Yttrium-based protective film, member, and plasma processing apparatus

Abstract

Provided is an yttrium-based protective film which has excellent plasma resistance.　Provided is an yttrium-based protective film which contains yttrium and oxygen, and in which, in a Raman spectrum, there is no peak attributed to a Y2O3 crystal and having a peak top in the range of 383 cm-1 to 387 cm-1 inclusive. With respect to the yttrium-based protective film, in an X-ray diffraction pattern, there is no peak of the (111) plane of Y2O3, or the half-value width of the peak of the (111) plane of Y2O3 is 1.0° or more, and there is no peak of the (100) plane of Y2O3, or the half-value width of the peak of the (100) plane of Y2O3 is 1.0° or more.

Description

Yttrium protective film, components, and plasma processing apparatus

[0001] The present invention relates to a yttrium protective film, a component, and a plasma processing apparatus.

[0002] When manufacturing semiconductor devices, for example, the surface of a semiconductor substrate (silicon wafer) is microfabricated using dry etching with a halogen-based gas plasma inside a chamber, or the chamber from which the semiconductor substrate was removed after dry etching is cleaned using an oxygen gas plasma.

[0003] During this process, parts of the chamber exposed to the plasma may corrode and detach as particulate matter. These detached particles can adhere to the semiconductor substrate and become foreign objects that cause defects in the circuit.

[0004] Therefore, conventionally, yttrium protective films have been used to protect parts exposed to plasma, and Patent Document 1 discloses a "film mainly composed of yttrium oxide."

[0005] International Publication No. 2019 / 160121

[0006] The inventors of this invention investigated and found that conventional yttrium protective films sometimes have insufficient plasma resistance (corrosion resistance to plasma).

[0007] This invention has been made in view of the above points, and aims to provide a yttrium protective film with excellent plasma resistance.

[0008] The inventors, after diligent study, found that the above objective can be achieved by adopting the following configuration, and thus completed the present invention. That is, the present invention provides the following [1] to

[11] . [1] A material containing yttrium and oxygen, with a Raman spectrum of 383 cm⁻¹. －１ 387cm or more －１ Y with peak tops within the following range ２ O ３ A yttrium protective film in which no peaks attributable to the crystal exist. [2] In the X-ray diffraction pattern, Y ２ O ３There is no peak of the (111) plane of, or the full width at half maximum of the peak of the (111) plane of Y ２ O ３ is 1.0° or more, and there is no peak of the (100) plane of Y ２ O ３ or the full width at half maximum of the peak of the (100) plane of Y ２ O ３ is 1.0° or more. The yttrium-based protective film according to [1] above. [3] The yttrium-based protective film according to [1] or [2] above, wherein the content ratio of yttrium to the total of yttrium and oxygen is 35 atomic % or more and 45 atomic % or less. [4] The yttrium-based protective film according to any one of [1] to [3] above, wherein the content ratio of oxygen to the total of yttrium and oxygen is 55 atomic % or more and 65 atomic % or less. [5] The yttrium-based protective film according to any one of [1] to [4] above, wherein the total content of yttrium and oxygen is 85 atomic % or more. [6] The yttrium-based protective film according to any one of [1] to [5] above, further containing at least one element selected from the group consisting of scandium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. [7] The L ＊ value is 85 or less, the a ＊ value is 1 or more, and the b ＊ value is 1 or more. The yttrium-based protective film according to any one of [1] to [6] above. [8] The yttrium-based protective film according to any one of [1] to [7] above, having a nanoindentation hardness of 3.0 GPa or more. [9] The yttrium-based protective film according to any one of [1] to [8] above, having a surface roughness of 40.00 nm or less in terms of arithmetic mean height Sa.

[10] A member including a base material and the yttrium-based protective film according to any one of [1] to [9] above in this order.

[11] A plasma processing apparatus including the member according to

[10] above as a component constituting the inner surface.

[0009] According to the present invention, a yttrium-based protective film excellent in plasma resistance can be provided.

[0010] This is a schematic diagram showing an example of a component.

[0011] The meanings of terms used in this invention are as follows: A numerical range represented using "~" means a range that includes the numbers written before and after "~" as the lower and upper limits, respectively.

[0012] [Yttrium protective film] The yttrium protective film of this embodiment contains yttrium and oxygen, and in the Raman spectrum, it shows 383 cm⁻¹. －１ 387cm or more －１ Y with peak tops within the following range ２ O ３ Peaks attributed to the crystal (hereinafter referred to as "Y") ２ O ３ The yttrium protective film of this embodiment does not exhibit a "crystal peak" (which is called a crystal peak). The yttrium protective film of this embodiment has excellent plasma resistance. The reason for this is not clear, but it is presumed to be as follows.

[0013] The yttrium protective film of this embodiment contains yttrium and oxygen, i.e., yttrium oxide. ２ O ３ The absence of crystalline peaks indicates that the yttrium oxide is undergoing non-orientation (non-crystallization), which suppresses embrittlement in the yttrium protective film of this embodiment, resulting in excellent plasma resistance.

[0014] The yttrium protective film of this embodiment will be described in more detail below.

[0015] <Raman Spectrum> As described above, the yttrium protective film of this embodiment shows Y in the Raman spectrum. ２ O ３ Crystal peak (383 cm) －１ 387cm or more －１ No peaks with peak tops exist within the following range: Y ２ O ３ The absence of a crystal peak means that there is no peak at 340 cm. －１ 383 cm² relative to the peak intensity (Ia) at －１ 387cm or more －１This means that the ratio of peak intensities (Ib) to peaks with peak tops within the following range (Ib / Ia) is 4.0 or less.

[0016] The Raman spectrum of the yttrium protective film is obtained by performing Raman spectroscopy measurements using a micro-laser Raman spectrometer (LabRAM HR800, Horiba, Ltd.) under the following conditions: • Excitation light wavelength: 532 nm • Excitation light irradiation diameter: 2.5 μm • Excitation light output: 400 mW • Slit width: 100 μm • Grating: 600 g / mm

[0017] <XRD pattern> Yttrium oxide (Y ２ O ３ The crystal of ) shows peaks at specific locations (ranges) in the X-ray diffraction (XRD) chart that are attributed to specific planes. ２ O ３ The peak (Y) of the (111) plane ２ O ３ The 111 diffraction peak appears at 2θ = 26.3–29.7°. ２ O ３ The peak (Y) of the (100) plane ２ O ３ The 100-degree diffraction peak appears at 2θ = 35.3–34.7°.

[0018] For convenience, the following will be referred to as "Y ２ O ３ The peak of the (111) plane is "Y ２ O ３ (111) It is called the peak and "Y ２ O ３ The peak of the (100) plane is "Y ２ O ３ It is called the (100) peak.

[0019] The yttrium protective film of this embodiment has a Y in the XRD pattern. ２ O ３ (111) No peak exists, or Y ２ O ３(111) It is preferable that the full width at half maximum (FWHM) of the peak is 1.0° or more at 2θ. In this case, noncrystallization is progressing, and plasma resistance is better. For similar reasons, the yttrium protective film of this embodiment is Y ２ O ３ (100) No peak exists, or Y ２ O ３ (100) It is preferable that the full width at half maximum (full width at half maximum) of the peak is 1.0° or more at 2θ.

[0020] The XRD pattern of the yttrium protective film is obtained by performing a standard measurement using the Out-of-Plane method with a desktop X-ray diffractometer (MiniFlex, Rigaku Corporation) under the following conditions: • X-ray source: CuKα (output: 45kV, current: 40mA) • Scanning range: 2θ = 10 to 80° • Step time: 0.4° / step • Scan speed: 10° / min • Step width: 0.02° • Incident optical system: 1.0mmφ microslit

[0021] <Crystallite Size> Due to the progression of noncrystallization and the resulting superior plasma resistance, the crystallite size of the yttrium protective film is preferably 5.0 nm or less, more preferably 4.5 nm or less, even more preferably 4.0 nm or less, and particularly preferably 3.5 nm or less. The crystallite size is determined by the Y in the XRD pattern of the yttrium protective film. ２ O ３ (111) Based on the peak, calculate using Scherrer's formula.

[0022] <Optical Bandgap> The optical bandgap of the yttrium protective film in this embodiment is preferably 5.0 eV or less, more preferably 4.7 eV or less, even more preferably 4.3 eV or less, particularly preferably 3.8 eV or less, and most preferably 3.4 eV or less, for the reason of superior plasma resistance. On the other hand, the optical bandgap of the yttrium protective film in this embodiment may be, for example, 2.8 eV or more, and may also be 3.0 eV or more.

[0023] The optical band gap of the yttrium protective film is determined as follows. First, the transmittance spectrum (vertical axis: transmittance T (unit: %), horizontal axis: wavelength (unit: nm)) and reflectance spectrum (vertical axis: reflectance R (unit: %), horizontal axis: wavelength (unit: nm)) of the yttrium protective film are determined under the following conditions: • Measurement device: UV-Vis-Near Infrared Spectrophotometer (V-770, manufactured by JASCO Corporation) • Measurement wavelength range: 300-600 nm • Scan speed: 400 nm / min • Incident angle: 5 degrees • Detection angle: 0 degrees Note that, for example, if the substrate on which the yttrium protective film is placed is a ceramic or other material that causes scattering, spectral measurement by transmission is difficult, so total internal reflection (ATR) measurement is used. However, if the yttrium protective film has a certain thickness, the yttrium protective film may be peeled from the substrate, thinned, and then spectrally measured using the transmission method.

[0024] Next, the film thickness d (in cm) of the yttrium protective film is determined under the following conditions: • Measuring device: Stylus-type surface shape analyzer (Dektak-XT, Bruker) • Scanning speed: 10 seconds • Scanning distance: 1000 μm • Measurement range: 6.5 μm

[0025] Furthermore, based on the following equation obtained by modifying the Lambert-Beer law, the absorption coefficient α (unit: cm) is calculated. －１ ) is calculated to obtain the absorption coefficient spectrum. α = (1 / d)log((100-R) / T)

[0026] Then, the logarithm of the absorption coefficient α is plotted on the vertical axis, and the reciprocal of the energy E (= hc / λ) is 1 / E (unit: eV). －１ Create a spectrum with ) on the horizontal axis. Add 1 / E = 0.25 eV to the created spectrum. －１ The point and 1 / E = 0.28 eV －１ A straight line L1 passes through the point and, 1 / E = 0.4eV －１ A line L2 parallel to the horizontal axis is added, passing through the point. Then, the value of 1 / E of the spectrum at the intersection of line L1 and line L2 is read, and its reciprocal is obtained as the optical band gap (unit: eV).

[0027] <Composition> The yttrium protective film contains yttrium (Y) and oxygen (O). The total content of Y and O in the yttrium protective film is preferably 85 atomic% or more, more preferably 90 atomic% or more, and even more preferably 95 atomic% or more. The upper limit is not particularly limited and may be 100 atomic%. When the yttrium protective film is manufactured by the method described later, it shall satisfy the above composition.

[0028] The yttrium protective film contains, for example, yttrium oxide. ２ O ３ Theoretically, the Y and O content in yttrium oxide, represented by [formula], is 40 atomic% and 60 atomic%. Therefore, in the yttrium protective film, the ratio of Y to the total of Y and O (hereinafter referred to as "Y / (Y+O)") may be, for example, 35 atomic% or more, 38 atomic% or more, or, for example, 45 atomic% or less, or 42 atomic% or less. Also, in the yttrium protective film, the ratio of O to the total of Y and O (hereinafter referred to as "O / (Y+O)") may be, for example, 55 atomic% or more, 58 atomic% or more, or, for example, 65 atomic% or less, or 62 atomic% or less.

[0029] However, yttrium oxide produced by the method described later tends to be a suboxide. That is, the yttrium oxide contained in the yttrium protective film of this embodiment tends to have a higher Y content and a lower O content than the theoretical values. For this reason, in the yttrium protective film, Y / (Y+O) may be 41 atomic percent or more. Also, in the yttrium protective film, O / (Y+O) may be 59 atomic percent or less.

[0030] The yttrium protective film may contain, in addition to Y and O, other rare earth elements other than Y. That is, the yttrium protective film may contain at least one element selected from the group consisting of scandium (Sc), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu) (hereinafter referred to as "additive element"). The content of the additive element in the yttrium protective film is preferably 5 atomic percent or less, more preferably 3 atomic percent or less, even more preferably 1 atomic percent or less, and may be 0 atomic percent. Furthermore, the aluminum (Al) content in the yttrium protective film is preferably 5 atomic percent or less, more preferably 3 atomic percent or less, even more preferably 1 atomic percent or less, and may even be 0 atomic percent.

[0031] The content of each element in the yttrium protective film is determined using an energy-dispersive X-ray analyzer (EDX) attached to a scanning electron microscope (SEM).

[0032] <L ＊ a ＊ b ＊ > Next, the yttrium protective film L ＊ Value, a ＊ Value and b ＊ Let's explain the value. L ＊ Value, a ＊ Value and b ＊ The values ​​are, respectively, CIE1976L ＊ a ＊ b ＊ L in color space ＊ a ＊ and b ＊ Therefore, measurements are taken using a spectrophotometer (CM-5, manufactured by Konica Minolta) with the SCE (Specular Reflectance Rejection) method and a D65 light source.

[0033] L ＊The value is, for example, 90 or less, preferably less than 89, more preferably 85 or less, even more preferably 70 or less, particularly preferably 50 or less, and most preferably 35 or less. On the other hand, regarding the lower limit, L ＊ The value is, for example, 10 or more, preferably 15 or more, and more preferably 20 or more.

[0034] a ＊ The value is, for example, -5 or greater, preferably -2 or greater, more preferably 1 or greater, even more preferably 5 or greater, particularly preferably 10 or greater, and most preferably 15 or greater. On the other hand, regarding the upper limit, a ＊ The value is, for example, 35 or less, preferably 30 or less, and more preferably 25 or less.

[0035] b ＊ The value is, for example, -5 or greater, preferably -2 or greater, more preferably 1 or greater, even more preferably 8 or greater, particularly preferably 17 or greater, and most preferably 25 or greater. On the other hand, regarding the upper limit, b ＊ The value is, for example, 50 or less, preferably 45 or less, and more preferably 40 or less.

[0036] <Nanoindentation Hardness> The nanoindentation hardness of the yttrium protective film is preferably 3.0 GPa or higher, more preferably 4.5 GPa or higher, even more preferably 6.0 GPa or higher, particularly preferably 7.5 GPa or higher, and most preferably 9.0 GPa or higher, because it provides superior plasma resistance. In this case, the yttrium protective film is densified, and therefore is presumed to have high hardness. There is no particular upper limit, and the nanoindentation hardness of the yttrium protective film may be, for example, 14.0 GPa or less, 12.0 GPa or less, or 10.0 GPa or less.

[0037] The nanoindentation hardness of the yttrium protective film is measured using a nanoindentation tester, varying the load between 0 and 50 mN. Measurements are taken at 20 locations, and the average value is adopted as the nanoindentation hardness. Other test conditions are as follows: A KLA iMicro nanoindentation tester is used, and the sample (yttrium protective film placed on the surface of the substrate) is fixed to its sample stage. For sample fixation, a thermoplastic temporary adhesive "Crystalbond 555" (fluidization temperature: 48°C) manufactured by Alemco is used. As the actuator, an "inForce 50" that can be used with loads up to 50 mN is selected. As the indenter, a Berkovich indenter with a triangular pyramidal tip (tip radius of curvature: 20 nm) is used.

[0038] <Surface Roughness (Sa)> The surface roughness of the yttrium protective film is, for example, 50.00 nm or less in arithmetic mean height Sa, preferably 40.00 nm or less, more preferably 30.00 nm or less, even more preferably 25.00 nm or less, and particularly preferably 20.00 nm or less, in terms of superior plasma resistance. On the other hand, the lower limit is not particularly limited. The surface roughness (Sa) of the yttrium protective film is, for example, 5.00 nm or more, and may be 10.00 nm or more. The surface roughness (Sa) is measured using a VK-X3000 (manufactured by Keyence Corporation) in accordance with ISO 25178. The average of two measured values ​​is adopted as the surface roughness (Sa) value.

[0039] <Porosity> The porosity of the yttrium protective film is preferably less than 0.40 volume%, more preferably 0.30 volume% or less, even more preferably 0.20 volume% or less, and particularly preferably 0.10 volume% or less. The porosity of the yttrium protective film may be 0.00 volume% or more, and is often 0.001 volume% or more. When the film is formed by thermal spraying, the porosity of the yttrium protective film is often 0.40 volume% or more. By manufacturing the yttrium protective film using the method described later, the porosity can be adjusted to the above preferred range.

[0040] In this specification, the porosity of the yttrium protective film is determined as follows. First, using a focused ion beam (FIB), a slope is applied to the yttrium protective film and a portion of the substrate described later, at a 52° angle in the thickness direction from the surface of the yttrium protective film toward the substrate, to expose the cross-section. The exposed cross-section is observed at a magnification of 20,000x using a field emission scanning electron microscope (FE-SEM), and a cross-sectional image is taken. Cross-sectional images are taken at multiple locations. Specifically, for example, if the yttrium protective film is circular, images are taken at a total of five points: one point in the center of the surface of the yttrium protective film and four points located 10 mm away from the outer edge, with the size of the cross-sectional image being 6 μm × 5 μm. If the thickness of the yttrium protective film is 5 μm or more, cross-sectional images are taken at multiple locations so that the entire cross-section of the yttrium protective film can be observed in the thickness direction. Next, the obtained cross-sectional images are analyzed using image analysis software (ImageJ, manufactured by the National Institute of Health) to identify the area of ​​pores in the cross-sectional images. The ratio of the area of ​​pores to the total cross-sectional area of ​​the yttrium protective film is calculated and considered to be the porosity (unit: volume %) of the yttrium protective film. Note that pores that are too fine to be detected by the image analysis software (pores with a diameter of 20 nm or less) are considered to have an area of ​​0.

[0041] <Thickness> The thickness of the yttrium protective film is, for example, 0.3 μm or more, preferably 1.0 μm or more, more preferably 1.5 μm or more, even more preferably 5.0 μm or more, and particularly preferably 10.0 μm or more. On the other hand, the thickness of the yttrium protective film is, for example, 300.0 μm or less, preferably 200.0 μm or less, more preferably 100.0 μm or less, even more preferably 50.0 μm or less, and particularly preferably 30.0 μm or less.

[0042] The thickness of the yttrium-based protective film is measured using a scanning electron microscope (SEM). More specifically, the cross-section of the yttrium-based protective film is observed, and the thickness of the yttrium-based protective film is measured at any five points, and the average value of the five measured points is determined as the thickness (unit: μm) of this yttrium-based protective film.

[0043] [Members] Next, the members of this embodiment will be described. First, based on FIG. 1, the members of this embodiment will be schematically described.

[0044] FIG. 1 is a schematic diagram showing an example of the member 1. As shown in FIG. 1, in the member 1, the yttrium-based protective film 2 is formed on the film-forming surface 3a which is one surface of the base material 3. That is, the member 1 has the base material 3 and the yttrium-based protective film 2 in this order. As the yttrium-based protective film 2, the yttrium-based protective film of this embodiment described above is used. The base material 3 will be described later.

[0045] <Base Material> The material of the base material is appropriately selected according to the use of the member and the like. The base material is composed of, for example, at least one selected from the group consisting of carbon (C), ceramics, and metals. The ceramics are, for example, glass (such as soda lime glass), quartz, aluminum oxide (Al ２ O ３ ), aluminum nitride (AlN), cordierite, yttrium oxide, silicon carbide (SiC), Si-impregnated silicon carbide, silicon nitride (SiN), sialon, and aluminum oxynitride (AlON). Si-impregnated silicon carbide is obtained by heating and melting Si and impregnating it into silicon carbide (SiC). The metal is, for example, at least one selected from the group consisting of aluminum (Al) and alloys containing aluminum (Al).

[0046] The shape of the base material is not particularly limited, and examples include a flat plate shape, a disc shape, a ring shape, a dome shape, a concave shape, or a convex shape, and is appropriately selected according to the use of the member and the like. The base material may have a through hole in a part thereof, or may be chamfered.

[0047] As described above, the substrate has a surface (film-forming surface) on which the yttrium protective film is formed. The smaller the surface roughness of the film-forming surface of the substrate, the smaller the surface roughness of the yttrium protective film formed on the film-forming surface tends to be. For this reason, it is preferable that the film-forming surface of the substrate has a surface roughness (Sa) similar to that of the yttrium protective film that is formed.

[0048] <Applications of the components> The components are used, for example, as parts that constitute a plasma processing apparatus, particularly as parts such as top plates that constitute the inner surface of the plasma processing apparatus. In other words, the yttrium protective film is preferably a yttrium protective film for use in a plasma processing apparatus. Examples of plasma processing apparatuses include plasma etching apparatuses, plasma CVD apparatuses, plasma ALD apparatuses, and plasma modification apparatuses, and these apparatuses are used, for example, in the manufacture of semiconductor devices. However, the applications are not limited to these.

[0049] [Method for Manufacturing the Yttrium Protective Film and Components] Next, a method for manufacturing the yttrium protective film of this embodiment will be described. The following description also serves as a description of the method for manufacturing the components of this embodiment.

[0050] The yttrium protective film is formed on the film-forming surface of the substrate using a film-forming method such as sputtering or vapor deposition. Specific examples of film-forming methods include DPDS (Digitally Processed DC Sputtering), reactive sputtering, IAD (Ion-Assisted Vapor Deposition), and ion plating. Among these, DPDS and IAD are preferred, with DPDS being more preferred.

[0051] The DPDS method is a method for obtaining a desired film by repeatedly alternating between forming a thin metal film and contacting the formed thin metal film with a reactive gas. By using the DPDS method, it is easy to obtain a yttrium protective film that satisfies the above requirements. Furthermore, the resulting yttrium protective film is less prone to the formation of an altered layer after etching.

[0052] The following describes a method for forming a yttrium protective film using the DPDS method. When forming a yttrium protective film using the DPDS method, it is preferable to alternately repeat the formation of a metal thin film (a film containing metallic yttrium) and the oxidation of the formed metal thin film. The formation of the metal thin film and the oxidation of the metal thin film may be carried out using separate chambers (not shown).

[0053] Specifically, for example, first, the substrate is placed in a first chamber with an inert gas atmosphere (e.g., argon gas). Then, a metal thin film is formed on the deposition surface of the substrate using a sputtering target made of metallic yttrium. The thickness of the metal thin film in a single formation is in the sub-nm range.

[0054] Next, the substrate on which the metal thin film is formed is transferred to a second chamber with a mixed gas atmosphere of inert gas and oxygen gas to oxidize the metal thin film. The ratio of the amount of oxygen gas supplied to the total amount of inert gas and oxygen gas supplied (hereinafter referred to as the "oxygen gas ratio") is adjusted as appropriate, but may be, for example, 20% by volume or more, or 30% by volume or more. On the other hand, the oxygen gas ratio may be, for example, 80% by volume or less, or 70% by volume or less.

[0055] When forming and oxidizing metal thin films, for example, a plasma is generated by applying an electric field between the anode and cathode in the chamber while controlling the temperature and pressure inside the chamber, and then sputtering is performed.

[0056] The temperature inside the chamber is, for example, 180°C or lower, preferably 150°C or lower, more preferably 120°C or lower, and even more preferably 100°C or lower. On the other hand, the temperature inside the chamber is, for example, 10°C or higher, and may be 20°C or higher.

[0057] The pressure inside the chamber is preferably 0.20 Pa or less, more preferably 0.15 Pa or less, even more preferably 0.12 Pa or less, and particularly preferably 0.10 Pa or less. On the other hand, the pressure inside the chamber is, for example, 0.01 Pa or more.

[0058] Examples of plasma types include capacitively coupled plasma (CCP), inductively coupled plasma (ICP), and electron cyclotron resonance plasma (ECR plasma), with CCP or ICP being preferred, and CCP being more preferred.

[0059] By repeatedly forming and oxidizing thin metal films alternately, and by stacking the oxidized thin metal films to a desired thickness, a yttrium-based protective film containing Y and O is formed.

[0060] Thus, a component comprising a yttrium protective film and a substrate is obtained. Because the obtained component has excellent plasma resistance, it is suitably used as a component constituting the inner surface of a plasma processing apparatus, as described above.

[0061] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the examples described below. Examples 1 and 2 are examples, and Example 3 is a comparative example.

[0062] <Manufacturing of Components> A yttrium protective film (thickness: 10 μm) containing Y and O was formed on the film-forming surface of a flat substrate (material: aluminum oxide, surface roughness Sa of the film-forming surface: 40.00 nm) using a sputtering apparatus (CCS-2800, manufactured by Shibaura Mechatronics Co., Ltd.) by the DPDS method described above. At this time, argon gas was used as the inert gas, and the oxygen gas ratio was 50 volume%. The types of plasma (CCP or ICP) shown in Table 1 below were generated, and the temperature and pressure in the chamber were controlled to the values ​​shown in Table 1 below. Two sputtering apparatuses were prepared, one equipped with a plasma gun for generating CCP and the other with a plasma gun for generating ICP, and one was used depending on the type of plasma to be generated. In this way, components consisting of a yttrium protective film and a substrate were obtained.

[0063] In all examples, the total content of Y and O in the formed yttrium protective film was 99 atomic percent or more.

[0064] The following parameters were determined for the formed yttrium protective film using the method described above. The results are shown in Table 1 below. Note that the Y value of the Raman spectrum is also shown.２ O ３ Regarding the crystal peak, when the peak did not exist, "A" was described in Table 1 below, and when the peak existed, "B" was described. Also, for the Y of the XRD pattern ２ O ３ (111) peak and Y ２ O ３ Regarding the (100) peak, when the peak did not exist, "-" was described in the half-value width column in Table 1 below, respectively.

[0065] 〈Etching amount (plasma resistance)〉 Plasma etching was performed on the formed yttrium-based protective film to evaluate the plasma resistance. More specifically, first, the member was cut into a size of 20 mm × 20 mm × 2 mm so that the surface size of the yttrium-based protective film became 20 mm × 20 mm. Next, half of the surface was coated with a polyimide tape (P-222, manufactured by Nitto Denko Corporation) with a total thickness of 100 μm. Thus, a sample was prepared. Then, the sample was placed on the stage of a plasma etching apparatus, and plasma (CCP or ICP) was generated using a mixed gas of CF ４ / O ２ / Ar (mixing ratio: 40 / 10 / 50) to perform etching. At this time, the output was 550 W, the pressure was 3 Pa, and the etching time was 60 minutes. EXAM (manufactured by Shinko Seiki Co., Ltd.) was used when generating CCP, and RIE-101iPH (manufactured by Samco) was used when generating ICP as the plasma etching apparatus. After etching, the polyimide tape was peeled off, and the distance of the step generated between the coated surface and the exposed surface was measured using a stylus surface profiler (Dektak-XT, manufactured by Bruker). The measurement was performed at three points, and the average value of the three points was obtained as the etching amount (unit: μm). The results are shown in Table 1 below. The smaller the etching amount, the better the plasma resistance can be evaluated.

[0066]

[0067] 〈Summary of evaluation results〉 As shown in Table 1 above, for the yttrium-based protective films of Examples 1 to 2 where there are no peaks attributed to Y ２ O ３ crystals, the yttrium-based protective films of Examples 1 to 2 ２ O３ It was found that the etching amount was smaller and the plasma resistance was superior compared to Example 3, in which peaks attributable to the crystal exist. Furthermore, when the porosity of Example 1 and Example 2 was measured according to the method described above, it was less than 0.10 volume%. The entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2025-010778, filed on January 24, 2025, are incorporated herein by reference as disclosure of the present invention.

[0068] 1: Component 2: Yttrium protective film 3: Substrate 3a: Film-forming surface

Claims

1. Contains yttrium and oxygen, and in Raman spectrum, 383 cm⁻¹ －１ 387cm or more －１ Y with peak tops within the following range ２ O ３ A yttrium-based protective film with no peaks attributable to crystals.

2. In the X-ray diffraction pattern, Y ２ O ３ has no peak for the (111) plane, or the full width at half maximum of the peak for the (111) plane of Y ２ O ３ is 1.0° or more, and Y ２ O ３ has no peak for the (100) plane, or the full width at half maximum of the peak for the (100) plane of Y ２ O ３ is 1.0° or more. The yttrium-based protective film according to claim 1.

3. The yttrium protective film according to claim 1, wherein the yttrium content relative to the total amount of yttrium and oxygen is 35 atomic% or more and 45 atomic% or less.

4. The yttrium protective film according to claim 1, wherein the oxygen content relative to the total amount of yttrium and oxygen is 55 atomic% or more and 65 atomic% or less.

5. The yttrium protective film according to claim 1, wherein the total content of yttrium and oxygen is 85 atomic percent or more.

6. The yttrium protective film according to claim 1, further comprising at least one element selected from the group consisting of scandium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.

7. L ＊ The value is 85 or less, a ＊ The value is 1 or greater, b ＊ The yttrium protective film according to claim 1, wherein the value is 1 or greater.

8. The yttrium protective film according to claim 1, wherein the nanoindentation hardness is 3.0 GPa or higher.

9. The yttrium protective film according to claim 1, wherein the surface roughness is 40.00 nm or less in arithmetic mean height Sa.

10. A component comprising, in this order, a base material and a yttrium protective film according to any one of claims 1 to 9.

11. A plasma processing apparatus comprising the member described in claim 10 as a component constituting the inner surface.

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