiC) material. In some embodiments, the article or body of the article may be made of aluminum Al6061 or Al6063 material. In some embodiments, the surface roughness of the surface of the article or body of the article is about 120 μin to about 180 μin, or about 130 μin to about 170 μin, or about 140 μin to about 160 μin.
[0030] The composite metal oxide coatings are extremely dense, and their porosity can be approximately 0% (for example, in some embodiments, rare earth metal-containing oxide coatings may be porosity-free). The composite metal oxide coatings may be resistant to corrosion and erosion due to the chemical properties of plasma etching. These chemical properties include the chemical properties of CCl4 / CHF3 plasma etching, HCl3Si etching, and NF3 and bromine-containing etching. Furthermore, the composite metal oxide coatings described herein, having a buffer layer, may be resistant to cracking and delamination at temperatures up to approximately 350°C. For example, the rare earth metal-containing oxide coatings and chamber components having buffer layers described herein may be used in processes that include heating to a temperature of approximately 200°C. Even when the chamber components undergo thermal repetitions between room temperature and approximately 200°C, no cracking or delamination will occur in the rare earth metal-containing oxide coating.
[0031] In some embodiments, the article or body of the article includes at least one feature (e.g., a gas vent), the aspect ratio (L:D) of the feature's length to diameter is approximately 5:1 to approximately 300:1, or approximately 10:1 to approximately 200:1, or approximately 20:1 to approximately 100:1, or approximately 5:1 to approximately 50:1, or approximately 7:1 to approximately 25:1, or approximately 10:1 to approximately 20:1. A composite metal oxide coating or a rare earth metal-containing oxide coating may conformally cover the surface of the article body and the feature. In some embodiments, the article or body of the article includes features (e.g., channels), and the aspect ratio (D:W) of the depth to width of the features may be about 5:1 to about 300:1, or about 10:1 to about 200:1, or about 20:1 to about 100:1, or about 5:1 to about 50:1, or about 7:1 to about 25:1, or about 10:1 to about 20:1. A composite metal oxide coating or a rare earth metal-containing oxide coating may conformally cover the surface of the body of the article and the features.
[0032] In various embodiments, high aspect ratio features of articles (as described above) can be effectively coated with the composite metal oxide coatings or rare earth metal-containing oxide coatings described herein. The composite metal oxide coatings may have one phase, two phases, or three or more phases. The composite metal oxide coatings or rare earth metal-containing oxide coatings are conformal within the high aspect ratio features and can cover the features with a substantially uniform thickness, as described above. Figure 1 is a cross-sectional view of a semiconductor processing chamber 100 having one or more chamber components. These chamber components are coated with composite metal oxide coatings or rare earth metal-containing oxide coatings according to embodiments described herein. The substrate of at least some of the chamber components is Al (e.g., Al x O y , AlN, Al6061, or Al6063), Si (for example, Si x O yThe material may include one or more of the following: SiO2, or SiC, copper (Cu), magnesium (Mg), titanium (Ti), and stainless steel (SST). The processing chamber 100 may be used for processing that generates a corrosive plasma environment having a plasma processing state (e.g., bromine-containing plasma). For example, the processing chamber 100 may be a chamber for a plasma etcher or plasma etching reactor, a plasma cleaner, or a reactor for plasma CVD or ALD. Examples of chamber components that may include a composite metal oxide coating or a rare earth metal-containing oxide coating include chamber components having complex shapes and features having a high aspect ratio as described above. Some exemplary chamber components include a substrate support assembly, an electrostatic chuck, a ring (e.g., a process kit ring or a single ring), a chamber wall, a base, a gas distribution plate, a shower head, a gas line, a nozzle, a lid, a liner, a liner kit, a shield, a plasma screen, a flow balancer, a cooling base, a chamber viewport, and a chamber lid.
[0033] In one embodiment, the processing chamber 100 comprises a chamber body 102 surrounding an internal volume 106 and a shower head 130. The shower head 130 may comprise a shower head base and a shower head gas distribution plate. Alternatively, the shower head 130 may be replaced in some embodiments by a lid and nozzles, or in other embodiments by a plurality of fan-shaped shower head compartments and a plasma generation unit. The chamber body 102 may be manufactured from aluminum, stainless steel, or other suitable material. The chamber body 102 generally comprises side walls 108 and a bottom 110. An outer liner 116 may be positioned adjacent to the side walls 108 to protect the chamber body 102. The shower head 130 (or lid and / or nozzles), the side walls 108, and / or the bottom 110 may be coated with a rare earth metal-containing oxide coating.
[0034] An exhaust port 126 may be defined within the chamber body 102, and the internal volume 106 may be connected to a pump system 128. The pump system 128 may include one or more pumps and throttle valves, which may be used to evacuate the internal volume 106 of the processing chamber 100 and adjust the pressure.
[0035] The shower head 130 may be supported by the side wall 108 of the chamber body 102. The shower head 130 (or lid) may be open to allow access to the internal volume 106 of the processing chamber 100, and while closed, the processing chamber 100 can be sealed. A gas panel 158 may be connected to the processing chamber 100 to supply processing gas and / or cleaning gas to the internal volume 106 through the shower head 130 or the lid and nozzle. The shower head 130 may be used in a processing chamber used for dielectric etching (etching dielectric materials). The shower head 130 may comprise a gas distribution plate (GDP) having a plurality of gas supply holes 132 throughout. The shower head 130 may comprise a GDP bonded to an aluminum base or an anodized aluminum base. The GDP may be made from Si or SiC, or Y2O3, Al2O3, Y3Al5O 12 Ceramic materials such as (YAG) may also be used.
[0036] A lid may be used instead of a showerhead in the processing chamber used for conductive etching (etching conductive materials). The lid may have a central nozzle that fits into a central hole in the lid. The lid may be made of ceramics such as Al2O3, Y2O3, YAG, or a ceramic compound containing a solid solution of Y4Al2O9 and Y2O3-ZrO2. The nozzle may also be made of ceramics such as Y2O3, YAG, or a ceramic compound containing a solid solution of Y4Al2O9 and Y2O3-ZrO2.
[0037] Examples of process gases that can be used to process the substrate in the processing chamber 100 include halogen-containing gases (particularly C2F6, SF6, SiCl4, HBr, NF3, CF4, CHF3, CH2F3, F, NF3, Cl2, CCl4, BCl3, and SiF4), as well as gases such as O2 or N2O. Examples of carrier gases and purge gases include N2, He, Ar, and other gases that are inert to the process gas (e.g., non-reactive gases).
[0038] The substrate support assembly 148 is located under the showerhead 130 or lid within the internal volume 106 of the processing chamber 100. The substrate support assembly 148 includes a support 136 for holding the substrate 144 during processing. The support 136 is attached to the end of a shaft (not shown) which is connected to the chamber body 102 via a flange 164. The substrate support assembly 148 may include, for example, a heater, an electrostatic chuck, a susceptor, a vacuum chuck, or other substrate support assembly components.
[0039] Figure 2A shows one embodiment of co-deposition treatment 200 using ALD technology, in which a first metal-rich oxide coating is grown or deposited on an article. Figure 2B shows another embodiment of co-deposition treatment using ALD technology as described herein, in which a second metal-rich rare earth metal oxide coating is grown or deposited on an article. Figure 2C shows another embodiment of co-deposition treatment using ALD technology as described herein. Figure 2D shows another embodiment of co-deposition treatment using ALD technology as described herein, utilizing co-injection of rare earth metals and other metals.
[0040] In the ALD co-deposition process, both the adsorption of at least two precursors onto the surface and the reaction between the adsorbed precursors and the reactants may be referred to as "half-reactions." During the first half-reaction, the first precursor (or a mixture of precursors) may be rhythmically delivered to the surface of article 205 for a sufficient amount of time to partially (or completely) adsorb the precursor onto the surface. This adsorption is self-limiting because the precursor adsorbs onto numerous available sites on the surface, forming a partially adsorbed layer of the first metal on the surface. Sites already adsorbed with the first metal of the precursor become unavailable for further adsorption with subsequent precursors. Alternatively, some sites adsorbed with the first metal of the first precursor may be replaced with the second metal of the second precursor adsorbed on those sites. To complete the first half-reaction, the second precursor may be rhythmically delivered to the surface of article 205 for a sufficient amount of time to partially or completely adsorb the second metal of the second precursor onto available sites on the surface (or replace the first metal of the first precursor) to form a co-deposition adsorption layer on the surface.
[0041] The co-deposition cycle of the ALD process begins with a first precursor (i.e., chemical A, or a mixture of chemicals A and B) overflowing into the ALD chamber and being partially (or completely) adsorbed onto the surface of the article (including the surfaces of holes and features within the article). A second precursor (i.e., chemical B) may then be overflowed into the ALD chamber and adsorbed onto the remaining exposed surfaces of the article. The excess precursor may then be flushed out / purged from the ALD chamber (i.e., with an inert gas), followed by the introduction of a reactant (i.e., chemical R) into the ALD chamber, and then the reactant may be flushed out. Alternatively or additionally, the chamber may be purged during the first half-reaction between the deposition of the first precursor and the deposition of the second precursor. In the case of ALD, the final thickness of the material depends on the number of reaction cycles performed, as each reaction cycle grows a layer of a specific thickness, such as one atomic layer or a fraction of one atomic layer.
[0042] Aside from being a conformal process, ALD is also a uniform process, capable of forming very thin films, for example, with a thickness of approximately 3 nm or more. The same or nearly identical amount of material is deposited on all exposed surfaces of the article. Because ALD technology can deposit thin layers of material at relatively low temperatures (e.g., approximately 25°C to 350°C), it does not damage or deform any of the constituent materials. Additionally, ALD technology can also deposit layers of material within complex features of constituent materials (e.g., high aspect ratio features). Furthermore, ALD technology generally produces relatively thin (i.e., less than 1 μm) coatings that are pore-free (i.e., pinhole-free). This eliminates the possibility of crack formation during deposition.
[0043] A composite metal oxide coating or a rare earth metal-containing oxide coating is reacted with a first metal-containing precursor (e.g., a rare earth metal-containing precursor, a tantalum-containing precursor, etc.), a second metal-containing precursor, and an oxygen-containing reactant (e.g., oxygen gas (O2), water vapor (H2O), ozone (O3), oxygen radical (O3)). * The metal may be grown or deposited using ALD together with (or other oxygen-containing material). In some embodiments, the first metal-containing precursor may include yttrium, erbium, lanthanum, lutetium, scandium, gadolinium, samarium, dysprosium, or tantalum.
[0044] In various embodiments, the first metal-containing precursor and the second metal-containing precursor (in the case of a composite metal coating, the third metal-containing precursor and the fourth metal-containing precursor, etc.) are independently selected from yttrium-containing precursors. Examples of yttrium-containing precursors include tris(N,N-bis(trimethylsilyl)amide)yttrium(III), yttrium(III) butoxide, or yttrium cyclopentadienyl compounds (e.g., tris(cyclopentadienyl)yttrium (Cp3Y), tris(methylcyclopentadienyl)yttrium ((CpMe)3Y), tris(butylcyclopentadienyl)yttrium, tris(cyclopentadienyl)yttrium, or tris(ethylcyclopentadienyl)yttrium). Other yttrium-containing precursors that can be used include yttrium-containing amide compounds (e.g., tris(N,N-diisopropylformamidinate)yttrium, tris(2,2,6,6-tetramethylheptane-3,5-dionate)yttrium, or tris(bis(trimethylsilyl)amide)lanthanum), and yttrium-containing β-diketnate compounds. In some embodiments, the rare earth metal-containing oxide precursor may also contain erbium. Erbium-containing precursors include, but are not limited to, erbium-containing cyclopentadienyl compounds, erbium-containing amide compounds, and erbium-containing β-diketnate compounds. Examples of erbium-containing precursors for ALD include tris-methylcyclopentadienylerbium(III) (Er(MeCp)3), erbium boranamide (Er(BA)3), Er(TMHD)3, erbium(III) tris(2,2,6,6-tetramethyl-3,5-heptane dionate), and tris(butylcyclopentadienyl)erbium(III). Zirconium-containing precursors may include, but are not limited to, zirconium-containing cyclopentadienyl compounds, zirconium-containing amide compounds, and zirconium-containing β-diketnate compounds.Examples of zirconium-containing precursors for ALD include zirconium(IV) bromide, zirconium(IV) chloride, zirconium(IV) tert-butoxide, tetrakis(diethylamide)zirconium(IV), tetrakis(dimethylamide)zirconium(IV), tetrakis(ethylmethylamide)zirconium(IV), or zirconium cyclopentadienyl compounds. Examples of zirconium-containing precursors include tetrakis(dimethylamide)zirconium, tetrakis(diethylamide)zirconium, tetrakis(N,N'-dimethylformamidinate)zirconium, tetra(ethylmethylamide)hafnium, pentakis(dimethylamide)tantalum, and tris(2,2,6,6-tetramethylheptane-3,5-dioneate)erbium.
[0045] In some embodiments, the first metal-containing precursor and the second metal-containing precursor may be independently selected from cyclopentadienyl precursors, tris(methylcyclopentadienyl)yttrium ((CH3Cp)3Y), tris(butylcyclopentadienyl)yttrium, tris(cyclopentadienyl)yttrium, tris(ethylcyclopentadienyl)yttrium, amidinate precursors, tris(N,N'-diisopropylformamidinate)yttrium, tris(2,2,6,6-tetramethylheptane-3,5-dionate)yttrium, tris(bis(trimethylsilyl)amide)lanthanum, amide precursors, and β-diketnate precursors.
[0046] In some embodiments, a mixture of two precursors is introduced together (i.e., co-injected). Here, the mixture comprises a first proportion of a first metal-containing precursor and a second proportion of a second metal-containing precursor. For example, the precursor mixture may contain about 1 wt% to about 90 wt%, or about 5 wt% to about 80 wt%, or about 20 wt% to about 60 wt%, of the first metal-containing precursor and about 1 wt% to about 90 wt%, or about 5 wt% to about 80 wt%, or about 20 wt% to about 60 wt%, of the second metal-containing precursor. The mixture has a ratio of the first metal (e.g., yttrium, tantalum, etc.)-containing precursor to the second metal-containing precursor, and the ratio may be suitable for forming the target type of oxide material. The atomic ratio of the primary metal (e.g., yttrium, tantalum, etc.)-containing precursor to the secondary metal-containing precursor may be about 200:1 to about 1:200, or about 100:1 to about 1:100, or about 50:1 to about 1:50, or about 25:1 to about 1:25, or about 10:1 to about 1:10, or about 5:1 to about 1:5.
[0047] In one embodiment, a composite metal oxide coating or a rare earth metal-containing oxide coating is co-deposited onto the surface of an article using atomic layer deposition. The co-depositing step of the rare earth metal-containing oxide coating may include a step of contacting the surface with a first metal-containing precursor (e.g., a rare earth metal-containing precursor) during a first period to form a partially metal-adsorbed layer. The first metal-containing precursor may be one of a rare earth metal-containing precursor, a zirconium-containing precursor, a tantalum-containing precursor, a hafnium-containing precursor, an aluminum-containing precursor, or a silicon-containing precursor. Subsequently, the partially metal-adsorbed layer is contacted with a second metal-containing precursor different from the first metal-containing precursor during a second period to form a co-adsorbed layer containing the first and second metals. The second metal-containing precursor may be at least one of a rare earth metal-containing precursor, a zirconium-containing precursor, a hafnium-containing precursor, a tantalum-containing precursor, or an aluminum-containing precursor. After that, the co-adsorbed layer is contacted with an oxygen source reactant to form a rare earth metal-containing oxide coating. In certain embodiments, the coating may contain about 1 mol% to about 40 mol%, or about 5 mol% to about 30 mol%, of a rare earth metal or tantalum, and about 1 mol% to about 40 mol%, or about 1 mol% to about 20 mol%, of a secondary metal. Furthermore, the rare earth metal-containing oxide coating may contain a homogeneous mixture of the primary and secondary metals.
[0048] Referring to Figure 2A, a first metal (M1)-second metal (M2) co-deposition method 200 for depositing a rare earth metal-containing oxide coating on an article 205 is described. Article 205 may be introduced for a period of time into a first metal-containing precursor 210 (e.g., a rare earth metal-containing precursor) until the surface of article 205 is partially adsorbed with the first metal-containing precursor 210, forming a partially metal-adsorbed layer 215. Subsequently, article 205 may be introduced for a period of time into a second metal-containing precursor 220 until the remaining exposed surface of the article is adsorbed with the second metal-containing precursor 220, forming a co-adsorbed layer 225 containing both the first and second metals. The first metal-containing precursor exposed to an uncoated surface (i.e., having all available adsorption sites) can be adsorbed to the surface more efficiently than the second metal-containing precursor exposed to a partially adsorbed surface. Therefore, the co-adsorbed layer 225 is rich in the first metal. In other words, it may contain the first metal at a higher atomic concentration than the second metal. Next, article 205 is introduced into the reactant 230 for a period of time during which it reacts with the co-adsorption layer 225 to form the solid oxide layer of the rare earth metal-containing oxide coating 235 according to the embodiments described herein (e.g., Y x Zr y O z Alternatively, a Y2O3-ZrO2 solid solution may be grown. The precursor may be any of the above precursors. The co-deposition of the first and second metals with the introduction of reactants is called the M1-M2 co-deposition cycle. By repeating the M1-M2 co-deposition cycle m times, a coating of the desired thickness can finally be achieved.
[0049] Referring to Figure 2B, an M2-M1 co-deposition method 202 for depositing a rare-earth metal-containing oxide coating on article 205 is described. Article 205 may be introduced into a second metal-containing precursor 220 for a period of time until the surface of article 205 is partially adsorbed by the second metal-containing precursor 220, forming a partial metal adsorption layer 216. Subsequently, article 205 may be introduced into a first metal-containing precursor 210 for a period of time until the remaining exposed surface of the article is adsorbed by the first metal-containing precursor 220, forming a co-adsorption layer 226. The co-adsorption layer 226 may be rich in the second metal. Next, article 205 may be introduced into a first reactant 230 and reacted with the co-adsorption layer 225 to grow a solid layer (e.g., YZrO) of the rare-earth metal-containing oxide coating 236 according to the embodiments described herein. The precursor may be any of the above precursors. The co-deposition of a secondary metal and a primary metal, accompanied by the introduction of reactants, is called the M2-M1 co-deposition cycle. By repeating the M2-M1 co-deposition cycle n times, a coating of the desired thickness can eventually be achieved.
[0050] Each layer of the rare-earth metal-containing oxide coatings 235 and 236 may be uniform, continuous, and conformal. In some embodiments, the rare-earth metal-containing oxide coatings 235 and 236 may be porosity-free (e.g., zero porosity) or have near-zero porosity (e.g., 0% to 0.01%). In some embodiments, after one ALD deposition cycle, each layer of the rare-earth metal-containing oxide coatings 235 and 236 may have a thickness of less than one atomic layer to several atoms. Some organometallic precursor molecules are large. After reacting with reactants, the large organic ligands disappear, leaving behind much smaller metal atoms. In one complete ALD cycle (e.g., including the introduction of the precursor and the subsequent introduction of the reactants), the thickness may be less than one atomic layer. In co-deposition method 200, the co-deposition cycle may be repeated m times to reach the target thickness of coating 235. Similarly, in co-deposition method 202, the co-deposition cycle may be repeated n times to reach the target thickness of coating 236. m and n may be positive integer values.
[0051] The relative concentrations of the primary metal (e.g., rare earth metals, such as Ta) and the secondary metal may be controlled by the type of precursor used, the temperature of the ALD chamber during adsorption of the precursor onto the surface of the article, the time a particular precursor remains in the ALD chamber, and the partial pressure of the precursor. For example, using a tris(N,N-bis(trimethylsilyl)amide)yttrium(III) precursor may result in a lower atomic percentage of yttria than using a yttrium cyclopentadienyl precursor.
[0052] In some embodiments, three or more metal precursors are adsorbed onto the surface of article 205 in a single co-deposition cycle. For example, the co-deposition cycle may include the adsorption of a yttrium precursor onto the surface, followed by the adsorption of a zirconium precursor onto the surface, followed by the adsorption of a hafnium precursor onto the surface. With each subsequent precursor, a smaller amount of the associated metal may be adsorbed onto the surface. Thus, by selecting the order in which each precursor is adsorbed onto the surface to form a co-adsorption layer, a target ratio of two or more different metals can be achieved. Further exemplary co-deposition methods that can be performed include the M1-M2-M3 co-deposition method, in which a first metal (M1) is adsorbed onto the surface, followed by the adsorption of a second metal (M2), followed by the adsorption of a third metal (M3), followed by the introduction of an oxygen source reactant. Another exemplary co-deposition method that can be performed includes the M2-M1-M3 co-deposition method. In this co-deposition method, the second metal (M2) is adsorbed onto the surface, followed by the first metal (M1), followed by the third metal (M3), and then the oxygen-source reactant is introduced. Another exemplary co-deposition method that can be performed is the M3-M1-M2 co-deposition method. In this co-deposition method, the third metal (M3) is adsorbed onto the surface, followed by the first metal (M1), followed by the second metal (M2), and then the oxygen-source reactant is introduced. Another exemplary co-deposition method that can be performed is the M3-M2-M1 co-deposition method. In this co-deposition method, the third metal (M3) is adsorbed onto the surface, followed by the second metal (M2), followed by the first metal (M1), and then the oxygen-source reactant is introduced. More precursors may be adsorbed onto the surface to create more complex composite metal oxides. The more metals used, the greater the number of possible rearrangements.
[0053] Referring to Figure 2C, in some embodiments, a multilayer stack may be deposited on article 205 using a co-deposition ALD treatment 203. An optional buffer layer 209, as described above, may be deposited on article 205. In embodiments where the buffer layer 209 is alumina (Al2O3), in the first half-reaction, article 205 (e.g., Al6061 substrate) may be introduced into an aluminum-containing precursor (e.g., trimethylaluminum (TMA)) (not shown) for a period of time until all reaction sites on the surface are used up. The remaining aluminum-containing precursor may be flushed out of the reaction chamber, and then a reactant (not shown) of H2O or another oxygen source may be injected into the reactor to initiate the second half-reaction. After the Al-containing adsorbed layer produced by the first half-reaction reacts with H2O molecules, the Al2O3 buffer layer 209 may be formed.
[0054] The buffer layer 209 may be uniform, continuous, and conformal. In some embodiments, the buffer layer 209 may be porosity-free (e.g., zero porosity) or have near-zero porosity (e.g., 0% to 0.01%). Multiple complete ALD deposition cycles may be performed to deposit a buffer layer 209 having a target thickness. Each complete cycle (e.g., including the introduction and removal of an aluminum-containing precursor, the introduction of an H2O reactant, and another removal) further increases the thickness by a fraction of an atom to several atoms. In some embodiments, the thickness of the buffer layer 209 may be about 10 nm to about 1.5 μm, or about 10 nm to about 15 nm, or about 0.8 μm to about 1.2 μm.
[0055] Next, the M1-M2 co-deposition cycle described above with respect to Figure 2A, or the M2-M1 co-deposition cycle described above with respect to Figure 2B, may be performed on an article 205 having an optional buffer layer 209. The buffer layer 209, rather than the surface or body of the article, partially adsorbs the first metal-containing precursor 210 or the second metal-containing precursor 220, and attempts to form a partially adsorbed layer 215. After that, the precursors are flushed out of the ALD chamber using an inert gas (e.g., nitrogen), and then the M2-M1 co-deposition cycle described above with respect to Figure 2B, or the M1-M2 co-deposition cycle described above with respect to Figure 2A, may be performed on an article 205 having an optional buffer layer 209 and an M1-M2 coating layer 235.
[0056] The rare-earth metal-containing oxide layer resulting from the M1-M2 co-deposition cycle may contain a first proportion of the first metal and a second proportion of the second metal. The M2-M1 co-deposition cycle results in an additional layer containing a third proportion of the first metal and a fourth proportion of the second metal. In some embodiments, the third proportion may be lower than the first proportion and the fourth proportion may be higher than the third proportion. Thus, by using two co-deposition cycles, a multilayer coating having a buffer layer 209, an M1-M2 layer 235, and an M2-M1 layer 236 can be formed. Conventionally, either or both of the co-deposition cycles may be repeated m or n times, where m and n are integers greater than zero and represent the number of co-deposition cycles. In some embodiments, the ratio of m to n may be 1:50 to about 50:1, or about 1:25 to about 25:1, or about 1:10 to about 10:1, or about 1:2 to about 2:1, or 1:1. The coating can be fabricated by performing co-deposition cycles continuously and / or alternately. The alternating layers 235 and 236, as described with respect to Figure 2C, were formed in a 1:1 manner by the co-deposition cycle. Here, there is one layer of the M1-M2 coating layer for each of the M2-M1 coating layers. However, other patterns may exist in other embodiments. For example, two M1-M2 co-deposition cycles may be followed by one M2-M1 co-deposition cycle (2:1), and then this sequence may be repeated once more.
[0057] According to various embodiments, the M1-M2 codeposition cycle can be represented as m*(M1+M2+O), where m is an integer greater than zero and represents the number of M1-M2 codeposition cycles, M1 represents the amount (mol%) of deposited primary metal (e.g., rare earth metals such as yttrium and tantalum), M2 represents the amount (mol%) of deposited secondary metal, and O represents the amount (mol%) of deposited oxygen. The M2-M1 codeposition cycle can be represented as n*(M2+M1+O), where n is an integer greater than zero and represents the number of M2-M1 codeposition cycles, M2 represents the amount (mol%) of deposited secondary metal, M1 represents the amount (mol%) of deposited primary metal (e.g., rare earth metals such as yttrium and tantalum), and O represents the amount (mol%) of deposited oxygen.
[0058] As shown in Figure 2C, the target composition of the rare earth metal-containing coating can be achieved using the following formula. K*[m*(M1+M2+O)+n*(M2+M1+O)] Here, K is an integer greater than zero and represents the number of supercycles performed to achieve the target thickness. By adjusting K, m, and n, a coating of the desired composition (e.g., a desired ratio of the first metal to the second metal) can be achieved regardless of the chemical properties of the precursor.
[0059] Figure 2C shows co-deposition using two different metals. However, in further embodiments, co-deposition may be performed using three or more metals, as described above. When using three or more metals, there can be three or more possible co-deposition sequences. For example, in the case of co-deposition of three metals, the following co-deposition methods may be mixed to achieve a coating of the target composition: namely, M1+M2+M3+O, M1+M3+M2+O, M2+M1+M3+O, M2+M3+M1+O, M3+M1+M2+O, and M3+M2+M1+O. Therefore, the target composition may be achieved using the following formula. K*[a*(M1+M2+M3+O)+b*(M1+M3+M2+O)+c*(M2+M1+M3+O)+d*(M2+M3+M1+O)+e*(M3+M1+M2+O)+f*(M3+M2+M1+O)] Here, a, b, c, d, e, and f are non-negative integers. The number of moles of M1, M2, and M3 in each co-deposition method may be determined experimentally. Similarly, in the case of co-deposition of four metals, the following co-deposition methods may be mixed to achieve a coating of the target composition: namely, M1+M2+M3+M4+M2+O, M1+M4+M2+M3+O, M1+M3+M2+M4+O, M1+M4+M3+M2+O, M1+M2+M4+M3+O, M2+M1+M3+M4+O, M2+M4+M1+M3+O, M2+M4+M3+M4+O, M2+M4+M3+M1+O These are M3+M1+M2+M4+O, M3+M2+M4+M1+O, M3+M4+M1+M2+O, M3+M1+M4+M2+O, M3+M2+M1+M4+O, M3+M4+M2+M1+O, M4+M1+M2+M3+O, M4+M2+M3+M1+O, M4+M3+M1+M2+O, M4+M1+M3+M2+O, M4+M2+M1+M3+O, and M4+M3+M3+M1+O. Therefore, the target composition may be achieved using the following formula. K*[a*(M1+M2+M3+M4+O)+b*(M1+M3+M4+M2+O)+c*(M1+M4+M2+M3+O)+d*(M1+M3+M2+M4+O)+e*(M1+M4+M3+M2+O)+f*(M1+M2+M4+M3+ O)+g*(M2+M1+M3+M4+O)+h*(M2+M3+M4+M1+O)+i*(M2+M4+M1+M3+O)+j*(M2+M1+M4+M3+O)+k(M2+M3+M1+M4+O)+l*(M2+M4+M3+M1+O) +m*(M3+M1+M2+M4+O)+n*(M3+M2+M4+M1+O)+o*(M3+M4+M1+M2+O)+p*(M3+M1+M4+M2+O)+q*(M3+M2+M1+M4+O)+r*(M3+M4+M2+M1+O) +s*(M4+M1+M2+M3+O)+t*(M4+M2+M3+M1+O)+u*(M4+M3+M1+M2+O)+v*(M4+M1+M3+M2+O)+w*(M4+M2+M1+M3+O)+x*(M4+M3+M3+M1+O)] Here, a through x are non-negative integers.
[0060] The injection time ratio may be expressed as the ratio of the exposure time of the first metal (e.g., yttrium) precursor to the exposure time of the second metal precursor. It should be noted that the injection time and time ratio of the precursor material are controllable. On the other hand, adhesion to the surface of the precursor, the coefficient of adhesion, and chemical interactions may not be controllable. The pressure and temperature of the ALD chamber also affect the adsorption to the surface of the precursor. For example, since zirconium is slightly more reactive than yttrium, a coating obtained using a mixture of zirconium and yttrium may be zirconium-rich. Under equilibrium conditions in the chamber, the injection time can be adjusted to achieve the desired composition. At equilibrium, the composition is limited by the chemical reactivity of the precursor and the coefficient of adhesion of the material. In some embodiments, there is no purging between the introduction of the first metal-containing precursor and the second metal-containing precursor, as this may affect the adsorption of the material to the article.
[0061] In some embodiments, the ratio of the first number of M1-M2 co-deposition cycles to the second number of M1-M2 co-deposition cycles may be selected to obtain a first target mol% of the first metal and a second target mol% of the second metal as a result. Furthermore, multiple deposition supercycles may be performed, where each deposition supercycle includes the step of performing a first number of M1-M2 co-deposition cycles and the step of performing a second number of M2-M1 deposition cycles.
[0062] The ratio of the thickness of the first metal-containing oxide layer to the thickness of the buffer layer may be 200:1 to 1:200, or about 100:1 to 1:100, or about 50:1 to 1:50. Higher ratios of the rare-earth metal-containing oxide layer to the buffer layer (e.g., 200:1, 100:1, 50:1, 20:1, 10:1, 5:1, 2:1, etc.) may provide higher corrosion and erosion resistance. Conversely, lower ratios of the rare-earth metal-containing oxide layer to the buffer layer (e.g., 1:2, 1:5, 1:10, 1:20, 1:50, 1:100, 1:200) may provide higher heat resistance (e.g., improved resistance to cracking and / or delamination caused by thermal cycling). The thickness ratio may be selected according to the specific chamber application. In one embodiment, for a capacitively coupled plasma environment with a high sputtering rate, a 1 μm top layer may be deposited on a 50 nm buffer Al2O3 layer. For high-temperature chemical or radical environments without active ion bombardment, a 100 nm top layer with a 500 nm bottom layer may be optimal.
[0063] Referring to Figure 2D, article 205 may be inserted into the ALD chamber. In this embodiment, the co-deposition process includes the step of simultaneously co-injecting at least two precursors onto the surface of the article. Article 205 may be introduced into a mixture of precursors 210 and 220 for a period of time until the surface of the article or the body of the article is completely adsorbed with the mixture of precursors 210 and 220, forming a co-adsorption layer 227. A mixture of two precursors A and B (e.g., a yttrium-containing precursor and another rare-earth metal oxide precursor) is co-injected into the chamber in any number of ratios AxBy (e.g., A90+B10, A70+B30, A50+B50, A30+B70, A10+A90, etc.) and adsorbed onto the surface of the article. In these embodiments, x and y are expressed as atomic ratios (mol%) relative to Ax+By. For example, A90+B10 is 90 mol% A and 10 mol% B. In some embodiments, at least two precursors are used. In other embodiments, at least three precursors are used, and in further embodiments, at least four precursors are used. Subsequently, the article 205 having the co-adsorption layer 227 may be introduced into the reactant 230 and reacted with the co-adsorption layer 227 to grow a solid rare earth metal-containing oxide coating 235. As shown in the figure, the co-deposition by co-injection of the rare earth metal-containing coating 235 may be repeated m times to achieve a desired coating thickness, where m is an integer greater than 1.
[0064] ALD processing may be carried out at various temperatures depending on the type of processing. The optimal temperature range for a particular ALD processing is called the "ALD temperature window." Temperatures below the ALD temperature window may result in low growth rates and non-ALD type deposition. Temperatures above the ALD temperature window may result in reactions caused by the chemical vapor deposition (CVD) mechanism. The ALD temperature window may be in the range of about 100°C to about 650°C. In some embodiments, the ALD temperature window is about 20°C to about 200°C, or about 25°C to about 150°C, or about 100°C to about 120°C, or about 20°C to 125°C.
[0065] ALD processing enables conformal rare-earth metal oxide coatings with uniform thickness on articles and surfaces with complex geometric shapes, high aspect ratio holes (e.g., micropores), and three-dimensional structures. By providing sufficient exposure time for each precursor to the surface, the precursors can be dispersed and reacted completely across the entire surface (including all complex three-dimensional features). The exposure time used to obtain conformal ALD on high aspect ratio structures is proportional to the square of the aspect ratio and can be predicted using modeling techniques. Furthermore, ALD technology has advantages over other commonly used coating techniques because it allows for the synthesis of materials in specific compositions or formulations on demand, without the need for the long and difficult production of raw materials (such as powder materials and sintered targets).
[0066] Another usable ALD deposition technique involves the sequential deposition of multiple different metal oxide layers, followed by interdiffusion between the layers. This involves introducing a first precursor for the first metal, then introducing a first reactant to form the first metal oxide layer. Subsequently, a second metal-containing precursor for the second metal may be introduced, followed by the introduction of the first or second reactant to form the second metal oxide layer. In some embodiments, an annealing operation may then be performed.
[0067] In some embodiments, two or more of the above-described ALD deposition techniques may be combined to produce a homogeneous metal oxide coating. For example, co-deposition and co-injection may be combined, co-deposition and sequential deposition may be combined, and / or co-injection and sequential deposition may be combined. In one embodiment, a mixture of yttrium precursor and erbium precursor may be sprayed into the ALD chamber to adsorb yttrium and erbium onto the surface of the article. Subsequently, a mixture of zirconium precursor and hafnium precursor may be sprayed into the ALD chamber to further adsorb zirconium and hafnium onto the surface. Subsequently, an oxygen source reactant may be sprayed into the ALD chamber to adsorb Y v Er w Z rx Hf yO z A coating may be formed.
[0068] Figure 3A shows Method 300 for forming a rare earth metal-containing oxide coating by co-deposition ALD treatment. Method 300 may be used to coat any article described herein. Method 300 may optionally begin with the selection of a precursor for forming the coating. The selection of composition and the formation method may be carried out by the same organization or by multiple organizations.
[0069] Method 300 may optionally include a step in block 305 of cleaning the article with an acidic solution. In one embodiment, the article is immersed in a bath of the acidic solution. In various embodiments, the acidic solution may be a hydrofluoric acid (HF) solution, a hydrochloric acid (HCl) solution, a nitric acid (HNO3) solution, or a combination thereof. The acidic solution is capable of removing surface contaminants from the article and / or oxides from the surface of the article. The step of cleaning the article with an acidic solution may improve the quality of the coating deposited using ALD. In one embodiment, a quartz chamber component is cleaned using an acidic solution containing about 0.1 to 5.0 vol% HF. In one embodiment, an Al2O3 article is cleaned using an acidic solution containing about 0.1 to 20 vol% HCl. In one embodiment, an article made of aluminum and additional metal is cleaned using an acidic solution containing about 5 to 15 vol% HNO3.
[0070] In block 310, the article is loaded into the ALD deposition chamber. In block 325, method 300 optionally includes the step of depositing a buffer layer on the surface of the article or the body of the article using ALD. In block 320, ALD is performed to co-deposit a rare earth metal-containing oxide coating onto the article. At least one M1-M2 co-deposition cycle 330 is performed. The M1-M2 co-deposition cycle includes the step in block 335 of introducing a first metal-containing precursor into the ALD chamber containing the article (with or without the buffer layer). The first metal-containing precursor comes into contact with the surface of the article or the body of the article to form a partially metal-adsorbed layer. In block 340, a second metal-containing precursor is introduced into the ALD chamber containing the article having the partially metal-adsorbed layer. The second metal precursor comes into contact with the remaining exposed surfaces of the article or the body of the article to form the M1-M2 co-adsorbed layer. In block 345, the reactant is introduced into the ALD chamber and reacted with the M1-M2 co-adsorption layer to form a rare earth metal-containing oxide coating.
[0071] Figure 3B shows method 302 for forming a rare earth metal-containing oxide coating by co-deposition ALD treatment. Method 302 may be used to coat any article described herein. Method 302 may optionally begin with the selection of a precursor for forming the coating. The selection of composition and the formation method may be carried out by the same organization or by multiple organizations.
[0072] Method 302 may optionally include a step in block 305 of cleaning the article with an acidic solution. In block 310, the article is loaded into the ALD deposition chamber. In block 325, Method 302 optionally includes a step of depositing a buffer layer on the surface of the article or the body of the article using ALD. In block 321, ALD is performed to co-deposit a first metal-containing oxide coating onto the article. At least one M2-M1 co-deposition cycle 331 is performed. The M2-M1 co-deposition cycle includes a step in block 336 of introducing a second metal-containing precursor into the ALD chamber containing the article (with or without the buffer layer). The second metal-containing precursor comes into contact with the surface of the article or the body of the article to form a partially metal-adsorbed layer. In block 341, the first metal-containing precursor is introduced into the ALD chamber containing the article having the second metal-adsorbed layer. The first metal-containing precursor comes into contact with the article or the remaining exposed surface of the article's body to form an M2-M1 co-adsorption layer. In block 346, the reactant is introduced into the ALD chamber and reacts with the M2-M1 co-adsorption layer to form a rare earth metal-containing oxide coating.
[0073] Figure 3C shows a composite method 303 for forming a multilayer coating as described herein, which includes the step of performing at least one M1-M2 co-deposition cycle in block 330. Subsequently, the ALD chamber is purged with an inert gas in block 332. At least one M2-M1 co-deposition cycle is performed in block 350 to form a rare earth metal-containing oxide coating. As described above, the co-deposition cycle may be repeated any number of times and in any order to achieve a rare earth metal-containing coating of a desired composition. Although not shown, in some embodiments the deposited coating may be annealed. When the second metal is aluminum, annealing temperatures up to about 500°C may be used for coating.
[0074] Figure 3D shows Method 304 for co-depositing rare earth metal-containing oxide coatings according to embodiments described herein by co-injection. Method 304 may optionally include a step of cleaning the article with an acidic solution in block 305. In block 310, the article is loaded into an ALD deposition chamber. In block 325, Method 302 optionally includes a step of depositing a buffer layer on the surface of the article or the body of the article using ALD.
[0075] In block 322, ALD is performed to co-deposit a rare earth metal-containing oxide coating onto article 205 by co-injection. At least one co-deposition cycle 332 is performed. The co-deposition cycle includes the step of introducing a mixture of a first metal-containing precursor and a second metal-containing precursor into an ALD chamber containing the article (with or without a buffer layer) in block 355. The first and second metal-containing precursors may independently contain metals selected from rare earth metals, zirconium, aluminum, hafnium, and tantalum. The mixture of precursors comes into contact with the surface of the article or the body of the article to form a co-adsorbent layer. In block 360, reactants are introduced into the ALD chamber and reacted with the co-adsorbent layer to form a rare earth metal-containing oxide coating. The co-deposition cycle may be repeated as many times as necessary to achieve a coating of the desired thickness.
[0076] According to various embodiments, the method may include a step of co-depositing a rare earth metal-containing oxide coating on the surface of an article using atomic layer deposition. The step of co-depositing the rare earth metal-containing oxide coating may include a step of contacting the surface with a first metal-containing precursor or a second metal-containing precursor during a first period to form a partial metal adsorption layer, wherein the first metal-containing precursor or the second metal-containing precursor is selected from a rare earth metal-containing precursor, a zirconium-containing precursor, a hafnium-containing precursor, a tantalum-containing precursor, or an aluminum-containing precursor; a step of contacting the partial metal adsorption layer with a second metal-containing precursor or a first metal-containing precursor during a second period to form a co-adsorption layer containing the first and second metals; and a step of contacting the co-adsorption layer with a reactant to form a rare earth metal-containing oxide coating. In certain embodiments, the rare earth metal-containing oxide coating comprises about 1 mol% to about 40 mol% of a first metal and about 1 mol% to about 40 mol% of a second metal, and the rare earth metal-containing oxide coating may be a homogeneous mixture of the first metal and the second metal.
[0077] According to various embodiments, the co-deposition of a rare earth metal-containing oxide coating includes a step of performing at least one M1-M2 co-deposition cycle, which includes a step of contacting the surface with a first metal-containing precursor, to form a partially first metal adsorption layer; a step of subsequently contacting the partially first metal adsorption layer with a second metal-containing precursor to form an M1-M2 co-adsorption layer; and a step of contacting the M1-M2 co-adsorption layer with a reactant. As a result of at least one M1-M2 co-deposition cycle, a layer containing a first proportion of the first metal and a second proportion of the second metal may be obtained.
[0078] In some embodiments, the co-deposition of a rare-earth metal-containing oxide coating may further include: performing at least one M2-M1 co-deposition cycle, which includes contacting the surface with a second metal-containing precursor, to form a partial second metal adsorption layer; subsequently, contacting an additional partial metal adsorption layer with a rare-earth metal-containing precursor to form an M2-M1 co-adsorption layer; and contacting the M2-M1 co-adsorption layer with a reactant. As a result of at least one M2-M1 co-deposition cycle, an additional layer may be obtained containing a third proportion of the first metal and a fourth proportion of the second metal, where the third proportion is lower than the first proportion and the fourth proportion is higher than the second proportion.
[0079] The methods according to the embodiments described herein include the steps of selecting a ratio of the number of M1-M2 co-deposition cycles to the number of M2-M1 co-deposition cycles, thereby obtaining a first target mol% of the first metal and a second target mol% of the second metal; and performing a plurality of deposition supercycles, each deposition supercycle further comprising the steps of performing a first number of M1-M2 co-deposition cycles and performing a second number of M2-M1 deposition cycles. According to various embodiments, the step of performing at least one M1-M2 co-deposition cycle may include the steps of: contacting the surface with a rare earth metal-containing precursor for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds; contacting a partially first metal adsorption layer with a second metal-containing precursor for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds; contacting the M1-M2 co-adsorption layer with a reactant for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds; and performing at least one M2-M1 co-deposition cycle. The steps of performing at least one M2-M1 co-deposition cycle may include: contacting the surface with a second metal-containing precursor for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds; contacting an additional partial metal adsorption layer with a rare earth metal-containing precursor for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds; and contacting the M2-M1 co-adsorption layer with the reactant for about 50 milliseconds to about 60 seconds, or for about 1 second to about 60 seconds, or for about 5 seconds to about 60 seconds, or for about 10 seconds to about 60 seconds.
[0080] The following examples are provided to aid in understanding the embodiments described herein and should not be construed as specifically limiting the embodiments described herein and claimed. Any modifications, including the substitution of all currently known or subsequently developed equivalents, and any changes or minor modifications to the scheme in experimental designs, which are within the scope of the embodiments incorporated herein, should be considered within the scope of the embodiments incorporated herein. These examples may be achieved by carrying out the methods described herein.
[0081] Example 1: Mechanical separation within a coating formed by the sequential deposition of rare earth metal oxides and aluminum oxide.
[0082] As shown in the transmission electron microscope image in Figure 4A, the substrate is made of yttrium aluminum oxide (Y x Al y O z The coating was fabricated using sequential ALD technology. A buffer layer was deposited on the substrate surface, followed by 10 cycles of yttrium oxide deposited on the buffer layer, and then 1 cycle of aluminum oxide deposited. The coated substrate was loaded into a processing chamber and exposed to nitrogen trifluoride (NF3) plasma at 450°C for 3,000 processing cycles. Figures 4B and 4C are transmission electron microscope images of the sequentially deposited yttrium aluminum oxide coating on the substrate after exposure to nitrogen trifluoride plasma. As shown, the aluminum oxide layer is mechanically separated from the yttrium oxide layer. When the coating is exposed to plasma, the layer separation becomes greater because the amount of NF3 erosion differs between the YO layer and the AlO layer. Phase separation also occurs in other sequential deposition processes using different metals and / or different number of cycles of first metal vs. second metal (or further metals). For example, Y has a ratio of 5 cycles of Y2O3 to 1 cycle of ZrO2 (5:1 ratio) and a ratio of 5 cycles of Y2O3 to 2 cycles of ZrO2 (5:2 ratio). x Zr y O z Phase separation is observed in the coating.
[0083] Example 2: Y on a substrate using ALD x Zr y O z Co-deposition of coatings
[0084] Yttrium zirconium oxide (Y) as shown in Figure 5A x Zr y O z The coating was co-deposited onto the substrate using ALD according to the embodiments described herein (i.e., M1-M2 and M2-M1 co-deposition cycles were performed). The order of co-deposition can be expressed by the following formula. 180*[2*(1s Y+1s Zr+100ms H2O)+1*(1s Zr+1s Y+100ms H2O)] Therefore, the coating was formed by a ratio of two RE-Zr co-deposition cycles (m=2) to one Zr-RE co-deposition cycle (n=1). In each cycle, each Y precursor and Zr precursor was rhythmically delivered for 1 second, and the reactant H2O was rhythmically delivered for 100 ms. A total of 180 (K=180) supercycles were performed. The ALD reactor was controlled to a temperature of 300°C. The yttrium-containing precursor used to form the film was (CH3Cp)3Y, and the zirconium-containing precursor was Cp-tris(dimethylamino)zirconium. The thickness of the resulting rare-earth metal-containing coating was 50 nm.
[0085] The resulting coating is a single layer of Y2O3-ZrO2 solid solution. x Zr y O z It was a coating. In some compositions, multiple phases may be present. Examples include Y2O3-ZrO2 solid solution, as well as Y2O3, yttria-stabilized zirconia (YSZ), Zr2Y2O7, and Zr3Y4O 12and / or ZrO2. However, co-deposition typically results in a homogeneous mixture of co-deposited metals (here, Y and Zr). Co-deposited coatings, such as those shown in Figure 5A, do not necessarily undergo mechanical interlayer separation like the sequentially deposited coatings prepared in Example 1. In particular, sequentially deposited coatings may not undergo mechanical separation if the cycle ratio between at least two deposited metals is sufficiently low (e.g., 1:1, 2:1, 3:1). This is because the layers deposited by ALD are sufficiently thin and completely interdiffuse when heated. Conversely, if the cycle ratio is, for example, 5 layers of the first metal to 2 layers of the second metal (i.e., 5:2), mechanical separation becomes clearly visible. As a result, ALD deposition of composite metal oxides by sequential deposition techniques generally results in phase separation, with the exception of a few specific M1:M2 ratios. In particular, sequentially deposited composite metal oxide coatings that do not require phase separation include composite metal oxide coatings with a first-to-second metal ratio of 3:1 (e.g., resulting in 75 mol% O, 20 mol% M1, and 5 mol% M2), composite metal oxide coatings with a first-to-second metal ratio of 2:1 (e.g., resulting in 70 mol% O, 20 mol% M1, and 10 mol% M2), and composite metal oxide coatings with a first-to-second metal ratio of 1:1 (e.g., resulting in 65 mol% O, 20 mol% M1, and 15 mol% M2). However, sequentially depositing composite metal oxide coatings with different M1:M2 ratios can result in some degree of phase separation.
[0086] The co-deposited coating shown in Figure 5A has a polycrystalline microstructure as measured by electron diffraction. As shown in Figures 5B and 5C, TEM / EDS line scans show that the chemical composition of the coating is uniform (YZrO) throughout the entire film depth.
[0087] Using Rutherford backscatter / X-ray fluorescence (RBS / XRF) film stoichiometry, it was measured that the atomic concentrations of Y, Zr, and O are constant throughout the film depth. Table 1 shows the atomic concentrations. [Table 1]
[0088] Secondary ion mass spectrometry (SIMS) was performed on the co-deposited coating to evaluate whether the coating contained trace elements (e.g., contaminants diffused from the substrate into the coating). SIMS is a highly sensitive measurement technique capable of detecting metal ion concentrations as low as 1 ppb depending on the element. SIMS measurements showed that none of the following trace elements (Al, B, Ca, Co, Cr, Cu, Fe, Ga, K, Li, Mg, Mn, Na, Ni, Ti) were detected in the co-deposited coating. Thus, the SIMS measurement technique did not detect any of these trace elements in the co-deposited coating. The SIMS data indicates that surface contamination of the co-deposited coating is very low, and even at high temperatures of 300°C, the diffusion of trace elements from the underlying aluminum or other substrates into the co-deposited coating is successfully prevented.
[0089] X-ray diffraction (XRD) was performed to measure the phases within the film. A summary of the results is shown in Table 2. [Table 2]
[0090] Example 3: Comparison of YZrO coatings created using different techniques
[0091] Several samples were prepared using various ALD deposition methods. Samples A, B, D, and F were prepared by sequentially depositing Y2O3 and ZrO2 at various cycle ratios. The sequentially deposited layers were subsequently annealed to promote inter-metallic interdiffusion. Sample C was prepared by the same co-deposition method as described in Example 2, as follows: 180*[2*(1s Y+1s Zr+100ms H2O)+1*(1s Zr+1s Y+100ms H2O)]. Sample E was a pure ZrO2 coating deposited by ALD, and samples G and H were also pure Y2O3 coatings deposited by ALD.
[0092] As shown in Table 3, samples A-F containing a combination of Y and Zr or pure ZrO2 showed superior performance in all aspects compared to samples G and H, which were coated with pure Y2O3. For example, the pure Y2O3 coating had a microstructural change layer (e.g., degradation or erosion due to fluorine) of about 20 nm to 40 nm on its surface, while all other samples had 0 nm. The depth of fluorination in the pure Y2O3 was at least twice as deep as the depth of fluorination in all other samples (i.e., 100 nm). The maximum fluorine concentration in samples G and H, which were pure Y2O3, was higher than in all other samples, and the total amount of fluorine diffused into the pure Y2O3 coating was far greater than in all other samples.
[0093] Samples A, B, and F did not have a microstructure change layer on their surface, and among them, sample B, with a Y2O3 to ZrO2 cycle ratio of 2:1, showed the deepest fluorination. Sample B also had the lowest maximum fluorine concentration and the lowest total amount of fluorine diffused into the coating among samples A, B, and F. However, in the case of sample D, where the sequential deposition cycle ratio was 5 cycles of Y2O3 to 2 cycles of ZrO2, the resulting coating was fluorinated throughout its entire depth. The maximum fluorine concentration in sample D was 15%, and the total amount of fluorine diffused into the coating was approximately 323%*nm. Without being bound by any particular theory, it is thought that with a sequential deposition cycle ratio of 5:2, the coating underwent mechanical (phase) separation between the Y2O3 layer and the ZrO2 layer. As a result, the function of metal interdiffusion to form solid solutions was affected, creating voids into which fluorine could diffuse. It is also thought that mechanical interlayer separation occurs as the number of Y2O3 and ZrO2 cycles increases (e.g., 6:3, 7:2, 10:4, etc.) to form coatings with specific mass ratios of Y to Zr. The total amount of fluorine in Sample 2, a 5:2 YZrO coating deposited by sequential ALD within a YZrO coating, is much higher than in the coatings of Samples A, B, and F. Without being bound by any particular theory, the difference in the total amount of fluorine among Samples A, B, D, and F is thought to be due to ineffective mixing of the layers. The layers in which this ineffective mixing occurs are, for example, the relatively thick 5-cycle Y2O3 layer and the 2-cycle ZrO2 layer. Other deposited samples with coatings created by 1:1 (Sample F) and 2:1 (Sample B) sequential deposition methods are expected to have the best mixing among Samples A, B, D, and F due to the much thinner layers and efficient interdiffusion. Sample A, with a Y2O3 to ZrO2 cycle ratio of 3:1, is also expected to have a higher maximum fluorine concentration and total fluorine content than Sample F (1:1) and Sample B (2:1).
[0094] As described above, the co-deposition of Y and Zr metals according to the embodiments of this specification eliminates mechanical separation between separate layers containing Y and Zr. Figure 6A is a TEM image of the pure yttrium oxide coating from sample G after exposure to a fluorine-containing plasma. Figure 6B is a TEM image of the co-deposited yttrium zirconium oxide coating from sample C after exposure to a fluorine-containing plasma. As shown in Figure 6A, the pure yttrium oxide coating suffered microstructural degradation, while the co-deposited YZrO coating shown in Figure 6B did not suffer this type of degradation.
[0095] Without being bound by any particular theory, the metal co-deposition process is thought to result in good mixing of the metals (i.e., homogeneous mixing), eliminating voids within the co-deposited coating and thereby forming a solid solution of metal oxides. The molar ratio of Y to Zr in sample C (i.e., co-deposited) is comparable to that of sample D (i.e., 5:2, Y:Zr, sequential deposition). However, as shown in Table 3 and the TEM / EDS line scans in Figures 7A and 7B and 8A and 8B, the co-deposited coating of sample C is fluorinated only to a depth of approximately 30 nm, while in sample D, fluorination extends to the entire depth. Sample C also has a lower maximum fluorine concentration than sample D, and the total amount of fluorine diffusing within the co-deposited coating (i.e., the integral of the fluorine curve in the EDS line scan) is halved compared to the 5:2 sequential deposition coating of sample D. [Table 3]
[0096] The above description provides numerous specific details, such as examples of specific systems, components, and methods, in order 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 can be carried out without such specific and detailed descriptions. In other examples, well-known components or methods are not described in detail or are presented in simple block diagram form to avoid unnecessarily obscuring the invention. Thus, the specific and detailed descriptions are merely illustrative. Certain embodiments may differ from these illustrative descriptions but are still considered to fall within the scope of the present invention.
[0097] Throughout this specification, whenever the terms "in a particular embodiment" or "in one embodiment" are used, it means that any specific configuration, structure, or characteristic described in relation to that embodiment is included in at least one embodiment. Therefore, even if the phrases "in a particular embodiment" or "in one embodiment" appear in various places throughout this specification, they do not necessarily all refer to the same embodiment. Furthermore, the term "or" is intended to mean inclusive, not exclusive. Where the terms "about" or "approximately" are used in this specification, it is intended that the presented nominal values are accurate within a range of ±10%.
[0098] Although the operations of the methods described herein are shown and described in a specific order, the order of the operations of each method may be changed so that certain operations are performed in reverse order, or some operations are performed at least partially in parallel with others. In another embodiment, instructions or suboperations of different operations may be performed intermittently and / or alternately.
[0099] It should be understood that the above description is illustrative and not limiting. By reading and understanding the above description, many other embodiments will become apparent to those skilled in the art. Therefore, the scope of the invention should be determined by reference to the appended claims, together with the entire scope of equivalents to which such claims are entitled.
Claims
1. Articles, The main unit and The main body surface is equipped with a rare earth metal-containing oxide coating. The rare earth metal-containing oxide coating comprises 10 mol% to 40 mol% of a first metal and 10 mol% to 40 mol% of a second metal, wherein the first metal is a rare earth metal, and the second metal is selected from the group consisting of hafnium and tantalum. Rare earth metal-containing oxide coatings are articles containing a homogeneous mixture of a primary metal and a secondary metal.
2. The article according to claim 1, wherein the rare earth metal-containing oxide coating has a thickness of 5 nm to 10 μm.
3. Rare earth metal-containing oxide coatings contain 20 mol% to 85 mol% oxygen. The articles are components of a processing chamber selected from the group consisting of chamber walls, shower heads, nozzles, plasma generation units, high-frequency electrodes, electrode housings, diffusers, and gas lines, and / or The article according to claim 1, wherein the main body comprises a material selected from the group consisting of aluminum, steel, silicon, copper, and magnesium.
4. The first metal includes rare earth metals selected from the group consisting of yttrium, erbium, lanthanum, lutetium, scandium, gadolinium, samarium, and dysprosium, or The first metal contains yttrium, and the rare earth metal-containing oxide coating contains zirconium in a concentration of 1 mol% to 40 mol%, or The rare earth metal-containing oxide coating contains Y w Zr x Hf y O z 、 Er w Zr x Hf y O z 、 Y v Er w Zr x Hf y O z 、 Y x Hf y O z 、 Er x Hf y O z 、 Y x Ta y O z 、 Er x Ta y O z 、 Y w Ta x Hf y O z 、 Er w Ta x Hf y O z and Y v Er w Ta x Hf y O z The article according to claim 1, comprising a composition selected from the group consisting of
5. The article according to claim 1, further comprising a buffer layer on the surface of the main body, wherein a rare earth metal-containing oxide coating covers the buffer layer, and the buffer layer comprises a material selected from the group consisting of aluminum oxide, silicon oxide, and aluminum nitride.
6. A method comprising the step of co-depositing a rare earth metal-containing oxide coating onto the surface of an article using atomic layer deposition, The process of co-depositing a rare earth metal-containing oxide coating is, A step of forming a partially metal adsorbed layer containing a first metal (M1) or a second metal (M2) by bringing the surface into contact with a first metal-containing precursor or a second metal-containing precursor during a first period, wherein the first metal-containing precursor is a rare earth metal precursor, and the second metal-containing precursor is selected from the group consisting of a hafnium-containing precursor and a tantalum-containing precursor. A step of bringing a partially metal-adsorbed layer into contact with a second metal-containing precursor or a first metal-containing precursor during the second period to form a co-adsorbed layer containing a first metal and a second metal, wherein the first metal is different from the second metal. The process includes the step of bringing a co-adsorption layer into contact with a reactant to form a rare earth metal-containing oxide coating. The rare earth metal-containing oxide coating contains 10 mol% to 40 mol% of the primary metal and 5 mol% to 40 mol% of the secondary metal. The concentration of the first metal is higher than the concentration of the second metal. The rare earth metal-containing oxide coating method involves a homogeneous mixture of a primary metal and a secondary metal.
7. The process of co-depositing a rare earth metal-containing oxide coating is, A step of performing at least one M1-M2 codeposition cycle, A step of bringing the surface into contact with a first metal-containing precursor to form a partially metal-adsorbed layer, Next, the partially metal-adsorbed layer is brought into contact with a second metal-containing precursor to form an M1-M2 co-adsorbed layer. The process includes a step of bringing the M1-M2 co-adsorption layer into contact with a reactant, The method according to claim 6, wherein a layer containing a first proportion of a first metal and a second proportion of a second metal is obtained by at least one M1-M2 codeposition cycle.
8. The process of co-depositing a rare earth metal-containing oxide coating is, A step of performing at least one M2-M1 codeposition cycle, A step of bringing the surface into contact with a second metal-containing precursor to form a second partial metal adsorption layer, Next, the second partial metal adsorption layer is brought into contact with the first metal-containing precursor to form an M2-M1 co-adsorption layer. The process further includes a step of bringing the M2-M1 co-adsorption layer into contact with a reactant, The method according to claim 7, wherein at least one M2-M1 codeposition cycle yields an additional layer containing a third proportion of the first metal and a fourth proportion of the second metal, the third proportion being lower than the first proportion and the fourth proportion being higher than the second proportion.
9. A step of selecting the ratio of the first number of M1-M2 co-deposition cycles to the second number of M2-M1 co-deposition cycles, wherein as a result of the selection, a first target mol% of the first metal and a second target mol% of the second metal are obtained. The method according to claim 8, further comprising the step of performing a plurality of sedimentation supercycles, each sedimentation supercycle comprising the step of performing a first number of M1-M2 co-sedimentation cycles and the step of performing a second number of M2-M1 co-sedimentation cycles.
10. The step of performing at least one M1-M2 co-deposition cycle is: A step of bringing the surface into contact with a first metal-containing precursor for 50 milliseconds to 60 seconds, A step of bringing a partially metal-adsorbed layer into contact with a second metal-containing precursor for 50 milliseconds to 60 seconds, The process includes the step of bringing the M1-M2 co-adsorption layer into contact with the reactant for 50 milliseconds to 60 seconds. The step of performing at least one M2-M1 co-deposition cycle is: A step of bringing the surface into contact with a second metal-containing precursor for 50 milliseconds to 60 seconds, The process involves contacting an additional partial metal adsorption layer with the first metal-containing precursor for 50 milliseconds to 60 seconds, The method according to claim 8, comprising the step of bringing the M2-M1 co-adsorption layer into contact with a reactant for 50 milliseconds to 60 seconds.
11. The first metal-containing precursor and the second metal-containing precursor are independently: cyclopentadienyl precursor, tris(methylcyclopentadienyl)yttrium((CH3Cp)3Y), tris(butylcyclopentadienyl)yttrium, tris(cyclopentadienyl)yttrium, tris(ethylcyclopentadienyl)yttrium, tris-methylcyclopentadienylerbium(III)(Er(MeCp)3), tris(butylcyclopentadienyl)erbium(III); amidinate precursor, tris(N,N'-diisopropylformamidinate)yttrium, tris(2,2,6,6-tetramethylheptane-3,5-diona The method according to claim 6, selected from the group consisting of yttrium, tris(bis(trimethylsilyl)amide)lanthanum, amide precursors, erbium boranamide (Er(BA)3), β-diketnate precursors, erbium(III), tris(2,2,6,6-tetramethyl-3,5-heptanedionate), tris(dimethylamino)(cyclopentadienyl)zirconium, tetrakis(dimethylamide)zirconium, tetrakis(diethylamide)zirconium, tetrakis(N,N'-dimethylformamidinate)zirconium, tetra(ethylmethylamide)hafnium, and pentakis(dimethylamide)tantalum.
12. The method according to claim 6, further comprising the step of contacting a co-adsorption layer with a third precursor to adsorb a third metal, and then contacting the co-adsorption layer with a reactant, wherein the third precursor is selected from the group consisting of yttrium precursor, erbium precursor, zirconium precursor, hafnium precursor, silicon precursor, tantalum precursor, lanthanum precursor, lutetium precursor, scandium precursor, gadolinium precursor, samarium precursor, and dysprosium precursor.
13. The method according to claim 6, further comprising the steps of depositing a buffer layer on the surface of an article by atomic layer deposition and co-depositing a rare earth metal-containing coating on the buffer layer, wherein the buffer layer comprises at least one of aluminum oxide, silicon oxide, or aluminum nitride.
14. A method comprising the step of co-depositing a rare earth metal-containing oxide coating onto the surface of an article using atomic layer deposition, The process of co-depositing a rare earth metal-containing oxide coating is, A step of performing at least one co-injection cycle, A step of forming a co-adsorbent layer by bringing the surface into contact with a mixture of a first precursor and a second precursor during a first period, wherein the first precursor is a rare earth metal precursor, and the second precursor is selected from the group consisting of a hafnium-containing precursor and a tantalum-containing precursor. The process includes a step of contacting the co-adsorption layer with an oxygen-containing reactant to form a rare earth metal-containing oxide coating, The rare earth metal-containing oxide coating comprises 10 mol% to 40 mol% of a first metal and 10 mol% to 40 mol% of a second metal, wherein the first metal is a rare earth metal, and the second metal is selected from the group consisting of hafnium and tantalum. The rare earth metal-containing oxide coating method involves a homogeneous mixture of a primary metal and a secondary metal.
15. A method comprising the step of depositing a rare earth metal-containing oxide coating on the surface of an article using atomic layer deposition, The process of depositing a rare earth metal-containing oxide coating is as follows: The process involves bringing the surface into contact with a first precursor during the first period to form a first metal adsorption layer, A step of bringing a first metal adsorption layer into contact with a reactant to form a first metal oxide layer, The process involves bringing the first metal layer into contact with the second precursor during the second period to form a second metal adsorption layer, A step of bringing a second metal adsorption layer into contact with a reactant to form a second metal oxide layer, The process includes the step of forming a rare earth metal-containing oxide coating from a first metal oxide layer and a second metal oxide layer. The rare earth metal-containing oxide coating comprises 10 mol% to 40 mol% of a first metal and 10 mol% to 40 mol% of a second metal, wherein the first metal is a rare earth metal and the second metal is selected from the group consisting of hafnium and tantalum.
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