Protective metal oxy-fluoride coating

Abstract

To provide a metal oxy-fluoride (MOF) protective coating that is resistant to reaction with fluorine chemistries.SOLUTION: The protective coating is a thin film that comprises a metal oxy-fluoride. The metal oxy-fluoride has an empirical formula of MxOyFz, where M is a metal, y has a value of 0.1 to 1.9 times a value of x and z has a value of 0.1 to 3.9 times the value of x. The protective coating has a thickness of 1 to 30 microns and a porosity of less than 0.1%.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to protective metal oxyfluoride coatings that may be used on semiconductor process chamber components and methods for making protective metal oxyfluoride coatings that may be used on semiconductor process chamber components.

[0002] Semiconductor wafer manufacturing processes take place in chambers where chamber components are exposed to high temperatures, high energy plasmas, corrosive gas mixtures, high stresses, and combinations thereof. Chamber components can be shielded from these extreme conditions by protective coatings. Metal oxides are often used to coat chamber components due to their resistance to erosion from plasma etching chemistries. Metal oxide coatings convert to metal fluorides upon exposure to fluorine-based chemistries during wafer processing. The conversion of metal oxides to metal fluorides is typically accompanied by a volume expansion, increasing stress on the coating. For example, the conversion of 1 mole of Y2O3 (yttria) to 2 moles of YF3 (yttrium fluoride) is accompanied by a theoretical volume expansion of about 60%. The volume expansion and added stress caused by the conversion of metal oxides to metal fluorides can cause blisters and / or particles in the chamber components, resulting in defects in the processed wafers. Overview

[0003] The thin film is explained below. x O y F z where M represents a metal element; y has a value between 0.1 and 1.9 times the value of x, and z has a value between 0.1 and 3.9 times the value of x. The MOF thin film has a thickness between 1 and 30 microns and a porosity of less than 0.1%. Examples of MOF thin films include protective coatings on surfaces of chamber components for semiconductor processing equipment.

[0004] Several methods are also described below. One method is x O y_source F z_source The method includes providing a MOF source material having an empirical formula of: y_source has a value between 0.1 and 1.9 times the value of x, and z_source has a value between 0.1 and 3.9 times the value of x. The MOF source material is deposited on the article by sputter deposition or evaporation to form a MOF coating on the article. For example, the article can include a semiconductor process chamber component. Similar to the MOF source material, the MOF coating on the article can include a MOF coating of M x O y_coating F z_coating The MOF coating has an empirical formula of: y_coating has a value between 0.1 and 1.9 times the value of x, and z_coating has a value between 0.1 and 3.9 times the value of x. Features of the MOF coating include a thickness between 1 and 30 microns and a porosity of less than 0.1%.

[0005] The second method includes providing a source material and depositing the source material on the article by sputter deposition or vapor deposition. The article can include one or more semiconductor processing chamber components. In one example of the second method, the source material is a metal. Oxygen and fluorine ions or radicals are introduced to the sputtered or evaporated metal during deposition to form a MOF coating on the article. In another example of this second method, the source material is a metal oxide (MO) and fluorine ions or radicals are introduced to the sputtered or evaporated metal oxide during deposition to form a MOF coating on the article. In a third example of this second method, the source material is a metal fluoride (MF) and oxygen ions or radicals are introduced to the sputtered or evaporated MF during deposition to form a MOF coating on the article. The MOF coating can be a metal oxide (MO) and oxygen ions or radicals are introduced to the sputtered or evaporated MF during deposition to form a MOF coating on the article. x O y_coating F z_coating The MOF coating has an empirical formula of: y_coating has a value between 0.1 and 1.9 times the value of x, and z_coating has a value between 0.1 and 3.9 times the value of x. The MOF coating has a thickness between 1 and 30 microns and a porosity of less than 0.1%. [Brief description of the drawings]

[0006] Embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, in the accompanying drawings in which like reference numerals refer to like elements. It should be noted that different references to "a" or "an" embodiment in the present disclosure are not necessarily limited to the same embodiment, but such references mean at least one. [Figure 1] 1 illustrates an exemplary architecture of a semiconductor manufacturing system, in accordance with one embodiment of the present invention. [Diagram 2] 1 illustrates a cross-sectional view of an exemplary article having a thin protective coating according to various embodiments. [Figure 3A] ~ [Figure 3B] 1 illustrates an exemplary deposition technique, according to various embodiments of the present invention. [Figure 4] 1 illustrates an exemplary method of forming a metal oxyfluoride coating on an article, according to one embodiment of the present invention. [Figure 5A] ~ [Figure 5C] 1 illustrates an exemplary method of forming a metal oxyfluoride coating on an article according to various embodiments of the present invention. Detailed Description of the Configuration and Examples

[0007] As mentioned above, metal oxide protective layers are used on articles to protect them from exposure to plasma. Metal oxide coatings convert to metal fluorides when exposed to fluorine-based chemistries, and this conversion is accompanied by deposition expansion and particle defects on the processed wafer. Fluorine-based chemistries are often used to plasma etch substrates.

[0008] Described herein are embodiments of metal oxyfluoride (MOF) protective coatings that are resistant to reactions with fluorine chemistry. The MOF coatings described in the embodiments herein significantly reduce fluorination of the coating compared to MO coatings. Additionally, the MOF coatings can have a thermal expansion coefficient that much more closely matches that of the chamber components compared to MF coatings. These features can improve the corrosion resistance of the coating for articles in semiconductor manufacturing environments and reduce particle defects resulting from the protective coating. Thin film MOF compositions having these features are described below along with several methods for forming the MOF coatings.

[0009] An exemplary embodiment of the thin film has the empirical formula M x O y F z where M is a metal generally having a positive valence configuration, O is oxygen, and F is fluorine. The subscripts represent the number of each atom relative to the other. For example, the value of y is 0.1 to 1.9 times the value of x, and the value of z is 0.1 to 3.9 times the value of x. In either case, the values ​​of all the subscripts in combination with the valences of each atom are balanced such that the thin film is electronically neutral. Additionally, thin film embodiments have a thickness of 1 to 30 microns and a porosity of less than 0.1%.

[0010] Several methods are available for producing thin film coatings with the above-mentioned advantages. For example, one method involves providing a MOF source material having the same empirical formula as the target coating. The source material is then deposited on the article by sputter deposition or vapor deposition. In another method, the source material is a metal. The metal is sputtered or vapor deposited on the article in the presence of oxygen and fluorine ions or radicals (e.g., formed by a plasma or emitted from an ion gun). In either case, as the ions or radicals are deposited on the article, they collide with the sputtered source material and combine with the metal, forming a MOF coating on the article.

[0011] One method involves providing an MOF source material. The source material is sputtered or evaporated onto the article, and the source material is bombarded by oxygen ions or radicals as it deposits on the article. As a result, an MOF coating is formed on the article. Alternatively, another method involves providing an MO source material and sputtering or evaporating the source material onto the article. The source material is bombarded by fluorine ions or radicals as it deposits on the article, forming an MOF coating.

[0012] An advantage of depositing coatings by sputtering or evaporation is the ability to achieve porosity of less than 0.1%. Other deposition methods which achieve this advantage are considered equivalents of sputtering or evaporation.

[0013] The term "plasma-resistant material" refers to a material that is resistant to erosion and corrosion due to exposure to plasma treatment conditions. Plasma treatment conditions include plasmas generated from halogen-containing gases (e.g., C2F6, SF6, SiCl4, HBR, NF3, CF4, CHF3, CH2F3, F, NF3, Cl2, CCl4, BCl3, and SiF4, among others) and other gases (e.g., O2, or N2O). The resistance of a material to plasma is measured by its "etch rate" (ER), which may have units of angstroms per minute (Å / min), throughout the operation of the coated component and the time of exposure to the plasma. Plasma resistance can also be measured by its erosion rate, which has units of nanometers per radio frequency hour (nm / RFHr), where 1 RFHr represents 1 hour of treatment under the plasma treatment conditions. Measurements can be taken after different treatment times. For example, measurements can be taken before treatment, after 50 hours of treatment, after 150 hours of treatment, after 200 hours of treatment, etc. Plasma resistant coating materials typically have an erosion rate of less than about 100 nm / RFHr. A single plasma resistant material can have multiple different plasma resistance or erosion rate values. For example, a plasma resistant material can have a first plasma resistance or erosion rate associated with a first type of plasma and a second plasma resistance or erosion rate associated with a second type of plasma.

[0014] When the terms "about" and "approximately" are used herein, they mean that the nominal values ​​presented are accurate within ±10%. Some embodiments are described herein with reference to chamber components and other articles installed in a plasma etching apparatus for semiconductor manufacturing. It should be understood that such plasma etching apparatus can also be used to manufacture microelectromechanical systems (MEMS) devices. Additionally, the articles described herein may be other structures exposed to plasma. The articles described herein may be chamber components for a processing chamber, such as a semiconductor processing chamber. For example, the article may be a chamber component for a plasma etching apparatus, a plasma cleaning apparatus, a plasma propulsion system, or other processing chamber. The processing chamber may be used in a process in which a corrosive plasma environment having plasma processing conditions is provided. For example, the processing chamber may be a chamber for a plasma etching apparatus or a plasma etching reactor, a plasma cleaning apparatus, or the like. Examples of chamber components include a substrate support assembly, an electrostatic chuck (ESC), a ring (e.g., a process kit ring or a single ring), chamber walls, a base, a gas distribution plate, a showerhead, a nozzle, a lid, a liner, a liner kit, a shield, a plasma screen, a flow equalizer, a cooling base, a chamber viewport, a chamber lid, etc.

[0015] Additionally, embodiments are described herein with reference to ceramic articles that reduce particulate contamination when used in process chambers for plasma-rich processes. It is believed that the ceramic articles described herein can also reduce particulate contamination when used in process chambers for other processes (e.g., non-plasma etching equipment, non-plasma cleaning equipment, chemical vapor deposition (CVD) chambers, physical vapor deposition (PVD) chambers, plasma-enhanced chemical vapor deposition (PECVD) chambers, plasma-enhanced physical vapor deposition (PEPVD) chambers, plasma-enhanced atomic layer deposition (PEALD) chambers, etc.).

[0016] FIG. 1 is a cross-sectional view of a semiconductor processing chamber 100 having one or more chamber components coated with a MOF thin film protective layer according to an embodiment of the present invention. The processing chamber 100 can be used in processes in which a fluorine-based corrosive plasma environment is provided. For example, the processing chamber 100 can be a chamber for a plasma etcher or plasma etch reactor, plasma cleaner, etc. that uses fluorine-based chemistry for etching and / or cleaning. Examples of chamber components that can include a MOF thin film protective layer include a substrate support assembly 148, an electrostatic chuck (ESC), a ring (e.g., a process kit ring or a single ring), chamber walls, a base, a gas distribution plate, a showerhead, a liner, a liner kit, a shield, a plasma screen, a flow equalizer, a cooling base, a chamber viewport, a chamber lid, a faceplate, a selective modulation device (SMD), etc. The MOF thin film protective layer, which is described in more detail below, can include yttrium oxyfluoride or other metal oxyfluorides.

[0017] In one embodiment, the processing chamber 100 includes a chamber body 102 and a showerhead 130 that enclose an interior volume 106. Alternatively, in some embodiments, the showerhead 130 can be replaced with a lid and a nozzle. The chamber body 102 can be fabricated from aluminum, stainless steel, or other suitable materials. The chamber body 102 generally includes a sidewall 108 and a bottom 110. Any of the showerhead 130 (or the lid and / or nozzle), the sidewall 108, and / or the bottom 110 can include a MOF thin film protective layer.

[0018] The outer liner 116 may be disposed adjacent the sidewall 108 and may protect the chamber body 102. The outer liner 116 may be fabricated and / or coated with a MOF thin film protective layer. In one embodiment, the outer liner 116 is fabricated from aluminum oxide.

[0019] An exhaust port 126 may be defined in the chamber body 102 and couple the interior volume 106 to a pumping system 128. The pumping system 128 may include one or more pumps and a throttle valve used to evacuate and regulate the pressure of the interior volume 106 of the processing chamber 100.

[0020] The showerhead 130 can be supported on the sidewall 108 and / or top of the chamber body 102. The showerhead 130 (or lid) can be opened to allow access to the interior volume 106 of the processing chamber 100 and can provide a seal for the processing chamber 100 when closed. A gas panel 158 can be coupled to the process chamber 100 and can provide process and / or cleaning gases to the interior volume 106 through the showerhead 130 or the lid and nozzles. The showerhead 130 is used in processing chambers used for dielectric etching. The showerhead 130 can include a gas distribution plate (GDP) having a plurality of gas distribution holes 132 therethrough. The showerhead 130 can include a GDP coupled to a showerhead base that is aluminum based or anodized aluminum based. The GDP can be fabricated from Si or SiC, or can be made of ceramic (e.g., Y2O3, Al2O3, Y3Al5O 12 (YAG), etc. As shown, the showerhead 130 includes a MOF coating 152 on a surface of the showerhead 130.

[0021] In processing chambers used for conductor etching (etching conductive materials), a lid can be used rather than a showerhead. The lid can include a central nozzle that fits into a central hole in the lid. The lid can be a ceramic such as Al2O3, Y2O3, YAG, or a ceramic compound including Y4Al2O9 and a solid solution of Y2O3-ZrO2. The nozzle can also be a ceramic such as Y2O3, YAG, or a ceramic compound including Y4Al2O9 and a solid solution of Y2O3-ZrO2. The lid, showerhead 130, and / or nozzle can be coated with a MOF thin film protective layer.

[0022] Examples of fluorine-based process gases that can be used to process substrates in the process chamber 100 include halogen-containing gases (e.g., C2F6, SF6, NF3, CF4, CHF3, CH2F3, F, NF3, and SiF4, among others). Examples of carrier gases that can be used include N2, He, Ar, and other gases that are inert (e.g., non-reactive) to the process gas.

[0023] In some embodiments, the processing chamber 100 can include a faceplate and / or a selective modulation device (SMD) that can be disposed above the showerhead. The faceplate and SMD are components used to provide a remote plasma to the processing chamber 100. The faceplate and SMD can be fabricated from aluminum (e.g., aluminum 6061) or other metals. In some examples, the faceplate and SMD have a plasma spray protective coating (e.g., a coating of Y2O3 for erosion protection). Additionally or alternatively, the faceplate and SMD can have a MOF thin film coating for erosion protection. These components can be used, for example, when the processing chamber is a remote plasma chamber (e.g., a selective removal product (SRP) chamber). In operation, a low intensity plasma exists between the faceplate and the SMD, through which radicals pass for selective etching. The SMD adjusts the selectivity of the plasma.

[0024] The substrate support assembly 148 is disposed below the showerhead 130 or lid within the interior volume 106 of the processing chamber 100. The substrate support assembly 148 includes a ceramic electrostatic chuck that holds the substrate 144 during processing and a cooling base coupled to the electrostatic chuck. An inner liner (not shown) may be coated on the periphery of the substrate support assembly 148. The inner liner may be a halogen-containing gas resistant material (e.g., as discussed with respect to the outer liner 116). In one embodiment, the inner liner may be fabricated from the same material as the outer liner 116. Additionally, the inner liner may be coated with a MOF thin film protective layer.

[0025] FIG. 2 shows a cross-sectional side view of an article (e.g., a chamber component) covered with a MOF thin film protective layer that is plasma resistant. At least a portion of the base or body 205 of the article 200 is coated with the MOF thin film protective layer 208. The article 200 may be a chamber component (e.g., a substrate support assembly, an electrostatic chuck (ESC), a ring (e.g., a process kit ring or a single ring), a chamber wall, a base, a gas distribution plate or showerhead, a liner, a liner kit, a shield, a plasma screen, a flow equalizer, a cooling base, a chamber viewport, a chamber lid, a faceplate, an SMD, etc.). The body 205 of the article 200 may be a metal, a ceramic, a metal-ceramic composite, a polymer, or a polymer-ceramic composite. In one embodiment, the body 205 of the article 200 is an aluminum alloy (e.g., 6061 aluminum) or stainless steel. In other embodiments, the body 205 of the article 200 is a ceramic material (e.g., Al2O3, Y2O3, AlN, SiO2, etc.). In other embodiments, the body 205 of the article 200 is a polymer-based material (eg, Kapton®, Teflon®, etc.).

[0026] Various chamber components are constructed of different materials. For example, the electrostatic chuck can be constructed of ceramic materials (e.g., Al2O3 (alumina), AlN (aluminum nitride), TiO (titanium oxide), TiN (titanium nitride) or SiC (silicon carbide) bonded to an anodized aluminum base. Al2O3, AlN and anodized aluminum have poor plasma erosion resistance. When exposed to a plasma environment with fluorine chemistry, the electrostatic puck of the electrostatic chuck can cause wafer chuck degradation, increased He leak rate, particle generation on the front and backside of the wafer, and metal contamination on the wafer after approximately 50 RFHrs of processing. The RFHrs is one processing hour.

[0027] Lids for plasma etching equipment used in conductor etching processes may be sintered ceramics (e.g., Al2O3) because Al2O3 has high bending strength and high thermal conductivity. Al2O3 exposed to fluorine chemistry forms AlF particles and aluminum metal contamination on the wafer.

[0028] Showerheads for etchers used to perform dielectric etch processes are typically formed of anodized aluminum bonded to a SiC faceplate. When such showerheads are exposed to plasma chemistries that contain fluorine, AlF can form due to plasma interaction with the anodized aluminum base. Additionally, high erosion rates of the anodized aluminum base can result in arcing, ultimately reducing the mean time to clean the showerhead.

[0029] Some chamber lids and other chamber components have thick protective layers on the plasma-facing surfaces to minimize particle generation and metal contamination and to extend the life of the lid. Plasma spraying and other thermal spraying techniques can be used to form the thick protective layers. Most thick coating techniques have long lead times. Furthermore, most thick coating techniques involve special surface preparation to prepare the article being coated (e.g., the lid) to receive the coating. Such long lead times and coating preparation steps can increase costs, reduce productivity, and inhibit refurbishment. Furthermore, most thick coatings have inherent cracks and pores that reduce defect performance on the wafer.

[0030] One drawback of many thick oxide coatings (e.g., plasma sprayed Y2O3) is that these coatings react with fluorine-based chemistries. For example, Y2O3 (yttrium oxide) plasma sprayed protective coatings can be used to protect chamber components from erosion caused by fluorine-based chemistries. Fluorine reacts with yttrium oxide to form yttrium fluoride on the surface of the plasma sprayed protective coating. That is, the plasma sprayed protective coating will absorb some percentage of fluorine. Absorption of fluorine by the plasma sprayed protective coating reduces the amount of fluorine available for the etching reaction. This can reduce the etch rate of the etching process. Fluorine can later be sputtered from the protective coating, which can increase the amount of fluorine available for future etching processes. Thus, it can reduce the stability of the etch rate of etching processes using fluorine chemistries.

[0031] Furthermore, fluorination of oxide coatings (e.g., conversion of yttria to yttrium fluoride) is accompanied by a volume expansion that can cause stresses on the surface of the coating and can also cause blisters on the surface. The stresses and / or blisters can cause particles to slough off the coating, resulting in particle contamination on the processed wafer.

[0032] The examples provided above represent a few of the chamber components whose performance can be improved through the use of the MOF thin film protective layers described in the embodiments herein.

[0033] 2, the body 205 of the article 200 can include one or more surface features (e.g., mesas 206). In the case of an electrostatic chuck, the surface features can include mesas, sealing bands, gas channels, helium holes, etc. In the case of a showerhead, the surface features can include bond lines, hundreds or thousands of holes for gas distribution, divots or bumps around gas distribution holes, etc. Other chamber components can have other surface features.

[0034] The MOF thin film protective layer 208 formed on the body 205 can conform to the surface features of the body 205. As shown, the MOF thin film protective layer 208 maintains the relative shape of the top surface of the body 205 (e.g., transfers the shape of a mesa). Additionally, the MOF thin film protective layer 208 can be thin enough so as not to block the holes of the showerhead or the He holes of the electrostatic chuck. In one embodiment, the MOF thin film protective layer 208 has a thickness of less than about 200 microns. In a further embodiment, the MOF thin film protective layer 208 has a thickness of less than 50 microns. In one embodiment, the MOF thin film protective layer 208 has a thickness of 1-30 microns. In one embodiment, the MOF thin film protective layer 208 has a thickness of 1-15 microns.

[0035] The MOF thin film protective layer 208 is a deposited ceramic layer that can be formed on the body 205 of the article 200 using an ion-assisted deposition (IAD) process or a physical vapor deposition (PVD) process. For example, the MOF thin film protective layer 208 can be deposited by sputter deposition or vapor deposition. Additionally, ions or radicals can be injected during sputtering or vapor deposition by an ion gun or plasma. The MOF thin film protective layer 208 deposited by IAD or PVD can have a relatively low film stress (e.g., compared to the film stress caused by plasma spraying). Additionally, the MOF thin film protective layer 208 deposited by IAD or PVD can have a porosity of less than 1%, and in some embodiments, less than about 0.1%. The MOF thin film protective layer 208 deposited by IAD or PVD is a dense structure, which can have performance advantages for use in chamber components. Additionally, the MOF thin film protective layer 208 can be crack-free during deposition and after continued use.

[0036] The MOF thin film protective layer 208 deposited by IAD or PVD can be deposited without first roughening the top surface of the body 205 or performing other time-consuming surface preparation steps. The ability to apply the MOF thin film protective layer 208 without first roughening the body 205 can be beneficial in some applications (e.g., electrostatic chucks) because roughening the body reduces the breakdown voltage of the body 205. Additionally, the MOF thin film protective layer 208 is very smooth, reducing both particle defects and metal contamination of the processed wafer.

[0037] The MOF thin film protective layer 208 is resistant to reactions with fluorine-based chemistries. Therefore, the fluorine concentration in the fluorine-based plasma can be maintained nearly constant during the etch and clean process. As a result, the etch rate also remains stable during the etch and clean process.

[0038] The MOF thin film protective layer 208 includes one or more metals, oxygen, and fluorine. Generally, the metals are those for which there is a volume increase of the metal fluoride compared to the corresponding MOF. That is, if the volume of the MOF is greater than the volume of the MO, the metal is suitable for use in the MOF thin film protective layer 208. Suitable metals include yttrium, gadolinium, aluminum, cerium, dysprosium, zirconium, calcium, magnesium, erbium, lanthanum, neodymium, ytterbium, and strontium. Table 1 below shows the volume increase of the MF compared to the MO for some suitable metals. [Table 1]

[0039] The MOF thin film protective layer 208 can include one or more suitable metals. Thus, the MOF thin film protective layer 208 can include one or more MOFs. For example, in one embodiment, the MOF thin film protective layer 208 is yttrium oxyfluoride. In another embodiment, the MOF thin film protective layer 208 is a combination of yttrium oxyfluoride and zirconium oxyfluoride. In such an embodiment, the metal of the MOF thin film protective layer 208 can include about 20-30% zirconium.

[0040] The MOF thin film protective layer 208 has an empirical formula M x O y F z and the empirical formula represents one molecular unit of the MOF thin film protective layer 208. The subscripts represent the relative amounts of each constituent metal, oxygen, or fluorine atom. Thus, x represents the number of metal atoms in one molecular unit of the MOF thin film protective layer 208, y represents the number of oxygen atoms in one molecular unit of the MOF thin film protective layer 208, and z represents the number of fluorine atoms in one molecular unit of the MOF thin film protective layer 208.

[0041] The empirical formula depends on the valence of the metal, or the number of electrons that the metal can accept from oxygen and fluorine atoms. Each oxygen molecule typically contributes two electrons, and each fluorine atom typically contributes one electron. Depending on the type, the metal can accept up to four electrons. Thus, depending on the metal, the value of y (i.e., the number of oxygen atoms) can range from 0.1 to 1.9 times the value of x. Similarly, the value of z (i.e., the number of fluorine atoms) can range from 0.1 to 3.9 times the value of x. One embodiment of the MOF thin film protective layer 208 is yttrium oxyfluoride, which has an empirical formula of YOF (note: the subscript is omitted when the value is 1). Another embodiment of the MOF thin film protective layer 208 is yttrium oxyfluoride with a low fluoride concentration. Such MOF thin films can be, for example, YO 1.4 F 0.2 In such a configuration, on average, there are 1.4 oxygen atoms per yttrium atom and 0.2 fluorine atoms per yttrium atom. Conversely, one embodiment of the MOF thin film protective layer 208 is yttrium oxyfluoride, which has a high fluoride concentration. Such MOF thin films can be, for example, YO 0.1 F 2.8 In such a configuration, on average, there are 0.1 oxygen atoms per yttrium atom and 2.8 fluorine atoms per yttrium atom.

[0042] The ratio of metal to oxygen and fluorine in a MOF thin film can also be expressed in atomic percentages. For example, for a metal with a valence of +3, a minimum oxygen content of 10 atomic percent corresponds to a maximum fluorine concentration of 63 atomic percent. Conversely, for the same metal with a valence of +3, a minimum fluorine content of 10 atomic percent corresponds to a maximum oxygen concentration of 52 atomic percent. Thus, for a metal with a valence of +3, the MOF thin film can have about 27-38 atomic % metal(s), 10-52 atomic % oxygen, and about 10-63 atomic % fluorine. In one embodiment, the MOF thin film has 32-34 atomic % metal(s), 30-36 atomic % oxygen, and 30-38 atomic % fluorine.

[0043] For metals with a valence of +2, the MOF thin film can have about 37-48 atomic % metal, 10-43 atomic % oxygen, and about 10-53 atomic % fluorine. In one embodiment, the MOF thin film has 40-45 atomic % metal (or metals), 20-35 atomic % oxygen, and 20-40 atomic % fluorine.

[0044] For metals with a valence of +4, the MOF thin film can have about 22-32 atomic % metal, about 10-58 atomic % oxygen, and about 10-68 atomic % fluorine. In one embodiment, the MOF thin film has 26-28 atomic % metal(s), 30-42 atomic % oxygen, and 30-44 atomic % fluorine.

[0045] The reflectance of the MOF thin film protective layer 208 ranges from transparent in one embodiment to opaque in another embodiment. The MOF thin film protective layer 208 has an effective operating temperature range of about 15° C. to 500° C. The breakdown voltage of a 10 micron MOF thin film protective layer is about 500 volts in an embodiment. The MOF thin film protective layer 208 also benefits from a higher hardness when compared to its MF counterpart. For example, YF3 has a Vickers hardness in the range of 2.74 to 3.15 gigapascals (GPa). YOF has a hardness greater than 3.15 GPa.

[0046] MOs such as yttria (yttrium oxide) are structurally crystalline, while the corresponding MF, yttrium fluoride, may be amorphous. Depending on the method and temperature used for deposition, the MOF thin film protective layer 208 may be amorphous in some embodiments and at least partially crystalline in other embodiments. Despite the various lattice structures available in different embodiments, the structure of the MOF thin film protective layer 208 is generally uniform.

[0047] 3A and 3B generally illustrate deposition mechanisms applicable to various deposition techniques (e.g., IAD or PVD). Exemplary IAD methods include deposition processes that incorporate ion bombardment, such as evaporation in the presence of ion bombardment (e.g., activated reactive evaporation (ARE) or electron beam ion assisted deposition (EB-IAD)) and sputtering (e.g., ion beam sputtering ion assisted deposition (IBS-IAD)) to form plasma resistant coatings as described herein. EB-IAD can be performed by evaporation. IBS-IAD can be performed by sputtering a solid target material (e.g., a solid metal target). Any of the IAD methods can be performed in the presence of reactive gas species (e.g., O2, N2, halogens, etc.). Alternatively, PVD can be performed without ion assistance.

[0048] As shown, the MOF thin film protective layer 315 is formed by accumulation of deposition material 302 in the presence of energetic particles 303 (e.g., ions or radicals). The deposition material 302 can include atoms, ions, radicals, or a mixture thereof. For example, the deposition material 302 can include sputtered or evaporated atoms and molecules in some embodiments. The energetic particles 303 can impact and compress as the MOF thin film protective layer 315 is formed. Additionally, the energetic particles 303 can interact with the deposition material to form the MOF thin film protective layer 315.

[0049] FIG. 3B shows a schematic diagram of an IAD deposition apparatus. As shown, a material source 352 provides a flux of deposition material 302, while an energetic particle source 355 provides a flux of energetic particles 303, both of which bombard the article 350 through the IAD process. The energetic particle source 355 may be oxygen, fluorine, and / or other material sources (e.g., argon). Additionally, multiple different energetic particle sources may be used. For example, an oxygen energetic particle source and a fluorine energetic particle source may be used. The material source (e.g., target body) 352 used to provide the deposition material 302 may be a bulk sintered ceramic that corresponds to the same ceramic of which the thin film protective layer 315 is composed. For example, the material source 352 may be a bulk sintered YOF. In some embodiments, the material source 352 may provide a portion of the material of the MOF thin film protective layer 315. For example, the material source 352 may consist of only metal for the MOF thin film protective layer 315. In the case where the MOF thin film protective layer 315 includes multiple metals (e.g., yttrium and zirconium), the material source 352 may be a metal alloy. Alternatively, two different metal material sources may be used. In such an embodiment, the particle source 355 provides oxygen atoms and fluorine atoms for the MOF thin film protective layer 315. As another example, the material source 352 may be comprised of a MF (e.g., bulk sintered YF3). In such an embodiment, the particle source 355 provides oxygen atoms for the MOF thin film protective layer 315. In the case where the MOF thin film protective layer 315 includes multiple metals, the MF material source 352 may be a fluoride containing both metals. Alternatively, two different MF material sources may be used. As yet another example, the material source 352 may be comprised of a MO (e.g., YO3). In such an embodiment, the particle source 355 provides fluorine atoms for the MOF thin film protective layer 315. In the case where the MOF thin film protective layer 315 includes multiple metals, the MO material source 352 may be an oxide containing both metals. Alternatively, two different MO material sources may be used.

[0050] The IAD can use one or more plasmas or beams to provide the material and a source of energetic ions. Also, reactive species can be provided during deposition of the plasma resistant coating. In one embodiment, the energetic particles 303 include at least one of a non-reactive species (e.g., Ar) or a reactive species (e.g., O, F). In a further embodiment, reactive species (e.g., CO and halogens (Cl, F, Br, etc.)) can be introduced during formation of the plasma resistant coating to further increase the tendency to selectively remove the deposited material that is most weakly bonded to the thin protective layer 315.

[0051] In an IAD process, the energetic particles 303 can be controlled by an energetic ion (or other particle) source 355, independent of other deposition parameters. The energy (e.g., velocity), density, and incidence angle of the energetic ion flux can manipulate the composition, structure, crystal orientation, and grain size of the thin protective layer. Additional parameters that can be adjusted are the temperature of the article during deposition and the deposition time.

[0052] Ion assist energy is used to densify the coating and accelerate the deposition of material onto the surface of the substrate. Ion assist energy can be varied using both the voltage and current of the ion source. The voltage and current can be adjusted to achieve high and low coating densities, manipulate the coating stress and the coating crystallinity. Ion assist energy can range from about 50 to 800 V and about 1 to 50 amperes (A). Ion assist energy can also be used to purposefully change the stoichiometry of the coating. For example, a metal target can be used during deposition and converted to a metal oxyfluoride.

[0053] The coating temperature can be controlled by heating the deposition chamber and / or the article using a heater and adjusting the deposition rate. The temperature of the article during deposition can be broadly divided into low temperatures (in one embodiment, about 70 to 150° C.) and high temperatures (in one embodiment, 150° C. or higher). The deposition temperature can be used to adjust the film stress, crystallinity, and other coating properties.

[0054] The working distance is the distance between the electron beam (or ion beam) gun and the article. The working distance can be varied to achieve a coating with the best uniformity. In addition, the working distance can affect the deposition rate and density of the coating.

[0055] The deposition angle is the angle between the electron beam (or ion beam) and the article. The deposition angle can be varied by changing the position and / or orientation of the substrate. By optimizing the deposition angle, uniform coating on three-dimensional features can be achieved.

[0056] EB-IAD and IBS-IAD deposition is feasible over a wide range of surface conditions. Polished surfaces can be excellent for achieving uniform coating coverage. A variety of fixtures can be used to hold the substrate during IAD deposition.

[0057] FIG. 4 illustrates one embodiment of a method 400 for forming a MOF thin film protective coating. At block 410, a MOF source material is provided. The MOF source material may be M x O y_source F z_sourceThe metal has an empirical formula of: y_source has a value between 0.1 and 1.9 times the value of x, and z_source has a value between 0.1 and 3.9 times the value of x. For example, in one embodiment, the source material is YOF. In other embodiments, other MOF source materials are used. In each embodiment, the MOF exhibits an increased volume compared to the corresponding MO. That is, a metal is suitable for use in the MOF thin film protective layer 208 if the volume of the MOF is greater than the volume of the MO. Suitable metals include yttrium, gadolinium, aluminum, cerium, dysprosium, zirconium, calcium, magnesium, erbium, lanthanum, neodymium, ytterbium, and strontium.

[0058] In block 420, the MOF source material is deposited by sputtering or evaporation to form a MOF coating on the article. x O y_coating F z_coating where y_coating has a value of 0.1 to 1.9 times the value of x, and z_coating has a value of 0.1 to 3.9 times the value of x. x O y_source F z_source and M. x O y_coating F z_coating are the same, y_source is equal to y_coating, and z_source is equal to z_coating. x O y_coating F z_coating At block 420, M is formed by introducing one or more of oxygen or fluoride ions or radicals during deposition. x O y_source F z_source can be adjusted for.

[0059] Deposition can be performed using the apparatus shown in Figure 3B. The article can be any of the semiconductor process chamber components described with respect to Figure 1. For example, the article can be any component of an Applied Centris™ Sym3™ etch system manufactured by Applied Materials, Inc., or an Applied Producer™ etch system manufactured by Applied Materials, Inc. More generally, the article can be any article that is exposed to high energy plasma or reactive gas environments that can cause erosion and degradation of the article.

[0060] The deposition in block 420 can further include heating the article to 15-150° C. In some embodiments, the article is heated prior to deposition, the MOF coating is formed on the article, and then the article and MOF coating are cooled. Additionally, in some embodiments, the deposition in block 420 is performed in a vacuum chamber. The pressure in the vacuum chamber can be initially reduced to a fraction of a mTorr (e.g., 0.1 mTorr). Gases for deposition are introduced into the chamber, and the chamber pressure is maintained at 0.1-100 mTorr. In some embodiments, the resulting MOF thin film protective coating has a thickness of 1-30 microns and a porosity of less than 0.1%. In some embodiments, the MOF thin film protective coating has a thickness of less than 20 microns. In other embodiments, the MOF thin film protective coating has a thickness of about 10 microns.

[0061] In a particular embodiment of the method 400, at block 410, a bulk sintered YOF source material and a semiconductor process chamber component are provided in a vacuum chamber. At block 420, the vacuum chamber is sealed and the pressure in the vacuum chamber is reduced to about 0.1 mTorr. The semiconductor process chamber component is heated to about 150° C. At block 420, the YOF source material is evaporated onto the semiconductor process chamber component to form a thin film protective layer. Alternatively, the YOF source material can be sputtered onto the semiconductor process chamber component. Once a target thickness of the thin film is reached, the semiconductor process chamber component and the YOF thin film protective layer are cooled.

[0062] 5A-5C illustrate methods 500, 520, 540 for forming a MOF thin film protective coating. In general, the methods 500, 520, 540 include providing a metal-containing source material and sputtering or evaporating the source material in the presence of reactive ions and radicals to form the MOF thin film protective coating on the article. The methods 500, 520, 540 can be performed in a vacuum chamber. In some embodiments, the vacuum chamber is evacuated to a fraction of a mTorr and the chamber is maintained at 0.1-100 mTorr during deposition. Additionally, in some embodiments, the article is heated to 15-150° C. and cooled after the MOF thin film protective coating is deposited.

[0063] FIG. 5A illustrates method 500. In block 505, a metal source material is provided. The metal source material may be any metal suitable for forming a MOF thin film protective coating, as described above with respect to FIG. 1. For example, suitable metals include yttrium, gadolinium, aluminum, cerium, dysprosium, zirconium, calcium, magnesium, erbium, lanthanum, neodymium, ytterbium, and strontium, or alloys or combinations thereof. In block 510, the metal source material is sputtered or evaporated, as can be accomplished by the apparatus shown in FIG. 3B. In block 515, oxygen and fluorine ions or radicals are introduced into the sputtered or evaporated metal source material to form a MOF thin film protective coating on an article, such as a semiconductor process chamber component. In some embodiments, introducing oxygen and fluorine ions or radicals includes bombarding the sputtered or evaporated metal with oxygen and fluorine ions or radicals (e.g., with an ion gun, or by forming a high-energy plasma in the vicinity of the article on which the MOF thin film protective coating is to be deposited, etc.). The resulting MOF thin film protective coating has the empirical formula M x O y_coating F z_coating where y_coating has a value between 0.1 and 1.9 times the value of x, and z_coating has a value between 0.1 and 3.9 times the value of x. Further, the coating has a thickness between 1 and 30 microns, and a porosity of less than 0.1%.

[0064] 5B illustrates a method 520. At block 525, the empirical formula M x F z_sourceA metal fluoride source material is provided having a Z_source value between 0.1 and 4 times the value of x. The metal may be any metal as described with respect to method 500. In one embodiment, the source material is YF3. In block 530, the metal fluoride source material is sputtered or evaporated, as may be accomplished by the apparatus shown in FIG. 3B. In block 535, oxygen ions or radicals are introduced into the sputtered or evaporated metal fluoride source material to form a MOF thin film protective coating on an article, such as a semiconductor process chamber component. In some embodiments, introducing oxygen ions or radicals includes bombarding the sputtered or evaporated metal fluoride with oxygen ions or radicals (e.g., by an ion gun or by forming a high energy plasma near the surface of the article on which the MOF thin film protective coating is being deposited). The resulting MOF thin film protective coating has an empirical formula M x O y_coating F z_coating where y_coating has a value between 0.1 and 1.9 times the value of x, and z_coating has a value between 0.1 and 3.9 times the value of x. Further, the coating has a thickness between 1 and 30 microns, and a porosity of less than 0.1%.

[0065] 5C illustrates a method 540. At block 545, the empirical formula M x O y_sourceA metal oxide source material is provided having a metal oxide content of 0.1 to 2 times the value of x, where y_source has a value between 0.1 and 2 times the value of x. The metal may be any metal as described with respect to method 500. In one embodiment, the source material is Y2O3. In block 550, the metal oxide source material is sputtered or evaporated, as may be accomplished by the apparatus shown in FIG. 3B. In block 555, fluorine ions or radicals are introduced into the sputtered or deposited metal fluoride source material to form a MOF thin film protective coating on an article, such as a semiconductor processing chamber component. In some embodiments, introducing fluorine ions or radicals includes bombarding the sputtered or deposited metal fluoride with fluorine ions or radicals (e.g., by an ion gun or by forming a high energy plasma near the surface of the article on which the MOF thin film protective coating is to be deposited). The resulting MOF thin film protective coating has an empirical formula M x O y_coating F z_coating where y_coating has a value between 0.1 and 1.9 times the value of x, and z_coating has a value between 0.1 and 3.9 times the value of x. Further, the coating has a thickness between 1 and 30 microns and a porosity of less than 0.1%.

[0066] The foregoing description sets forth numerous specific details, such as examples of specific systems, components, methods, etc., to provide a thorough understanding of some embodiments of the present invention. It will be apparent to one of ordinary skill in the art that at least some embodiments of the present invention can be practiced without these specific details. In other instances, well-known components or methods have not been described in detail or have been shown in simple block diagram form in order to avoid unnecessarily obscuring the present invention. Thus, the specific details set forth are merely exemplary. Particular embodiments may vary from these illustrative details and still be contemplated to be within the scope of the present invention.

[0067] Throughout this specification, "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". When the term "about" or "approximately" is used herein, it is intended that the nominal value presented is accurate to within ±10%.

[0068] Although the operations of the methods herein are shown and described in a particular order, the order of the operations of each method may be changed, certain operations may be performed in reverse order, and certain operations may be performed, at least in part, in parallel with other operations. In other embodiments, instructions or sub-operations of separate operations may be intermittent and / or alternating methods.

[0069] It should be understood that the above description is illustrative, and not restrictive. Many other embodiments will be apparent to those skilled in the art upon reading and understanding the above description. The scope of the present invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

[Claim 1] A thin film, M ｘ O ｙ F ｚ wherein M is a metal, y has a value of 0.1 to 1.9 times the value of x, and z has a value of 0.1 to 3.9 times the value of x; The membrane has a thickness of 1-30 microns and a porosity of less than 0.1%.

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