A substrate having a fluorinated yttrium coating, and methods of manufacturing and using the substrate

Abstract

Described are substrates comprising at least two coatings, one coating on the high aspect ratio surface and a second coating on the non-high aspect ratio surface, having a fluorinated exterior surface; methods of making these coatings; and substrates, surfaces, devices, and device parts comprising the coatings.

Description

Technical Field

[0001] This specification relates to a substrate comprising at least two coatings, one coating on a high aspect ratio surface and a second coating on a non-high aspect ratio surface, having a high aspect ratio surface and a non-high aspect ratio surface with a fluorinated outer surface; a method of manufacturing these coatings; and substrates, surfaces, devices, and device components comprising the coatings.

Background Art

[0002] Methods of manufacturing semiconductors and ultra-small electronic devices require various processing steps involving highly reactive process materials, particularly plasma, acids, accelerated ions, etching solutions (e.g., halogens and halogenated materials), corrosive materials, cleaning agents, and the like.

[0003] Exemplary processes performed in semiconductors and ultra-small electronic devices include, in particular, ion implantation processes (e.g., “doping” processes), etching processes that may use plasma or halogen materials, cleaning processes, and deposition processes, each of which may involve the use of reactive, corrosive, or high-energy process materials within a “process chamber”. Each of these types of processes is performed inside a process chamber that houses a workpiece (e.g., “substrate”) and process materials. The process chamber defines the process chamber and the members inside the process chamber or members associated with the chamber, and also includes various structures and components necessary for operation (sometimes abbreviated herein as “process chamber components” or “process tool components”). These process chamber components include chamber walls, flow conduits (e.g., flow lines, flow heads, pipes, tubes, etc.), electrical components (e.g., electrodes), fasteners, trays, supports, and other structures and devices used to support the workpiece or to deliver, contain, act on, or otherwise contact the reactive process materials used within the process chamber.

[0004] To be used as part of a process chamber, the process tool components should be resistant to the reactive process materials that will be used within the process chamber. The process chamber components should not degrade or be damaged in a manner that would generate debris or particulates that could contaminate the workpiece being incorporated into and processed by the process being performed, particularly upon contact with the process materials.

[0005] Process chamber components used in semiconductor processing equipment for manufacturing semiconductors and ultra-small electronic devices are often made of solid materials ("substrates" or "bases"), such as metals (e.g., stainless steel, aluminum alloys that may optionally be anodized, tungsten), minerals, or ceramic materials. The substrate is typically coated with a protective layer that is more resistant to reactive process materials than the substrate material. In the past, such protective coatings have typically been placed on the substrate surface by various useful methods, typically anodization (e.g., to produce anodized aluminum), spray coating, or deposition methods, such as physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or a process that is a modification or derivative of one of them.

SUMMARY OF THE INVENTION

[0006] The following description relates to a coated substrate having at least two different coatings on the surface of the substrate, each coating containing or derived from yttrium oxide, and the outer surface of the coated substrate being fluorinated, as well as related processes and methods of using the coated substrate.

[0007] The two different coatings are applied to different portions of the substrate surface including three-dimensional high aspect ratio features to produce a protective coating. One coating is non-directional and is deposited on the surface of the substrate (referred to as the "high aspect ratio surface") that can be difficult to coat in a way that is only effective in depositing material at the "aiming" position of the substrate using various deposition methods. This coating of the combination may be applied by non-directional atomic layer deposition techniques and may be effective in depositing material on the surface of the three-dimensional high aspect ratio features of the substrate, i.e., the high aspect ratio surface.

[0008] Portions of the substrate surface other than the surface of the three-dimensional high aspect ratio feature, i.e., the "non-high aspect ratio surface", can be coated with different coatings. This coating, sometimes referred to herein as a "partial" coating, can be applied to the surface of the substrate that requires protection from a large amount of process chemicals during use of the substrate. The coating can be applied by a directional "aimed" deposition method.

[0009] Each coating includes, or may be derived from, a deposited layer containing yttrium oxide ("yttria" or "Y2O3"). One or more surfaces of the coating can be treated by a fluorination process and at least partially fluorinated after deposition to form yttrium fluoride ("YF3") or fluorinated yttrium oxide ("YOF").

[0010] In one aspect, the present invention relates to a coated substrate having at least two coatings. The substrate includes a high aspect ratio surface of a feature having an aspect ratio of at least 2:1, and a non-high aspect ratio surface. The coatings include a first yttrium oxide coating covering at least the high aspect ratio surface; a second yttrium oxide coating covering at least the non-high aspect ratio surface; and fluorinated yttrium oxide in the outer portions of the coatings located on the high aspect ratio surface and the outer portions of the coatings located on the non-high aspect ratio surface.

[0011] In another aspect, the present invention relates to a method of coating a substrate including a high aspect ratio surface and a non-high aspect ratio surface. The method includes depositing an atomic layer deposition yttrium oxide coating on at least the high aspect ratio surface; depositing a non-atomic layer deposition yttrium oxide coating on at least the non-high aspect ratio surface before or after depositing the atomic layer deposition yttrium oxide coating; and fluorinating the exposed surfaces of the coatings on one or both of the high aspect ratio surface and the non-high aspect ratio surface.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2A

Figures 2B-C

Figures 2D-E

Figures 2F-G

Modes for Carrying Out the Invention

[0013] All the figures are schematic and not to scale.

[0014] The following description relates to a coated substrate having at least two coatings on the surface of a substrate having a high aspect ratio surface and a non-high aspect ratio surface. Each coating may contain yttrium combined with oxygen, fluorine, or both oxygen and fluorine. The coating can include a deposited yttrium oxide layer, which is derived therefrom and optionally fluorinated, and even if a part or all of the yttrium oxide of the coating is fluorinated, it may be generally referred to as a "yttrium oxide coating" in this specification. This specification also relates to a process apparatus including a substrate including the use of two or more different yttrium oxide coatings as protective coatings on the surface of a substrate including a high aspect ratio surface, and a combination of the described yttrium fluoride coatings.

[0015] The substrate described includes a combination of two or more yttrium oxide coatings. One coating is arranged to coat the surface of three-dimensional high aspect ratio features of the substrate. This coating is applied, for example, by an atomic layer deposition technique, a multi-directional coating method effective for depositing a layer of yttrium oxide-containing material on surfaces that cannot be easily coated by other coating methods such as "aiming" coating techniques. Coatings that coat the high aspect ratio features of the substrate, particularly coatings that deposit on high aspect ratio surfaces such as the surface of small circular holes in a flow distribution device (e.g., a showerhead) having small dimensions, need not be particularly thick. In those situations, the coating preferably can have a thickness small enough so as not to unduly affect the size or shape of the structure and, in particular, to avoid having an undesirable effect on the performance characteristics (e.g., flow characteristics) of the structure.

[0016] According to certain exemplary methods and coated substrates, the coating deposited on the surface of three-dimensional high aspect ratio features of the substrate (the "high aspect ratio surface") may be in the form of a "sealing coating" that coats the entire surface of the substrate. In an exemplary embodiment, the sealing coating coats at least 95, 98 or 99 percent of the total amount of the surface area of the substrate.

[0017] Another coating of the described coating combinations may be a coating that covers a portion of the substrate that is not part of the high aspect ratio features of the substrate, also referred to herein as the "non-high aspect ratio surface". This coating can be applied to the surface of the substrate that is exposed to reactive chemicals ("process materials" or "process chemicals") that can physically or chemically degrade the surface of the substrate during use. In some embodiments, the coating of the non-high aspect ratio surface is performed using directional techniques, i.e., "aimed" type techniques. Examples of useful techniques include, but are not limited to, physical vapor deposition techniques (e.g., sputtering) and chemical vapor deposition techniques (e.g., plasma enhanced chemical vapor deposition). In some embodiments, the coating deposited by the aiming technique also coats a portion of the high aspect ratio surface. In some embodiments, the combination of coatings applied by the aiming technique and the multi-directional technique ensures that both the high aspect ratio surface and the non-high aspect ratio surface are completely coated in a manner that is difficult to achieve by the use of the aiming technique alone and is more efficient than the multi-directional technique alone.

[0018] The described coating combinations include two different chemically inert protective coatings combined to coat different surfaces of a substrate, protecting those surfaces and preventing or reducing degradation of the substrate surface that would be caused by direct contact between the substrate surface and process materials. The coating combinations have a fluorinated outermost surface in both high aspect ratio surfaces and non-high aspect ratio surfaces. In some embodiments, the outermost surface of the coating combination can be deposited entirely by a multidirectional technique. In other embodiments, the outermost surface of the coating combination can have portions deposited by a multidirectional technique and portions deposited by a directed technique. In an exemplary use, these two types of yttrium oxide coating combinations can function as protective fluorinated coatings on various surfaces of a substrate that are chemically resistant to reactive chemicals (process materials) used in methods of processing semiconductors or microelectronic devices.

[0019] The described yttrium oxide coating combinations can be useful for protecting substrates that include surface features where the morphology is three-dimensional, particularly substrates that include one or more three-dimensional surface features that exhibit a high aspect ratio. As an example, one of the coatings in a coating combination applied to a substrate can be deposited on the surface of one or more high aspect ratio features of the substrate. These can include various three-dimensional structures that extend below the main surface (e.g., the "top", "dominant", or "major" surface) of the substrate and form or include substrate sub-surfaces that are protected, safeguarded, partially blocked, or otherwise have a low level of accessibility for depositing a coating on the surface.

[0020] The "main" surface can be the surface of a substrate that covers a substantial or dominant amount of the substrate and does not define features having a high aspect ratio. The main surface may be considered to be the "upper" or "lower" surface of a substantially two-dimensional structure, such as a planar or curved sheet or plate. The main surface may be a substantially planar or curved surface that extends across a length and a width, different from any three-dimensional structures, such as holes, channels, pores, grooves, etc., that also exist as part of the substrate, however, this planar or curved surface may have boundaries (ends) that connect to or define the boundaries of one or more three-dimensional structures, such as holes, channels, pores, grooves, etc., that can define and include high aspect ratio surfaces. The main surface will include surfaces that are not part of high aspect ratio features and will include "non-high aspect ratio" surfaces.

[0021] Surfaces that define three-dimensional structures, sometimes also referred to as "secondary surfaces", are surfaces that are formed within or disposed under the main surface as part of the substrate. These "secondary" surfaces are more difficult for materials to contact during a deposition process and for materials to be deposited as coating materials. The secondary surface may be a surface that defines the sidewalls or bottom structure of a three-dimensional structure, such as a hole, depression, groove or channel, formed within and extending under the main surface. The three-dimensional structure including the secondary surface can have a depth dimension (under the upper (main) surface of the substrate) equal to or greater than the cross-sectional (e.g., width) dimension of the structure, which is characteristic of a "high aspect ratio" feature, in which case the surface of the three-dimensional structure can be referred to as a "high aspect ratio" surface.

[0022] For example, to form a protective coating on a substrate surface containing a three-dimensional structure defined by a main surface and a secondary surface, and for the coating to uniformly cover the surface of the substrate (main surface and secondary surface), the described coating combinations include one coating deposited on the surface of a three-dimensional structure including a high aspect ratio surface that is part of a high aspect ratio structure, and a second coating deposited on a surface that is not part of the high aspect ratio structure, such as a second coating deposited on one or more main surfaces or non-high aspect ratio surfaces of the substrate.

[0023] The described coatings can include three-dimensional surface features including three-dimensional surfaces having a high aspect ratio, and can desirably include a protective (e.g., chemically inert, non-reactive) coating, and can be included on any surface or substrate. A combination of coatings can be formed on a substrate to form a "coated article" (e.g., a coated process tool part), and the coating is applied to the surface of the substrate in a solid, continuous or semi-continuous form, resulting in a chemically resistant barrier coating on the substrate surface. The coating can be applied to high aspect ratio surfaces, non-high aspect ratio surfaces, and optionally only to the entire surface or a portion of the substrate. For example, a substrate in the form of a plate having apertures, including two opposing faces and apertures extending along the thickness direction of the plate, can be coated on the surface of the holes and additionally on one face of the plate, and optionally on both opposing side faces of the plate.

[0024] Examples of substrates include parts of process chambers ( "process tool parts") used to manufacture semiconductor materials, microelectronic devices, etc. The coatings of the present specification deposited on the surface of the substrate will be exposed to process chemicals (reactive chemicals such as halides, plasmas, acids, etc.) during the use of the coated substrate of the process tool. Since it is resistant to damage (physical or chemical degradation) due to contact with process chemicals, the described coatings can be used on the surface of process tool parts of process chambers that will contain these and other process materials, reducing degradation and the formation of particles or debris that occur on the substrate surface during the use of the process tool parts.

[0025] Atomic layer deposition (ALD) techniques for depositing a coating on the surface of a substrate are particularly useful for applying a uniform conformal coating on surfaces having two-dimensional or three-dimensional features, and in particular on high aspect ratio surfaces, including three-dimensional structures that may have small or some surfaces that cannot be reached by other types of deposition methods and that may be characteristic of structures considered to exhibit a high aspect ratio.

[0026] Atomic layer deposition techniques are performed by placing the substrate within an environment of a non-directional, cloud-like gaseous material that will contact and deposit on the surface of the substrate. The non-directional, cloud-like chemical material deposits as a highly conformal coating of uniform thickness on the entire surface of the substrate exposed to the deposition environment. Using atomic layer deposition techniques, materials can be deposited on surfaces that are not accessible with "line-of-sight" deposition techniques (deposition techniques that deposit material only on surfaces that are in a straight line of an unobstructed path (or "line-of-sight") between the surface and the source of the material to be deposited on the surface). Thus, atomic layer deposition techniques are useful for depositing a coating on the entire surface of a three-dimensional substrate, including the surfaces of three-dimensional structures and in particular the surfaces of high aspect ratio features (high aspect ratio surfaces) of the substrate.

[0027] Exemplary high aspect ratio surfaces include holes (including holes having narrow pores and a depth greater than the size of the pores), channels, depressions, internal plenums, serpentine or helical paths, continuous cellular foams or matrices, and the surfaces of porous membranes, scrims or fabrics. Exemplary substrate surfaces may include features having an aspect ratio of at least 2:1, 5:1, 10:1, 15:1, 20:1, 30:1, 40:1, 50:1, 100:1, 200:1, or even 500:1. In particular, this includes holes, apertures or depressions having a depth (e.g., thickness) and a width (e.g., diameter), where the aspect ratio is defined as depth to width and may be at least 20:1, 50:1, 100:1, 200:1, or even 500:1, and the size of the holes, apertures or depressions on the surface is relatively small, e.g., less than 2 millimeters, e.g., less than 1 millimeter or less than 0.5 millimeter. Thus, as used herein, "high aspect ratio surface" refers to a surface feature where the ratio of depth (e.g., thickness) to width (e.g., diameter) is at least 2:1, 5:1, 10:1, 15:1, 20:1, 30:1, 40:1, 50:1, 100:1, 200:1, or even 500:1. As used herein, "non-high aspect ratio surface" refers to a surface that is not a high aspect ratio surface.

[0028] A coating formed by atomic layer deposition (also referred to herein as an "atomic layer deposition coating") may typically be formed to coat the entire exposed surface of a substrate (including the major surface different from the three-dimensional high aspect ratio surface) during a single deposition process, although this is not necessarily the case. When depositing an atomic layer deposition coating on the entire surface of a substrate including the entire surface of three-dimensional features exhibiting a high aspect ratio and all others (non-high aspect ratio surfaces), the coating may be referred to herein as a "sealing coating".

[0029] According to an exemplary method of forming a yttrium oxide coating on a surface of a substrate including the surface of a three-dimensional high aspect ratio feature of the substrate, an atomic layer deposition technique may be used to dispose a non-fluorinated yttrium oxide precursor coating on the substrate surface including the three-dimensional high aspect ratio feature of the substrate. Yttrium oxide (Y2O3, also known as "yttria") is prepared from and contains yttrium and oxygen in a relative amount (atoms) of about 2:3 (yttrium:oxygen).

[0030] In addition to yttrium oxide, the yttrium oxide coating can contain other metals or metal oxides, either chemically distinct from yttrium oxide or chemically bonded thereto. For example, the yttrium oxide coating can contain a metal such as aluminum, zirconium, titanium, cerium or erbium or an oxide of one of these metals such as aluminum oxide, zirconium oxide, titanium oxide, cerium oxide or erbium oxide. In an exemplary form, the yttrium oxide coating can be a composite of yttrium oxide and another non-yttrium metal oxide such as aluminum oxide. The composite material contains both of the two different chemical materials in their respective molecular oxide forms as a "composite" of two metal oxides. During the fluorination process, fluorine binds to yttrium oxide to form fluorinated yttrium oxide, but the non-yttrium oxide (e.g., aluminum oxide) material of the composite is typically not fluorinated.

[0031] Methods for forming yttrium oxide coatings by atomic layer deposition are known. See, for example, U.S. Patent Publication No. 2018 / 0202047. By way of an exemplary method, a yttrium oxide coating can be deposited as a single layer of a desired thickness or as multiple layers that together form a coating of a desired total thickness. Generally, by way of non-limiting example, the thickness of a single deposited layer of yttrium oxide coating can range from less than 1 nanometer to 2 - 3 or several nanometers, such as about 0.1, 0.5, 1, 2, 5, or 10 nanometers, up to tens or hundreds of nanometers, such as up to 50, 100, 500, 600, 800, or 900 nanometers (0.9 microns) or more. One or more layers can be applied to produce a yttrium oxide coating of a desired total thickness, which can range from 1, 5, or 10 nanometers up to 100, 500, or 1000 nanometers (1 micron).

[0032] Examples of atomic layer deposited yttrium oxide coatings may contain, consist of, or consist essentially of yttrium oxide. Other examples may contain, consist of, or consist essentially of yttrium oxide and one or more other metal oxides, such as aluminum oxide. A material or structure that consists essentially of one or a combination of components is considered to be a material or structure that contains the recited component or combination of components and other materials in an amount less than a trace, such as components other than the recited component or combination of components that are less than 3, 1, 0.5, or 0.1 weight percent of the recited component or combination of components.

[0033] By way of an exemplary method, the yttrium oxide coating may be deposited as a plurality of deposition layers each having a very small thickness, e.g., on the molecular, atomic or monolayer scale, or greater. A plurality of individual deposition layers may be deposited to produce a coating of a desired total thickness. By these exemplary methods, the precursor yttrium oxide coating can contain yttrium oxide alone or in combination with another non-yttrium oxide metal oxide. The non-yttrium oxide metal oxide may be deposited as a plurality of layers of non-yttrium oxide material disposed between the individual yttrium oxide layers. The thickness of the individual layers (of yttrium oxide, metal oxides other than yttrium oxide, or combinations thereof) may range from a desired thickness, e.g., less than 1 nanometer to 2 - 3 or several nanometers, e.g., about 0.1, 0.5, 1, 2, 5 or 10 nanometers or more. One or more layers (of yttrium oxide, metal oxides other than yttrium oxide, or combinations thereof) may be applied to produce a yttrium oxide coating of a desired total thickness, which may range from 1, 5 or 10 nanometers up to 100, 500 or 1000 nanometers (1 micron).

[0034] In addition to the coating applied to the surface of the high aspect ratio features of the substrate, the coated substrate described includes an additional coating deposited on surfaces other than the surface of the high aspect ratio features, i.e., the additional coating is more substantially flat or only slightly curved and covers other (non-high aspect ratio) surfaces that are not part of the high aspect ratio features. In some embodiments, however, the additional coating can cover at least some portion of the high aspect ratio surface. The additional coating is sometimes referred to as a "partial" coating in that when applied to the high aspect ratio surface, it often does not completely, uniformly or evenly coat the high aspect ratio surface, and this additional coating can be selectively applied to the surface of the substrate that particularly requires a relatively high level of chemical resistance during use of the substrate. For example, the partial coating may be applied to the surface of the substrate that is in contact with a large amount of process chemicals during use inside a process chamber used to process semiconductors or microelectronic devices. The partial coating can have a greater thickness than the coating applied to the surface of the high aspect ratio features (applied by atomic layer deposition), and in the portion of the substrate surface that will be exposed to a high level of process chemicals during use, it will result in an increased resistance to contact between the underlying substrate surface and the process chemicals.

[0035] The partial coating is a flat or curved surface and can be produced by a method useful for producing a relatively thicker coating on a surface that does not exhibit a high aspect ratio. The partial coating may be produced by a deposition technique that deposits material by a directional technique, i.e., a "targeted" type technique, which does not necessarily deposit the material completely, uniformly or evenly on the surface of the high aspect ratio features of the substrate, such as the "sub-surface" described herein. Examples of useful techniques include, but are not limited to, physical vapor deposition techniques (e.g., sputtering), chemical vapor deposition techniques (e.g., plasma enhanced chemical vapor deposition).

[0036] The partial coating can be formed on the non-high aspect ratio surface of the substrate by disposing a non-fluorinated yttrium oxide coating of a desired thickness on the substrate surface. Optionally, the coating can then be fluorinated to cause fluorination of a portion of the coating. The coating contains yttrium oxide alone or in combination with another (non-yttrium oxide) metal oxide. The fluorination step converts at least a portion of the yttrium oxide to yttrium oxyfluoride (YOF) or yttrium fluoride (YF3), resulting in the formation of a fluorinated yttrium oxide coating.

[0037] The partial coating can have a thickness that provides a high degree of chemical resistance to the substrate, particularly on the non-high aspect ratio major surface that will be exposed to a large amount of process chemicals during use of the substrate. Exemplary thicknesses can be at least 1 micron, for example, 1, 2, 5, or 10 microns up to a thickness of 10, 20, 25, 50, or 100 microns.

[0038] Optionally, according to an exemplary method and coating, the substrate surface can be coated with an intermediate layer (also known as a "buffer layer") that will improve the performance of the described coating combination before depositing yttrium oxide as a precursor coating. The buffer layer can be included on the substrate surface to prevent physical damage to the yttrium oxide coating that may be caused by thermal stresses that occur during subsequent processes, such as the fluorination process. The buffer layer can be effective in improving the ability of the yttrium oxide precursor coating to be processed at high temperatures by the fluorination process without causing cracking of the yttrium oxide layer due to stresses caused by the high processing temperatures of the fluorination process, such as temperatures exceeding 300 degrees Celsius during a fluoroannealing process. The buffer layer can be particularly useful when the substrate is a metal, such as aluminum or an aluminum alloy.

[0039] The buffer layer may be any layer that is effective in reducing or preventing the unwanted physical effects of the thermal stress that the deposited yttrium oxide precursor coating undergoes, preferably effective in preventing cracks or other physical damage to the deposited yttrium oxide coating from occurring during the fluoroannealing process. The composition, thickness, and method of manufacturing the buffer layer may be any that are useful for manufacturing an effective buffer layer. Examples of buffer layers may be made of ceramic materials such as metal oxides, for example, aluminum oxide, titanium oxide, zirconium oxide, etc. Exemplary thicknesses may range from 25 to 300 nanometers, such as 50 to 200 or 250 nanometers. The exemplary buffer layer may be applied to the substrate surface by any technique effective in functioning the buffer layer as described. Specific exemplary techniques include chemical vapor deposition, physical vapor deposition, and atomic layer deposition techniques.

[0040] After depositing one or a combination of yttrium oxide coatings, the deposited yttrium oxide coating or combination of coatings is treated by a fluorination process, such as a fluoroannealing process (the "fluoroannealing" process) that converts at least a portion of the total amount of yttrium oxide of the deposited coating to yttrium fluoride (YF3) or yttrium oxyfluoride (YOF). The fluorination process will cause at least the exposed surface portion of the yttrium oxide coating and the yttrium oxide disposed near it to be at least partially converted to a yttrium fluoride material, such as yttrium fluoride or yttrium oxyfluoride. Methods of fluorinating yttrium oxide and yttrium oxide-containing materials (e.g., aluminum yttrium oxide) and related articles are described, for example, in U.S. Patent Publication Nos. 2016 / 0273095 and 2018 / 0202047, each of which is incorporated herein by reference in its entirety.

[0041] The fluoroannealing process can be carried out at a temperature and for a time effective to convert at least a substantial portion of the yttrium oxide of the deposited yttrium oxide precursor coating to yttrium oxyfluoride (YOF) or yttrium fluoride (YF3), particularly in the surface portion of the deposited yttrium oxide precursor coating.

[0042] A useful and preferred fluoroanneal technique involves exposing the yttrium oxide surface to a molecular fluorine source vapor at a temperature effective to react the fluorine of the molecular fluorine source vapor with the yttrium oxide of the deposited yttrium oxide coating (also known as the "yttrium oxide layer") to form yttrium fluoride or yttrium oxyfluoride or combinations thereof on and beneath the surface of the deposited yttrium oxide precursor coating.

[0043] As used herein, "molecular fluorine source vapor" is a non-plasma (i.e., molecular) fluorine-containing chemical molecule in vapor (gas) form, which is not considered a plasma. A "plasma" is a non-solid vapor phase composition containing a high density of ion fragments derived from one or more plasma precursor compounds intentionally exposed to energy (e.g., from a radio frequency power source) for the purpose of decomposing the plasma precursor compounds into ions and using those ions for the treatment of a workpiece. In contrast to a plasma, a useful or preferred molecular fluorine source vapor may contain less than 1×10E-5 atomic percent ionized material, e.g., less than 1×10E-6 atomic percent ionic species.

[0044] The molecular fluorine source vapor may be supplied to the process chamber for forming the yttrium fluoride coating by any method or from any useful and effective source or location. In a useful or preferred method, the molecular fluorine source vapor may be generated in situ, which means within the process chamber used to form the yttrium fluoride coating on the surface during the process of forming the yttrium fluoride coating on the surface of the substrate. The molecular fluorine source vapor may be generated in situ from a non-gaseous fluorine source by heating the non-gaseous fluorine source to convert the molecules of the non-gaseous fluorine source into a gas, i.e., molecular vapor. The non-gaseous fluorine source may be a liquid or solid fluorine-containing substance, and the heating step produces a gaseous form of the molecules without causing significant decomposition or ionization of the molecules of the liquid or solid fluorine source. A useful or preferred gaseous form of the molecules may be at least 99.9999 atomic percent molecular, i.e., chemically unchanged molecules of the liquid or solid fluorine-containing substance. The gaseous form of the molecules may contain less than 1×10E-5 atomic percent ionized or decomposed material, e.g., less than 1×10E-6 atomic percent ionic species. In some embodiments, the fluorine vapor source may be introduced from a gas cylinder as a gaseous medium into the fluorination reactor.

[0045] The heating step for generating the molecular fluorine source vapor is different from the step of generating plasma, which is used in various semiconductor processing steps. Generally, the plasma generation step generally involves applying one or more forms of energy to a plasma source, which is generally a gaseous chemical substance, to ionize the plasma source and chemically decompose the molecules of the plasma source to produce ionic fragments of the molecules. The energy may be thermal energy (high temperature), electromagnetic irradiation, e.g., RF (irradiation) (generated by a radio frequency power source), or a combination thereof.

[0046] As a specific comparison, the heating process used to generate molecular fluorine source vapor is different from the process of generating a fluorine-containing plasma for use in a semiconductor processing tool for the process of plasma etching, plasma cleaning, or "seasoning" the process chamber of a semiconductor processing tool. An example of a plasma generation process different from the heating process being described currently is described in U.S. Patent No. 5,756,222, which describes a fluorine-containing plasma generated within a reaction chamber designed for a plasma etching or plasma cleaning process. The plasma is produced by exposing a fluorine precursor to RF power.

[0047] The fluoroannealing process can be performed at a high temperature within the process chamber by disposing a substrate having a surface with a deposited yttrium oxide coating deposited thereon within the process chamber in a removable, temporary non-operating mode; introducing molecular fluorine source vapor into the process chamber or heating a non-gaseous fluorine source to convert the molecules of the non-gaseous fluorine source into a gas, i.e., vapor, within the process chamber to generate molecular fluorine source vapor within the process chamber; and raising the temperature of the process chamber, the substrate, the deposited yttrium oxide coating, the molecular fluorine source vapor, or a combination thereof to cause a reaction between the fluorine of the molecular fluorine source vapor and the yttrium oxide of the deposited yttrium oxide coating to convert at least a portion of the yttrium oxide to fluorinated yttrium oxide. As used herein, the term "fluorinated yttrium oxide" refers to a yttrium oxide coating that has been treated by a fluorination process to convert at least a portion of the yttrium oxide to yttrium fluoride (YF3), yttrium oxyfluoride (YOF), or a combination of both. In some embodiments, the fluorine source vapor is heated independently of and / or to a different temperature than the yttrium oxide-coated substrate.

[0048] During the fluoroannealing process, the process chamber used to perform the process may contain a processing material including molecular fluorine source vapor, optionally a non-vapor fluorine source, and one or more substrates having a deposited yttrium oxide coating described herein deposited on the surface. The internal space and atmosphere of the chamber need not be evacuated and need not be at reduced pressure, and may contain a certain amount of air. For the fluoroannealing process, there is no need to exclude air or oxygen, nor is it necessary to introduce an inert gas (purging gas, such as N2) into the process chamber. The process chamber need not contain and may exclude any other additional gaseous or liquid processing materials other than air and molecular fluorine source vapor, for example, other gaseous materials such as inert gases or gaseous co-reactants that may sometimes be used in the gaseous atmospheres of other semiconductor processing steps.

[0049] The process chamber is not part of a semiconductor processing tool and need not, and preferably does not, contain any other workpiece being processed by other means, such as semiconductor devices, ultra-small electronic devices, or precursors thereof. The process chamber does not require and is not accompanied by the use of means for generating plasma, such as a radio frequency power source, or means for applying a potential (voltage) to a component or workpiece.

[0050] A useful process chamber preferably can include a temperature control device for controlling the temperature within the chamber; means for controlling the composition and purity of the environment inside the chamber, such as a pressure control device, a filter, etc.; components for temporarily accommodating and supporting one or more substrates, each having a combination of deposited yttrium oxide coatings, within the chamber for a period useful for converting at least a portion of the yttrium oxide of at least one exposed surface of the deposited yttrium oxide coating to fluorinated yttrium oxide; and components for controlling the composition of the atmosphere within the process chamber, including supplying a molecular fluorine source within the process chamber and controlling its amount and concentration.

[0051] According to a particular useful or preferred example of the fluoroannealing method, the molecular fluorine source vapor can be a gaseous fluorinated or perfluorinated organic compound, such as a fluorinated or perfluorinated alkane or alkene, any of which can be linear or branched. Examples include, in particular, CF4, C2F4, C3F6, C4F8, CHF3, C2H2F2, C2F6, HF, CH3F, each in molecular form, which means that it is substantially non-ionic and has not been subjected to treatment (by applying energy other than heat) for decomposition or plasma formation.

[0052] According to another useful or preferred exemplary method, the molecular fluorine source vapor can be a gaseous fluorinated polymer that has not been treated with energy to form a plasma. The gaseous fluorinated polymer can be derived from a non-gaseous (e.g., liquid or solid) fluorinated polymer, for example, by heating the non-gaseous fluorinated polymer in the presence of a deposited yttrium oxide coating that is desired to be converted to yttrium fluoride by the fluoroannealing process in a process chamber.

[0053] The fluorinated polymer can be any fluorinated polymer that is effective according to the described method for forming fluorinated yttrium oxide from a deposited yttrium oxide coating present on the surface of a substrate. Examples of useful fluorinated polymers include homopolymers and copolymers comprising polymerized fluoroolefin monomers and optionally non-fluorinated comonomers. The polymer can be fluorinated (i.e., partially fluorinated), perfluorinated, or can contain non-fluorine halogen atoms, such as chlorine. The molecular fluorine source can be liquid or solid at room temperature, but becomes vapor at the temperature of the process chamber used according to the described method.

[0054] Non-limiting examples of certain fluoropolymers include C1-C 10Polymerized perfluoroalkyl ethylene having a perfluoroalkyl group; polytetrafluoroethylene (PTFE); tetrafluoroethylene / perfluoro(alkyl vinyl ether) copolymer (PFA); tetrafluoroethylene / hexafluoropropylene copolymer (FEP); tetrafluoroethylene / perfluoro(alkyl vinyl ether) / hexafluoropropylene copolymer (EPA); polyhexafluoropropylene; ethylene / tetrafluoroethylene copolymer (ETFE); polychlorotrifluoroethylene; polyvinylidene fluoride (PVDF); polyvinyl fluoride (PVF); polychlorotrifluoroethylene (PCTFE); ethylene / chlorotrifluoroethylene copolymer (ECTFE); or a combination thereof.

[0055] The fluorannealing process described can be carried out at any temperature effective to react fluorine from the fluorine source vapor with yttrium oxide of the deposited yttrium oxide coating to convert at least a portion of the deposited yttrium oxide coating to yttrium oxyfluoride, yttrium fluoride, or a combination thereof. A relatively high temperature may be useful or preferred to convert yttrium oxide to a high concentration of yttrium fluoride (YF3) instead of yttrium oxyfluoride (YOF) by reacting the fluorine source vapor with yttrium oxide. Exemplary temperatures for the fluorannealing process may be at least 300 or 350 degrees Celsius or higher, for example in the range of 300 to 500 degrees Celsius, for example from 350 or 400 to 425 or 450 degrees Celsius, to produce a high concentration of YF3 in the surface portion of the deposited thin film.

[0056] The process chamber can be operated at any useful pressure, and exemplary pressures are approximately atmospheric pressure (760 Torr), for example 100 to 1500 Torr, for example from 250 or 500 to 1000 or 1250 Torr. The atmosphere in the process chamber for converting yttrium oxide to yttrium fluoride may include a portion that is air in combination with the molecular fluorine source vapor.

[0057] The amount of time used to form yttrium fluoride by the fluoroannealing process can be based on factors such as the temperature of the fluoroannealing process, the type and amount (concentration) of the molecular fluorine source vapor in the process chamber, the thickness and composition of the deposited yttrium oxide coating, and the desired depth of the yttrium oxide coating that is preferably converted to yttrium fluoride, yttrium oxyfluoride, or a combination thereof. Exemplary amounts of useful or preferred times can range from 1 to 48 hours, such as, for example, 2 to 24 hours, or 3 to 12 hours. The time useful for performing the fluoroannealing process can be the time to produce a yttrium fluoride or yttrium oxyfluoride portion (of the deposited yttrium oxide coating) having a useful or preferred thickness. During the fluoroannealing process, as the deposited yttrium oxide coating is continuously exposed to the molecular fluorine source vapor, the thickness will increase over time. After a certain amount of time, such as after 12, 18, or 24 hours, the thickness of the fluorinated portion of the deposited yttrium oxide coating may not increase substantially further.

[0058] The described fluorinated yttrium oxide coating, formed by converting at least a portion of the yttrium oxide of the deposited yttrium oxide coating to yttrium fluoride or yttrium oxyfluoride, will have a composition containing yttrium, fluorine, oxygen, and optionally a small amount of carbon (e.g., less than 4 or 5 atomic percent carbon). For example, the fluorinated yttrium oxide coating may contain yttrium fluoride (YF3), yttrium oxyfluoride (YOF) (also known as yttrium oxofluoride), and optionally yttrium oxide (Y2O3). These different yttrium-containing materials may vary in different portions in the thickness (depth) direction of the coating, based on the location of the thickness of the deposited material, i.e., in an amount (concentration) that varies with respect to the depth (thickness) of the fluorinated yttrium oxide coating (i.e., a non-uniform amount or concentration).

[0059] When the yttrium oxide fluoride coating is coated such that the yttrium oxide precursor coating contains a non-yttrium metal or a non-yttrium metal oxide, such as aluminum oxide, it can also contain the non-yttrium metal, the non-yttrium metal oxide, or both of them.

[0060] As used herein, the term "yttrium oxide fluoride coating" refers to a film or coating formed on a substrate by depositing a yttrium oxide (precursor) coating on the substrate and then converting at least a portion of the deposited yttrium oxide to yttrium fluoride or yttrium oxyfluoride. By these steps, not all of the yttrium oxide of the deposited yttrium oxide film is necessarily converted to yttrium fluoride or yttrium oxyfluoride. A portion of the thickness of the coating, including the exposed surface of the coating (i.e., the "surface portion"), will be converted to a large extent to yttrium fluoride, yttrium oxyfluoride, or a combination thereof. In a coating having a sufficient thickness, the middle or lower portion of the coating may be converted to yttrium fluoride or yttrium oxide fluoride (YOF) and may contain a higher concentration of oxygen compared to locations closer to the surface. Optionally, the lower portion of the coating may be converted to yttrium fluoride, converted to yttrium oxide fluoride, or remain in the form of yttrium oxide if the coating has a sufficient thickness.

[0061] Based on a method of depositing a fluorinated yttrium oxide coating and then fluorinating it, the coating may exhibit non-uniform, e.g., stepwise, concentrations of one or more of the atomic components that make up the coating, particularly fluorine and oxygen. The concentration of fluorine within the fluorinated yttrium oxide coating may decrease along the thickness direction of the coating such that the surface and outer portion ("upper portion" or "surface portion") of the coating contains a higher concentration of fluorine compared to the deeper portions. For example, in some embodiments, the coating can have an upper portion made substantially of yttrium fluoride and a lower portion that is fluorinated yttrium oxide or even non-fluorinated yttrium oxide.

[0062] Different portions of the deposited thin film can be identified and described by X-ray photoelectron spectroscopy, i.e., "XPS" technology, based on the varying composition at different thickness locations of the film. This quantitative spectroscopic technique enables compositional analysis of the deposited material's film or layer over the thickness (depth) of the deposited material, both at the surface and beneath the surface of the material. In XPS profiling analysis, the elemental composition of the deposited material can be specified at different locations along the thickness direction of the material.

[0063] The described protective coatings containing a combination of at least two different coatings can be fluorinated using one or more separate fluorination steps in any useful manner. Each of the different coatings in the combination can be fluorinated separately (individually in the absence of the other coatings) after deposition of the individual coatings, or alternatively, first a combination of two or more coatings can be deposited and then the surface of the exposed coating can be fluorinated by a single fluorination step.

[0064] More specifically, the described coating combinations can include two yttrium oxide coatings on a substrate that includes a high aspect ratio surface and a non-high aspect ratio surface. One coating, referred to as the "first" yttrium oxide coating, coats at least the high aspect ratio surface, and at least one coating, referred to as the "second" yttrium oxide coating, coats at least the non-high aspect ratio surface. The two coatings can be applied in any desired order and fluorinated in any desired order. Other coatings, such as buffer layers, can be deposited on the substrate at different locations with respect to the two yttrium oxide coatings.

[0065] As used herein, the terms "first" and "second" when referring to the "first yttrium oxide coating" and the "second yttrium oxide coating" are used to indicate that the coated substrate includes at least two different types of yttrium oxide coatings. The terms "first" and "second" do not require that either one or the other of the two different types of coatings be deposited on the substrate in any particular order. The "second" yttrium oxide coating can be deposited in a process that occurs either before or after the process of depositing the "first" yttrium oxide coating. Also, the "first" yttrium oxide coating can be deposited in a process that occurs either before or after the process of depositing the "second" yttrium oxide coating. The "second" yttrium oxide coating can be located either above (on top of) or below (closer to the substrate surface) the "first" yttrium oxide coating. Also, the "second" yttrium oxide coating can be located either above (on top of) or below the "first" yttrium oxide coating. See FIGS. 2B - 2G, including FIGS. 2C and 2E in particular, which show the "second" PVD coating deposited before and located below the "first" ALD coating.

[0066] As a specific example, the first coating may be applied by atomic layer deposition (ALD) to coat high aspect ratio surfaces and non-high aspect ratio surfaces, for example, this may be a sealing coating. Thereafter, a "targeted" method, such as physical vapor deposition, may be used to apply a partial coating to the substrate to coat the non-high aspect ratio surfaces. In some embodiments, the partial coating also coats at least a portion of the high aspect ratio surfaces. Optionally, one or two fluorination steps may be used to fluorinate the coating. The first fluorination step may be performed after the first deposited (e.g., sealing) coating is deposited, and the second fluorination step may be performed after the second deposited (e.g., partial) coating is deposited. Alternatively, a single fluorination step may be performed after both the first and second coatings are deposited.

[0067] As a different example, in the first step, a partial coating may be applied to the non-high aspect ratio surfaces by a "targeted" deposition method, such as physical vapor deposition (PVD). In a subsequent step, a sealing coating may be applied, for example, by atomic layer deposition. Optionally, one or two fluorination steps may be used to fluorinate the coating. The first fluorination step may be performed after the first (e.g., partial) coating is deposited, and the second fluorination step may be performed after the second (e.g., sealing) coating is deposited. Alternatively, a single fluorination step may be performed after both the first (e.g., partial) coating and the second (e.g., sealing) coating are deposited. As described, the partial coating is located on the surface of the substrate that does not include high aspect ratio features (e.g., the "main" surface), and the sealing coating is deposited on the surface of the substrate that includes the surfaces of the high aspect ratio features (e.g., the "secondary" surface).

[0068] Thinking differently, the described series of steps for manufacturing a substrate comprising a surface coated with one or more fluorinated yttrium oxide coatings, including high aspect ratio surfaces and non-high aspect ratio surfaces, involves depositing a yttrium oxide precursor coating on the substrate by atomic layer deposition to place the yttrium oxide precursor coating on the high aspect ratio surface, and optionally and preferably, placing the yttrium oxide precursor coating on other surfaces of the substrate including surfaces other than the surface that is part of the high aspect ratio feature; fluorinating the atomic deposited yttrium oxide precursor coating to form a fluorinated yttrium oxide coating on the surface of the high aspect ratio feature; depositing a partial coating of yttrium oxide on the surface of the substrate other than the surface of the high aspect ratio feature by a "targeting" method, such as physical vapor deposition; and fluorinating a second yttrium oxide coating to form a yttrium fluoride coating, and may include steps performed in any useful order. The two different yttrium oxide coatings may be deposited in any order, for example, by first depositing a partial coating of yttrium oxide and then depositing a yttrium oxide precursor coating on the surface of the high aspect ratio feature (e.g., as a sealing coating on the entire surface of the substrate); or by first depositing a yttrium oxide precursor coating on the surface of the high aspect ratio feature (e.g., as a sealing coating on the entire surface of the substrate); and then depositing a partial coating of the yttrium oxide coating on a surface other than the surface of the high aspect ratio feature. Fluorinating the yttrium oxide of the different coatings may be done separately for each individual coating after deposition, or may be done as a single fluorination step after the two steps of depositing the two different yttrium oxide coatings.

[0069] Referring now to FIG. 1, an example of a substrate for use in semiconductor processing equipment is illustrated. Substrate 10 is in the form of an opening plate or disk of a showerhead (or "electrode"), which is useful for introducing a flow of gaseous fluid from a fluid source into the internal space of the semiconductor processing equipment. The opening plate 10 is shown as being flat, but may assume a curved surface form. The opening plate 10 may be made of any useful material, such as ceramic, semiconductor material (e.g., silicon), or metal or metal alloy.

[0070] As shown, the opening plate 10 includes a front surface 12 that will face the interior of the process chamber during use. The rear surface 16 will face the source of the gaseous fluid. During use, the gaseous fluid will flow from the source through the apertures 14 of the opening plate 10 into the interior of the process chamber.

[0071] The opening plate 10 includes a substantially planar (flat or slightly curved) front surface 12, a rear surface 16, and a plurality of apertures 14. The front surface 12 includes a circular boundary (or common end) with the plurality of apertures 14, but is substantially flat or planar and does not include the surface of a high aspect ratio feature. Thus, the front surface 12 may be regarded as the main surface described herein, i.e., a non-high aspect ratio surface. Since the front surface 12 will come into extensive contact with process chemicals during use, it may be coated with the described protective fluorinated yttrium oxide coating by a deposition method adapted to coat the exposed non-high aspect ratio main surface of the substrate.

[0072] Each aperture 14 has an inner aperture surface 18. Each aperture has an aspect ratio defined by the thickness of the plate 10 per diameter of each aperture 14 (the aspect ratio of each aperture 14 is t:D. The aspect ratio may be at least 2:1, 5:1, 10:1, or 20:1, or more. Each aperture 14 is defined by the inner aperture surface 18, which is substantially cylindrical having a diameter "D" and a height (thickness) "t". The inner aperture surface 18 is part of the aperture 14, which can be a three-dimensional structure that can be part of a high aspect ratio feature of the substrate 10, and thus, the inner aperture surface 18 can be considered a sub-surface and a "high aspect ratio" surface of the substrate 10. Since the inner aperture surface 18 will also be in the environment of the process fluid during use, it can be coated with the described protective fluorinated yttrium oxide coating. However, the inner aperture surface 18 is more difficult to coat than the front surface 12 because it is not fully reachable by "line-of-sight" deposition methods, especially when the thickness t of the plate 10 is substantially greater than the diameter D of each aperture. To place the protective fluorinated yttrium oxide coating on the inner aperture surface 18, a coating method, such as atomic layer deposition, capable of depositing a highly conformal coating by a non-line-of-sight method on a substrate including high aspect ratio surface features (e.g., apertures 14) is preferred. Referring now to FIGS. 2A through 2G, exemplary structures and method steps of the present specification are illustrated. FIG. 2A shows a legend of yttrium oxide and fluorinated yttrium oxide materials for FIGS. 2B through 2G. Overall in these figures, the coating and fluorination thicknesses are not to scale. Typically, the PVD coating may be in the range of 50 to 100 times thicker than the ALD coating. The thickness of the fluorinated portion is also not to scale.

[0073] All of the illustrated exemplary coated substrates shown a PVD coating applied to only one side of the substrate. Optionally, after coating one surface, the substrate can be flipped over and a second coating applied to the second surface to apply the PVD coating to both surfaces.

[0074] In the illustrated example, it is shown that the PVD coating abruptly ends between the top surface and the side surface, which is a simplification. In reality, the PVD coating will exhibit a gradual transition from the full thickness on the exposed surface to a reduced thickness or no coating as the coating approaches the boundary with the high aspect ratio feature (e.g., the aperture 104). Optionally, depending on factors that may include coating conditions, the chemical composition of the material being coated, and the morphology and material of the substrate (e.g., a previous coating), a second coating deposited on a non-high aspect ratio surface (e.g., a PVD coating) may also cover at least a portion of the high aspect ratio feature.

[0075] The legends refer to "fluorinated ALD" and "fluorinated PVD". Depending on the fluorination conditions (mainly the fluorination temperature), the fluorinated ALD coating may contain YOF or YF3, and the fluorinated PVD coating will contain YOF. Consistent with this, a lower temperature fluorination process may produce PVD YOF and ALD YOF. A higher temperature fluorination process may produce PVD YOF and ALD YF3 on the outer surface.

[0076] Since the ALD layer can be made thin (e.g., about 100 nm), depending on the fluorination conditions (temperature and time), it is possible to produce a highly fluorinated ALD layer throughout the layer thickness, and fluorine can reach throughout the layer from the top surface to the bottom surface. However, the fluorine content may have a gradient. Possibly, most of the outer surface or outer region may be converted to YF3, and YOF may be present in gradually increasing amounts further away from the outer surface. ALD alumina as a buffer layer is a barrier to fluorine. The fluorine content will abruptly end in the ALD alumina buffer layer. PVD yttria is typically much thicker (more than 5 microns), and fluorine does not spread throughout the thickness of the PVD yttria layer.

[0077] In each of FIGS. 2B through 2G, an exemplary coated substrate includes a plurality of yttrium oxide coatings (at least one coating covering the high aspect ratio surface 106 and at least one coating covering one or both of the opposing non-high aspect ratio surfaces 108 and 110). At least a portion of the exposed (outer) surface of the coating combination is fluorinated. Optionally, both of at least two different coatings include fluorinated surfaces, but the coatings and methods described do not require that a portion of all yttrium oxide coatings or all surfaces of yttrium oxide coatings deposited as components of the described coating combinations include fluorinated surfaces. For example, a partially yttrium oxide coating covered by different yttrium oxide coatings (e.g., atomic layer deposition coatings) may be part of the combination but may not include surfaces exposed to the fluorination process (see FIG. 2B).

[0078] FIG. 2B shows an enlarged view of a substrate 100 having high aspect ratio features in the form of a plurality of apertures 104 (the substrate 100 may be the plate 10 of FIG. 1) (only one aperture is shown). The substrate 100 includes a front face 102 having a front surface 110, a rear surface 108, and a plurality of apertures 104 (only one is shown) that extend completely from the front surface 110 to the rear surface 108. The front surface 110 is substantially planar, does not include high aspect ratio features, and may be considered a major surface and a non-high aspect ratio surface as described herein.

[0079] Each aperture 104 is defined by a diameter D and a width "W", and the width "W" is equal to the thickness "t" of the substrate 100. Each aperture 104 is also defined by an aperture inner surface 106, which is considered a secondary surface and a high aspect ratio surface as described herein as the surface of a three-dimensional structure (aperture 104).

[0080] The coated substrate 100 includes an intermediate or "buffer" layer 105 on part or all of the substrate surface including the front surface 110, the back surface 108, and all the inner surfaces 106 of the apertures.

[0081] Referring to Figure 2B, in the first step of the exemplary method described, an alumina buffer layer 105 is directly deposited on the surface of the substrate 100 including the non-high aspect ratio front surface 110, the high aspect ratio inner surface 106 of the aperture, and the non-high aspect ratio back surface 108 by atomic layer deposition. In the second step, a yttrium oxide coating 120 is deposited on the substrate 100 on top of the buffer layer 105 by atomic layer deposition. The atomic layer deposited yttrium oxide coating 120 completely covers at least the inner surface 106 of the aperture 104. As shown, the atomic layer deposited yttrium oxide coating 120 covers the entire surface of the substrate 100 including the front surface 110 and the back surface 108. In this example, the atomic layer deposited yttrium oxide coating 120 is a sealing coating.

[0082] Still referring to Figure 2B, in a subsequent step, a partially yttrium oxide coating 130 is deposited on the substrate 100 on top of the yttrium oxide coating 120 previously deposited on the front surface 110. The partial coating 130 is located only on the front surface 110 and is not located on either the back surface 108 or the inner surface 106 of the aperture. The partial coating 130 may have a thickness greater than the thickness of the yttrium oxide coating 120. The partial coating 130 can be deposited using any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a targeted deposition technique.

[0083] Referring further to FIG. 2B, after depositing the yttrium oxide coating 120 by atomic layer deposition and then subjecting the substrate coated with two different types of yttrium oxide coatings (120, 130) to a subsequent process after depositing the yttrium oxide coating 130 by a different method, e.g., a templating method, to a fluorination process to cause fluorination of the outer surface of the coating combination. As shown by the fluorinated portion 122 of the atomic layer deposited yttrium oxide coating 120 and as shown by the fluorinated portion 132 of the physical vapor deposited coating 130, the exposed outer surfaces of the coatings 120 and 130 are treated by the fluorination process and at least a portion 122 and 132 of the total amount of yttrium oxide of each of the coatings 120 and 130 is chemically converted to yttrium fluoride.

[0084] However, it should be noted that the yttrium oxide coating 120 may not be fluorinated in all locations (regions) of the coating. The yttrium oxide coating 130 covers the yttrium oxide coating 120 at the surface 110. The portion of the yttrium oxide coating 120 that is between the surface 110 and the yttrium oxide coating 130 may not be fluorinated. However, the portion of the yttrium oxide coating 120 that covers the surface 106 of the high aspect ratio feature or other surfaces not covered by the sublayer 130 will be at least partially fluorinated.

[0085] Figure 2C shows an alternative combination of coatings produced by an alternative process for making the coated substrate described, using the same numbering as in Figure 2A. Figure 2C shows a substrate 100 that has been processed to have two described yttrium oxide coatings. In a first step, a partial yttrium oxide coating 130 is deposited on the substrate 100 at the front surface 110. The partial coating 130 is located only on the front surface 110 and not on either the back surface 108 or the inner surface 106 of the aperture. The partial coating 130 can be deposited using any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a targeted deposition technique. In a subsequent step, an aluminum oxide buffer layer 105 is deposited by atomic layer deposition to cover any exposed surfaces of the substrate 100, including the partial coating 130 and the inner surface 106 of the aperture.

[0086] Thereafter, a yttrium oxide coating 120 is deposited on the substrate 100 by atomic layer deposition. The yttrium oxide coating 120 covers at least each inner surface 106 of the aperture 104. As shown, the yttrium oxide coating 120 covers the entire surface of the substrate 100, including the front surface 110 (previously coated with the partial coating 130) and the back surface 108. In this example, the atomic layer deposition yttrium oxide coating 120 is a sealing coating.

[0087] Referring further to FIG. 2C, after depositing the yttrium oxide coating 130 by a method of disposing a coating on (directly on) the surface 110, and subsequent steps after depositing the buffer layer 105 and the yttrium oxide coating 120 by atomic layer deposition respectively, the substrate coated with two yttrium oxide coatings is processed by a fluorination process. As indicated by the fluorinated portion 122 of the coating 120, at least the outer portion 122 of the coating 120 has been processed by the fluorination process, and at least a portion of the total amount of yttrium oxide in the coating 120 has been chemically converted to yttrium fluoride. Note that the partial coating 130 covered by the buffer layer 105 and the atomic layer deposited yttrium oxide coating 120 may not contain any portion that is converted to a fluorinated portion.

[0088] FIG. 2D shows a further alternative coated substrate and the process of making the described coated substrate using the same numbering as FIGS. 2A and 2C. In a first step, the buffer layer 105 is deposited by atomic layer deposition. Next, a yttrium oxide coating 120 is deposited on the substrate 100 and the buffer layer 105 by atomic layer deposition. The yttrium oxide coating 120 covers at least each inner surface 106 of the apertures 104. As shown, the yttrium oxide coating 120 covers the entire surface of the substrate 100 including the front surface 110 and the rear surface 108, and in this example, the yttrium oxide coating is a sealing coating.

[0089] In the fluorination process, the yttrium oxide coating 120 is fluorinated to produce a fluorinated portion 122.

[0090] In a subsequent step, a partial yttrium oxide coating 130 is deposited on the substrate 100 over the yttrium oxide coating 120 previously deposited on the front surface 110. The partial coating 130 is located only on the front surface 110 and is not located on either the back surface 108 or the inner surface 106 of the opening. The partial coating 130 may have a thickness greater than the thickness of the yttrium oxide coating 120. The partial coating 130 can be deposited using any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a targeted deposition technique.

[0091] In a second fluorination step, the yttrium oxide coating 130 is fluorinated. As shown by portions 122 and 132, each of the coatings 120 and 130 has been treated by the fluorination step, and at least the outer portion of the total amount of yttrium oxide in each of the coatings 120 and 130 has been chemically converted to yttrium fluoride (122, 132).

[0092] FIG. 2E shows, using the same numbering as FIGS. 2B - 2D, an alternative coated substrate and the process for making the described coated substrate. In a first step, a partial yttrium oxide coating 130 is deposited on the substrate 100 at the front surface 110. The partial coating 130 is located only on the front surface 110 and is not located on either the back surface 108 or the inner surface 106 of the opening. The partial coating 130 can be deposited using any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a targeted deposition technique.

[0093] In the fluorination step, the yttrium oxide coating 130 is fluorinated to produce a fluorinated portion 132.

[0094] After depositing the yttrium oxide coating 130 by a method of disposing a coating on the surface 110, and subsequent to fluorinating the yttrium oxide coating 130, the buffer layer 105 is applied by atomic layer deposition in a subsequent process. Thereafter, by atomic layer deposition, on the buffer layer 105, a yttrium oxide coating 120 is deposited on the substrate 100. The yttrium oxide coating 120 covers at least each inner surface 106 of the apertures 104. As shown, the yttrium oxide coating 120 covers the entire surface of the substrate 100 including the front surface 110 (previously coated with the partial coating 130) and the back surface 108. In this example, the yttrium oxide coating is a sealing coating.

[0095] In a second fluorination step, the yttrium oxide coating 120 is fluorinated to form an outer fluorinated portion 122.

[0096] FIG. 2F shows, using the same figure numbering as FIGS. 2B - 2E, an alternative coated substrate and the process of making the described coated substrate. In a first step, a composite layer 140 of yttria and aluminum oxide is deposited on the substrate 100 at the front surface 110, the back surface 108, and the inner surface 106 by atomic layer deposition techniques. In a subsequent step, a partial coating 130 is deposited on the front surface 110 by any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a directed deposition technique. In a fluorination step, the exposed surfaces of the partial yttrium oxide coating 130 and the composite coating 140 are fluorinated to produce fluorinated portions 132 and 142.

[0097] Figure 2G shows the process of fabricating an alternative coated substrate and the described coated substrate using the same numbering as Figures 2B - 2F. In the first step, a composite layer 140 of yttrium oxide and aluminum oxide is deposited on the front surface 110, rear surface 108, and inner surface 106 of the substrate 100 by atomic layer deposition technology. In the first fluorination step, the composite coating 140 is fluorinated to produce a fluorinated portion 142. In subsequent steps, a partial coating 130 is deposited on the front surface 110 by any useful deposition method, such as physical vapor deposition, sputtering, plasma chemical vapor deposition, etc., which may be a targeted deposition technique. In the second fluorination step, the exposed surface of the partial yttrium oxide coating 130 is fluorinated to produce a fluorinated portion 132.

[0098] In a first aspect, the coated substrate includes a substrate having a high aspect ratio surface that is a feature with an aspect ratio of at least 2:1 and a non - high aspect ratio surface; and at least two coatings on the substrate, the coatings including a first yttrium oxide coating covering the high aspect ratio surface and a second yttrium oxide coating covering the non - high aspect ratio surface, and the outermost portion of the coatings includes fluorinated yttrium oxide on both the high aspect ratio surface and the non - high aspect ratio surface.

[0099] A second aspect includes the substrate of aspect 1, where the first yttrium oxide coating covers the high aspect ratio surface and at least a portion of the non - high aspect ratio surface, and the second yttrium oxide coating covers the non - high aspect ratio surface and at least a portion of the high aspect ratio surface.

[0100] A third aspect includes the substrate of the first or second aspect, where the first yttrium oxide coating is an atomic layer deposition coating.

[0101] The fourth aspect includes a substrate according to any one of the first to third aspects, wherein the second yttrium oxide coating is a physical vapor deposition coating.

[0102] The fifth aspect includes a substrate according to any one of the first to fourth aspects, wherein an outer portion of the first yttrium oxide coating includes yttrium fluoride, oxyfluoride yttrium, or a composite including aluminum oxide and yttrium fluoride or oxyfluoride yttrium.

[0103] The sixth aspect includes a substrate according to any one of the first to fifth aspects, wherein the first yttrium oxide coating has a thickness in the range of 50 to 500 nanometers.

[0104] The seventh aspect includes a substrate according to any one of the first to sixth aspects, wherein an outer portion of the second yttrium oxide coating includes oxyfluoride yttrium.

[0105] The eighth aspect includes a substrate according to the seventh aspect, wherein the second yttrium oxide coating has a thickness of at least 1 micron.

[0106] The ninth aspect includes a substrate according to any one of the first to eighth aspects, further including a yttrium-free buffer layer between the substrate surface and the first yttrium oxide coating, the second yttrium oxide coating, or both.

[0107] The tenth aspect includes a substrate according to the ninth aspect, wherein the buffer layer includes an atomic layer deposition layer including aluminum oxide.

[0108] The eleventh aspect includes a substrate according to the ninth or tenth aspect, further including a buffer layer covering a high aspect ratio surface and a non-high aspect ratio surface, a first coating covering the buffer layer on the high aspect ratio surface and the non-high aspect ratio surface, and a second coating covering the first coating on the non-high aspect ratio surface.

[0109] Aspect 12 includes a substrate of any of Aspects 1 to 11, including a second yttrium oxide coating deposited on a non-high aspect ratio surface and a first yttrium oxide coating deposited on a high aspect ratio surface and covering the second yttrium oxide coating.

[0110] Aspect 13 includes a substrate of Aspect 12, including a buffer layer deposited on the second yttrium oxide coating.

[0111] Aspect 14 includes a substrate of any of Aspects 1 to 13, where the substrate includes two opposing surfaces each having a length and a width dimension, a thickness between the two opposing surfaces, and an aperture extending between the two opposing surfaces. The aperture includes a high aspect ratio aperture surface extending along the thickness direction and an aperture diameter, and the ratio of the thickness to the aperture diameter (thickness:diameter) exceeds 5:1.

[0112] Aspect 15 includes a substrate of any of Aspects 1 to 14, where the feature has an aspect ratio of at least 10:1.

[0113] Aspect 16 includes a substrate of any of Aspects 1 to 15, which is a process chamber component of a semiconductor processing device.

[0114] Aspect 17 includes a substrate of Aspect 16, selected from a showerhead or a part thereof, and an electrode or a part thereof.

[0115] In an 18th aspect, a method of coating a substrate including a high aspect ratio surface and a non-high aspect ratio surface includes depositing an atomic layer deposition yttrium oxide coating on the high aspect ratio surface, which is a feature having an aspect ratio of at least 2 to 1; depositing a non-atomic layer deposition yttrium oxide coating on the non-high aspect ratio surface either before or after depositing the atomic layer deposition yttrium oxide coating; and fluorinating an exposed surface of the coating on one or both of the high aspect ratio surface and the non-high aspect ratio surface.

[0116] A 19th aspect includes the method of the 18th aspect, wherein the atomic layer deposition coating includes yttrium oxide or yttrium aluminum oxide, and the method includes fluorinating an outer portion of the atomic layer deposition coating to produce yttrium fluoride, yttrium oxyfluoride, a combination of yttrium fluoride and aluminum oxide, or a combination of yttrium oxyfluoride and aluminum oxide.

[0117] A 20th aspect includes the method of the 18th or 19th aspect, wherein the non-atomic layer deposition yttrium oxide coating is deposited by physical vapor deposition.

[0118] A 21st aspect includes the method of any one of the 18th to 20th aspects, wherein the substrate includes two opposing surfaces each having a length and a width dimension, a thickness between the two opposing surfaces, and an aperture extending between the two opposing surfaces, the aperture includes a high aspect ratio aperture surface extending along the thickness direction and an aperture diameter, the atomic layer deposition yttrium oxide coating covers the high aspect ratio aperture surface, and the non-atomic layer deposition yttrium oxide coating covers at least a portion of the opposing surfaces.

[0119] A 22nd aspect includes the method of any one of the 18th to 21st aspects, wherein the atomic layer deposition yttrium oxide coating has a thickness in the range of 50 to 500 nanometers.

Claims

1. A substrate including a high aspect ratio surface, which is a feature having an aspect ratio of at least 2:1, and a non-high aspect ratio surface; At least two coatings on the substrate comprising coatings that A first yttrium oxide coating covering the high aspect ratio surface; and A second yttrium oxide coating covering the non-high aspect ratio surface A coated substrate, wherein In both the high aspect ratio surface and the non-high aspect ratio surface, the outermost portion of the coating contains fluorinated yttrium oxide, The yttrium-containing material is present in different portions in the thickness direction of the coating and is present in a non-uniform amount or concentration that varies based on the thickness position of the deposited material.

2. The substrate according to claim 1, wherein the first yttrium oxide coating contains yttrium oxide or yttrium aluminum oxide.

3. The substrate according to claim 1, wherein the second yttrium oxide coating has a thickness of at least 1 micron.

4. The substrate according to any one of claims 1 to 3, wherein the outer portion of the first yttrium oxide coating contains a composite including yttrium fluoride, oxyfluoride yttrium, or a composite of aluminum oxide and yttrium fluoride or oxyfluoride yttrium.

5. The substrate according to any one of claims 1 to 3, wherein the outer portion of the second yttrium oxide coating contains oxyfluoride yttrium.

6. The substrate according to any one of claims 1 to 3, including a yttrium-free buffer layer between the substrate surface and the first yttrium oxide coating, the second yttrium oxide coating, or both.

7. A method of coating a substrate including a high aspect ratio surface and a non-high aspect ratio surface, comprising: Depositing an atomic layer deposition yttrium oxide coating on a high aspect ratio surface, which is a feature having an aspect ratio of at least 2:1; and Depositing a non-atomic layer deposition yttrium oxide coating on the non-high aspect ratio surface before or after depositing the atomic layer deposition yttrium oxide coating. Fluorinating the exposed surfaces of one or both of a high aspect ratio surface and a non-high aspect ratio surface by exposing the surface of yttrium oxide to a molecular fluorine source vapor A method comprising the above. **Claim 8** The method according to claim 7, wherein the atomic layer deposition coating comprises yttrium oxide or yttrium aluminum oxide, and the method comprises fluorinating an outer portion of the atomic layer deposition coating to produce yttrium fluoride, yttrium oxyfluoride, a combination of yttrium fluoride and aluminum oxide, or a combination of yttrium oxyfluoride and aluminum oxide. **Claim 9** The method according to claim 7 or 8, comprising depositing a non-atomic layer deposition yttrium oxide coating by physical vapor deposition. **Claim 10** The substrate is Two opposing surfaces each having a length and a width dimension,[[]] A thickness between the two opposing surfaces,[[]] An aperture extending between the two opposing surfaces Including The aperture includes a high aspect ratio aperture surface extending along the thickness direction and an aperture diameter,[[]] The atomic layer deposition yttrium oxide coating covers the high aspect ratio aperture surface,[[]] The method according to claim 7 or 8, wherein the non-atomic layer deposition yttrium oxide coating covers at least a portion of the opposing surfaces.

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