Yttrium protective film, its manufacturing method and components

Abstract

This invention provides a yttrium protective film with excellent plasma resistance and appearance. The invention provides a yttrium protective film containing yttrium oxide, with a porosity of less than 0.5% by volume and a Vickers hardness of 800 HV or higher. Preferably, the yttrium protective film has a thickness of 0.3 μm or more, a crystallite size of 40 nm or less, an alignment degree of 50% or more for the (222) plane of Y₂O₃, a hydrogen atom number of 5.0 × 10²¹ atoms / cm³ or less, and a compressive stress of 100–1700 MPa.

Description

Technical Field

[0001] The present invention relates to an yttrium protective film and a manufacturing method and component thereof. Prior Art

[0002] When manufacturing semiconductor devices, for example, the surface of a semiconductor substrate (silicon wafer) is micro-processed in a chamber by dry etching using plasma of a halogen-based gas, or after dry etching, the chamber is cleaned using oxygen plasma after the semiconductor substrate has been removed.

[0003] At this time, components exposed to the plasma in the chamber may corrode, and the corroded parts may break off from the corroded components in the form of particles. These particles (microparticles) may adhere to the semiconductor substrate and become foreign matter that causes circuit defects.

[0004] Therefore, a protective film containing yttrium oxide (Y2O3) (yttrium protective film) has been known as a protective film for protecting components exposed to plasma. Patent Document 1 discloses a sprayed film containing yttrium oxide formed by spraying. Prior Art Literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-76546 Summary of the Invention

[0006] [Problems to be solved by the invention]

[0007] The present inventors have found through research that the existing yttrium protective film has insufficient plasma resistance (corrosion resistance to plasma).

[0008] Furthermore, the yttrium protective film may have a poor appearance (for example, cracks or wrinkles may occur in the yttrium protective film). In such cases, the yttrium protective film may not be suitable for direct use depending on the intended use.

[0009] The present invention is completed in view of the above aspects, and its purpose is to provide an yttrium protective film with excellent plasma resistance and appearance. [Technical means to solve the problem]

[0010] The present inventors have conducted intensive research and have found that the above-mentioned object can be achieved by adopting the following configuration, thereby completing the present invention.

[0011] That is, the present invention provides the following [1] to

[22] . [1] A yttrium protective film containing yttrium oxide, having a porosity of less than 0.5% by volume and a Vickers hardness of 800 HV or more. [2] The yttrium protective film described in [1] above has a thickness of 0.3 μm or more. [3] The yttrium protective film described in [1] or [2] above, having a thickness of less than 15 μm. [4] The yttrium protective film as described in any one of [1] to [3] above, wherein the crystallite size is less than 40 nm. [5] The yttrium protective film as described in any one of [1] to [4] above, wherein the crystallite size is greater than 6 nm. [6] The yttrium protective film as described in any one of [1] to [5] above, wherein the (222) orientation of the Y2O3 surface is greater than 50%. [7] The yttrium protective film as described in any one of [1] to [6] above, wherein the number of hydrogen atoms is 5.0×10 21 / cm 3 or less. [8] The yttrium protective film as described in any one of [1] to [7] above, wherein the compressive stress is 100~1700 MPa. [9] A component comprising a substrate and a yttrium protective film as described in any one of [1] to [8] above, wherein the yttrium protective film is disposed on a surface of the substrate, i.e., a film-forming surface.

[10] A component as described in [9] above, wherein the substrate contains at least one selected from the group consisting of carbon, ceramics and metals, the ceramic is at least one selected from the group consisting of glass, quartz, alumina, aluminum nitride, cordierite, yttrium oxide, silicon carbide, Si-impregnated silicon carbide, silicon nitride, sialon and aluminum oxynitride, and the metal is at least one selected from the group consisting of aluminum and alloys containing aluminum.

[11] The component as described in [9] above, wherein the substrate contains aluminum oxide.

[12] The component as described in [9] above, wherein the substrate contains quartz.

[13] A component as described in any one of [9] to

[12] above, wherein the surface roughness of the film-forming surface is less than 1.0 μm in terms of arithmetic mean roughness Ra.

[14] A component as described in any one of [9] to

[13] above, wherein the surface roughness of the film-forming surface is greater than or equal to 0.01 μm in terms of arithmetic mean roughness Ra.

[15] A component as described in any one of [9] to

[14] above, wherein the maximum length of the film-forming surface is greater than 30 mm.

[16] A component as described in any one of [9] to

[15] above, wherein there is one or more base layers between the substrate and the yttrium protective film, and the base layer contains at least one oxide selected from the group consisting of Al2O3, SiO2, Y2O3, MgO, ZrO2, La2O3, Nd2O3, Yb2O3, Eu2O3 and Gd2O3.

[17] A component as described in

[16] above, wherein there are two or more base layers between the substrate and the yttrium protective film, and the oxides in adjacent base layers are different from each other.

[18] A component as described in any one of [9] to

[17] above, wherein the substrate has a first film-forming surface that specifies the maximum length, and a second film-forming surface that is different from the first film-forming surface as the film-forming surface, the angle between the first film-forming surface and the second film-forming surface is 20° to 120°, and the ratio of the area of ​​the second film-forming surface to the total area of ​​the film-forming surface is less than 60%.

[19] A component as described in any one of [9] to

[18] above, which is used inside a plasma etching device or a plasma CVD (Chemical Vapor Deposition) device.

[20] A method for manufacturing a yttrium protective film, which is a method for manufacturing a yttrium protective film as described in any one of [1] to [8] above, wherein in a vacuum, while irradiating ions of at least one element selected from the group consisting of oxygen, argon, neon, krypton and xenon, an evaporation source is evaporated and attached to a substrate, and Y2O3 is used as the above-mentioned evaporation source.

[21] A method for manufacturing a yttrium protective film as described in

[20] above, wherein the substrate is heated at a temperature above 300°C before the evaporation source is attached to the substrate.

[22] A method for manufacturing a yttrium protective film as described in

[20] or

[21] above, wherein before the evaporation source is attached to the substrate, one or more base layers are formed on the surface of the substrate, and the base layer contains at least one oxide selected from the group consisting of Al2O3, SiO2, Y2O3, MgO, ZrO2, La2O3, Nd2O3, Yb2O3, Eu2O3 and Gd2O3. [Effects of the Invention]

[0012] According to the present invention, a yttrium protective film having excellent plasma resistance and appearance can be provided. Simple diagram description

[0013] FIG1 is a schematic diagram showing an example of a component. FIG2 is a schematic diagram showing a half-cut ring-shaped substrate. FIG3 is a schematic diagram showing a portion of the cross section of another annular substrate. FIG4 is a schematic diagram showing a portion of the cross section of another annular substrate. FIG5 is a schematic diagram showing an apparatus used in manufacturing the yttrium protective film. FIG6 shows the XRD (X-ray Diffraction) pattern of the yttrium protective film of Example 1. FIG. 7 is a SEM (Scanning Electron Microscope) photograph of the surface of the yttrium protective film of Example 1. FIG8 is a cross-sectional SEM photograph of the yttrium protective film of Example 1. Implementation Method

[0014] The meanings of the terms used in the present invention are as follows. A numerical range expressed using “~” means that the numerical values ​​before and after the “~” are included in the range as the lower limit and the upper limit.

[0015] [Yttrium protective film] The yttrium protective film of this embodiment contains yttrium oxide, has a porosity of less than 0.5% by volume, and has a Vickers hardness of 800 HV or higher.

[0016] Hereinafter, the yttrium protective film is also referred to as a "protective film" for short, and the yttrium protective film (protective film) of this embodiment is also referred to as the "present protective film". This protective film has excellent plasma resistance and appearance. Hereinafter, this protective film will be described in more detail.

[0017] <Vickers Hardness> As the reason why the protective film has excellent plasma resistance, the Vickers hardness of the protective film is 800 HV or higher, preferably 1000 HV or higher, more preferably 1100 HV or higher, further preferably 1200 HV or higher, particularly preferably 1250 HV or higher, and most preferably 1300 HV or higher. On the other hand, the Vickers hardness of the protective film is, for example, 1800 HV or less, preferably 1600 HV or less.

[0018] In order to adjust the Vickers hardness to the above range, it is preferred to produce the protective film by the method described later (this production method).

[0019] The Vickers hardness of the protective film is determined according to JIS Z 2244. More specifically, the Vickers hardness of this protective film is measured using a micro-Vickers hardness tester (HM-220, manufactured by Mitutoyo) with a diamond indenter at an angle of 136° and a test force of 0.049 N (HV 0.005).

[0020] <Porosity> In order to achieve excellent plasma resistance and appearance of the protective film, the porosity of the protective film is less than 0.5% by volume, preferably less than 0.3% by volume, more preferably less than 0.2% by volume, and even more preferably less than 0.1% by volume.

[0021] In order to adjust the porosity to the above range, it is preferred to produce the protective film by the method described later (this production method).

[0022] The porosity of the protective film is obtained as follows. First, a focused ion beam (FIB) was used to process the protective film and a portion of the substrate (described later) at an angle of 52° in the thickness direction, from the protective film surface toward the substrate, to expose a cross-section. The exposed cross-section was observed and imaged using a field emission scanning electron microscope (FE-SEM) at 20,000x magnification. Cross-sectional images are captured at multiple locations. Specifically, for example, if the protective film and substrate are circular, images are captured at five locations: one at the center of the protective film surface (or substrate surface) and four points 10 mm from the periphery. The cross-sectional image size is set to 6 μm x 5 μm. For protective films with a thickness of 5 μm or greater, cross-sectional images are captured at multiple locations to allow for observation of the entire cross-section of the protective film in the thickness direction. The obtained cross-sectional images were then analyzed using image analysis software (Image J, manufactured by the National Institute of Health) to identify the area of ​​the pores within the cross-sectional images. The ratio of the pore area to the total cross-sectional area of ​​the protective film was calculated and used as the porosity of the protective film (unit: volume %). Furthermore, for pores so fine that they could not be detected by the image analysis software (pores with a diameter of 20 nm or less), their area was considered zero.

[0023] <Composition> The present protective film contains yttrium oxide (Y2O3). The Y2O3 content of the present protective film is preferably 95% by mass or more, more preferably 98% by mass or more, and even more preferably 100% by mass. The protective film produced by the method described later (this production method) essentially contains only Y 2 O 3, and its Y 2 O 3 content should satisfy the above range.

[0024] <Orientation> When the area of ​​the protective film is increased, from the perspective of suppressing the generation of cracks (including wrinkles, the same below) in the protective film, the orientation degree of the (222) surface of the Y2O3 of the protective film (hereinafter also referred to as "orientation degree") is preferably higher. Specifically, the degree of orientation is preferably 50% or more, more preferably 65% ​​or more, and further preferably 80% or more. In order to set the orientation degree to the above range, it is preferred to manufacture the protective film by the method described later (this manufacturing method). The orientation is the ratio (unit: %) of the peak intensity of the (222) plane in the XRD pattern of the protective film (see Figure 6) when the total peak intensity of each plane of Y2O3 is set to 100.

[0025] The XRD pattern of the protective film was obtained by performing XRD measurement in a micro 2D (two-dimensional) mode using an X-ray diffraction apparatus (D8 DISCOVER Plus, manufactured by Bruker) under the following conditions. ∙X-ray source: CuKα ray (output: 45 kV, current: 120 mA) ∙Scanning range: 2θ = 10°~80° ∙Step time: 0.2 s / step Scanning speed: 10° / min ∙Step width: 0.02° ∙Detector: Multi-mode detector EIGER (2D mode) ∙ Incident side optical system: multilayer mirror + 1.0 mm ϕ micro slit + 1.0 mm ϕ collimator ∙ Optical system on the light receiving side: Open

[0026] <Crystalline Size> As described above, particles (microparticles) that fall off from components exposed to plasma may adhere to the semiconductor substrate and become foreign matter that causes circuit defects. At this time, the smaller the particle size, the more it can suppress the generation of defects. Therefore, the crystallite size of the protective film is preferably less than 40 nm, more preferably less than 30 nm, further preferably less than 20 nm, further preferably less than 15 nm, particularly preferably less than 11 nm, especially preferably less than 10 nm, very preferably less than 9 nm, and most preferably less than 8 nm. On the other hand, the crystallite size of the protective film is preferably greater than 2 nm, more preferably greater than 6 nm, and further preferably greater than 7 nm.

[0027] In order to make the crystallite size within the above range, it is preferred to produce the protective film by the method described later (this production method).

[0028] The crystallite size of the protective film was determined using the Scherrer formula based on the XRD pattern data obtained by XRD measurement of the mirror-polished protective film.

[0029] <Thickness> The thickness of the protective film is, for example, 0.3 μm or more, preferably 1.0 μm or more, more preferably 1.5 μm or more, further preferably 5 μm or more, particularly preferably 10 μm or more, and most preferably 15 μm or more. On the other hand, the thickness of the protective film is, for example, 300 μm or less, preferably 200 μm or less, more preferably 100 μm or less, further preferably 50 μm or less, and particularly preferably 30 μm or less. The thickness of the protective film may also be 10 μm or less.

[0030] The thickness of the protective film was measured as follows. The cross section of the protective film was observed using a scanning electron microscope (SEM), and the thickness of the protective film was measured at five random points. The average value of the five measured points was regarded as the thickness of the protective film (unit: μm).

[0031] <Number of hydrogen atoms> The number of hydrogen atoms in the protective film is preferably small, thereby making the protective film more resistant to plasma. The reason for this is presumably as follows. If the protective film contains a high amount of hydrogen, it is more likely to react with fluorine contained in the plasma (or the gas used to generate the plasma), resulting in increased damage to the protective film. On the other hand, if the protective film contains a low amount of hydrogen, the reaction with fluorine is relatively reduced, thus suppressing damage to the protective film.

[0032] Specifically, the number of hydrogen atoms in the protective film (the number of hydrogen atoms in the film) is preferably 5.0×10 21 atoms / cm 3 or less, more preferably 4.5×10 21 atoms / cm 3 or less, further preferably 3.5×10 21 atoms / cm 3 or less, further preferably 3.0×10 21 atoms / cm 3 or less, particularly preferably 2.5×10 21 atoms / cm 3 or less, and most preferably 2.3×10 21 atoms / cm 3 or less.

[0033] Furthermore, the hydrogen in the protective film is most likely generated by the moisture contained in the substrate described later. In particular, when the substrate is made of ceramic, the number of hydrogen atoms in the formed protective film can be reduced by heating the substrate (preheating) before forming the protective film. In addition, the method of reducing the number of hydrogen atoms in the protective film will be described below.

[0034] On the other hand, the number of hydrogen atoms in the protective film is preferably 0.1×10 21 atoms / cm 3 or more, more preferably 0.5×10 21 atoms / cm 3 or more.

[0035] The number of hydrogen atoms in the protective film was determined using a secondary ion mass spectrometer (IMS-6f, manufactured by AMETEK) with a primary ion species of Cs +, a primary acceleration voltage of 15.0 kV, a detection area of ​​ϕ8 μm, and a measurement depth of 500 nm.

[0036] <Compressive stress> The stress of the protective film (internal stress, residual stress) is not tensile stress, but preferably compressive stress. The compressive stress of the protective film is preferably 100 MPa or more, more preferably 200 MPa or more, and even more preferably 300 MPa or more. On the other hand, the compressive stress of the protective film is preferably 1700 MPa or less, more preferably 1600 MPa or less, and further preferably 1500 MPa or less.

[0037] The compressive stress of the protective film is obtained as follows. A protective film was formed on a quartz glass substrate. The surface shape of the formed protective film was measured using a surface profile measurement device (Surfcom NEX 241 SD2-13, manufactured by Tokyo Seimitsu Co., Ltd.). The compressive stress (film stress σ) of the protective film was calculated using the Stoney equation (the following formula). The Stoney formula is expressed as follows. σ=Yd 2 / 6(1- ν)t×8h / c 2+4h2 In the above formula, σ is the film stress, Y is the Young's modulus of the substrate, d is the thickness of the substrate, ν is the Poisson's ratio of the substrate, t is the thickness of the protective film, h is the warpage, and c is the radius of curvature.

[0038] [member] FIG. 1 is a schematic diagram showing an example of a component 6 . The member 6 includes a substrate 5 and an yttrium protective film 4 . As shown in FIG1 , base layers (base layer 1 , base layer 2 , and base layer 3 ) may be disposed between the substrate 5 and the yttrium protective film 4 . However, the number of base layers is not limited to three.

[0039] The component of this embodiment (hereinafter also referred to as "this component") has the above-mentioned this protective film as the yttrium protective film. Since the surface of this component is covered with this protective film, it has excellent plasma resistance similar to that of the protective film.

[0040] The following describes in detail the various parts of this component.

[0041] <Base Material> The substrate has at least a surface on which the yttrium protective film (or underlying layer, described below) is formed. Hereinafter, for convenience, this surface may be referred to as the "film-forming surface."

[0042] Materials The material of the base material can be appropriately selected according to the purpose of the component. The substrate contains, for example, at least one selected from the group consisting of carbon (C), ceramics, and metals. Here, the ceramic is, for example, at least one selected from the group consisting of glass (soda-lime glass, etc.), quartz, alumina (Al2O3), 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 can be obtained by heating and melting Si element and then 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).

[0043] "shape" The shape of the substrate is not particularly limited, and may be, for example, a flat plate, a ring, a dome, a concave shape, or a convex shape, and may be appropriately selected depending on the intended use of the component.

[0044] Surface roughness of film-forming surface Regarding the surface roughness of the film-forming surface of the substrate, for the reasons described below, the arithmetic mean roughness Ra is preferably less than 1.0 μm, more preferably 0.6 μm or less, further preferably 0.3 μm or less, further preferably 0.1 μm or less, particularly preferably 0.08 μm or less, even more preferably 0.05 μm or less, very preferably 0.01 μm or less, and most preferably 0.005 μm or less. On the other hand, the surface roughness of the film-forming surface of the substrate is preferably 0.01 μm or more, more preferably 0.05 μm or more, and further preferably 0.1 μm or more in terms of arithmetic mean roughness Ra. The surface roughness (arithmetic mean roughness Ra) of the film-forming surface was measured in accordance with JIS B 0601:2001.

[0045] Maximum length of film-forming surface The maximum length of the film-forming surface of the substrate is preferably 30 mm or more, more preferably 100 mm or more, further preferably 200 mm or more, further preferably 300 mm or more, particularly preferably 500 mm or more, very preferably 800 mm or more, and most preferably 1000 mm or more. Furthermore, "maximum length" refers to the maximum length of the film-forming surface. Specifically, for example, if the film-forming surface is circular when viewed from above, it refers to its diameter; if it is ring-shaped when viewed from above, it refers to its outer diameter; if it is a quadrilateral when viewed from above, it refers to the length of the maximum diagonal. On the other hand, the maximum length of the film-forming surface is, for example, less than 2000 mm, preferably less than 1500 mm.

[0046] FIG2 is a schematic diagram showing a half of the ring-shaped substrate 5 cut away. Regarding the substrate 5 shown in FIG. 2 , for example, when the outer diameter D 1 is 100 mm, the inner diameter D 2 is 90 mm, and the thickness t is 5 mm, the maximum length is 100 mm. The substrate 5 has a film forming surface 7, but as shown in FIG. 2 , it may have a first film forming surface 7a that defines the maximum length (outer diameter D1) and a second film forming surface 7b that is different from the first film forming surface 7a. The ratio of the area of ​​the second film-forming surface 7 b to the total area of ​​the film-forming surface 7 is, for example, 60% or less.

[0047] FIG3 is a schematic diagram showing a portion of the cross section of another annular substrate 5 . As shown in FIG3 , the substrate 5 may also have a plurality of second film-forming surfaces 7 b.

[0048] FIG4 is a schematic diagram showing a portion of the cross section of another annular substrate 5 . The angle between the first film forming surface 7a and the second film forming surface 7b is, for example, 20° to 120°. In the substrate 5 shown in FIG4 , the angle between the first film forming surface 7a and the second film forming surface 7b connected to the first film forming surface 7a is approximately 30°.

[0049] <Basal layer> As mentioned above, one or more base layers may be disposed between the substrate and the yttrium protective film. By forming the base layer, the tensile stress of the yttrium protective film is relaxed and compressive stress is generated, or the adhesion of the yttrium protective film to the substrate is increased.

[0050] There is no particular upper limit on the number of base layers, but it is preferably 5 layers or less, more preferably 4 layers or less, further preferably 3 layers or less, particularly preferably 2 layers or less, and most preferably 1 layer.

[0051] The base layer is preferably an amorphous film or a microcrystalline film.

[0052] The base layer preferably contains at least one oxide selected from the group consisting of Al2O3, SiO2, Y2O3, MgO, ZrO2, La2O3, Nd2O3, Yb2O3, Eu2O3 and Gd2O3.

[0053] When two or more base layers are disposed between the substrate and the yttrium protective film, the oxide of the base layers is preferably different between adjacent base layers. The so-called oxides in adjacent base layers are different from each other. Specifically, for example, the oxide of base layer 1 is "SiO 2", the oxide of base layer 2 is "Al 2O 3+SiO 2", and the oxide of base layer 3 is "Al 2O 3".

[0054] The thickness of the base layer is preferably 0.1 μm or more, more preferably 0.4 μm or more, and further preferably 0.8 μm or more. On the other hand, the thickness of the base layer is, for example, 15 μm or less, preferably 10 μm or less, more preferably 7 μm or less, and further preferably 3 μm or less. The thickness of the base layer was measured in the same manner as the thickness of the yttrium protective film.

[0055] <Purpose of components> This component is used as a top plate or other component inside a semiconductor device manufacturing device (plasma etching device, plasma CVD device, etc.). However, the use of this component is not limited to this.

[0056] [Method for manufacturing yttrium protective film and component] Next, a method for manufacturing the yttrium protective film of this embodiment (hereinafter also referred to as "this manufacturing method") will be described. This manufacturing method is also a method for manufacturing the above-mentioned component.

[0057] This manufacturing method is the so-called ion-assisted deposition (IAD, Ion Assisted Deposition) method. In brief, in a vacuum, while irradiating ions, the evaporation source (Y2O3) evaporates and adheres to the substrate, thereby forming an yttrium protective film containing Y2O3.

[0058] This manufacturing method allows for the formation of a very dense yttrium protective film. Specifically, the resulting yttrium protective film has a low porosity and a small crystallite size.

[0059] However, the thicker the yttrium protective film becomes, the more likely it is to crack. Furthermore, by increasing the area of ​​the film-forming surface, the area of ​​the yttrium protective film formed on the film-forming surface is also increased. In this case, cracks are also easily generated on the yttrium protective film.

[0060] However, by this manufacturing method, a dense and relatively hard yttrium protective film can be obtained. Furthermore, when forming the base layer, the tensile stress of the yttrium protective film is relaxed. Therefore, the yttrium protective film obtained by this manufacturing method is not prone to cracking even if the thickness or area is increased.

[0061] Furthermore, the surface roughness (arithmetic mean roughness Ra) of the film-forming surface of the substrate is preferably within the above range. This makes the formed yttrium protective film denser and harder, and less likely to crack.

[0062] Furthermore, if methods such as spraying, aerosol deposition (AD), and ion plating (IP) are used, the resulting yttrium protective film is likely to have many remaining pores.

[0063] <Device Configuration> Based on FIG5, this manufacturing method is demonstrated in more detail. FIG5 is a schematic diagram showing an apparatus used in manufacturing the yttrium protective film. The apparatus shown in Fig. 5 has a chamber 11. The interior of the chamber 11 can be evacuated to a vacuum state by driving a vacuum pump (not shown). Crucibles 12 and 13 and an ion gun 14 are disposed inside the chamber 11, and a support 17 is disposed above them. The bracket 17 is formed integrally with the support shaft 16 and rotates along with the rotation of the support shaft 16. A heater 15 is arranged around the bracket 17. The substrate 5 is held on the support 17 with its film-forming surface facing downward. The substrate 5 held on the support 17 is heated by the heater 15 while rotating as the support 17 rotates. Furthermore, a quartz crystal type film thickness monitor 18 and a quartz crystal type film thickness monitor 19 are installed in the chamber 11 .

[0064] <Formation of Yttrium Protective Film> The following describes the process of forming a yttrium protective film (not shown in FIG5 ) on the substrate 5 in the apparatus shown in FIG5 . First, one or both of the crucible 12 and the crucible 13 are filled with the evaporation source Y 2 O 3 . After the substrate 5 is held on the holder 17 , the interior of the chamber 11 is evacuated to a vacuum state. Then, the holder 17 is rotated while the heater 15 is driven. Thus, the substrate 5 is heated and rotated. In this state, ion-assisted vapor deposition is performed to form a film on the substrate 5 . That is, while ions (ion beam) are irradiated from the ion gun 14, the evaporation source Y 2 O 3 filled in one or both of the crucibles 12 and 13 is evaporated. The ions irradiated by the ion gun 14 are preferably ions of at least one element selected from the group consisting of oxygen, argon, neon, krypton, and xenon. The evaporation source is melted and evaporated by irradiating an electron beam (not shown). In this way, the evaporation source is attached to the substrate 5 (the film-forming surface) to form an yttrium protective film.

[0065] Pressure in the chamber The film formation is performed in a vacuum. Specifically, the internal pressure of the chamber 11 is preferably 6×10 −2 Pa or less, more preferably 5×10 −2 Pa or less, and further preferably 3×10 −2 Pa or less. On the other hand, the internal pressure of the chamber 11 is preferably higher than 1×10 −6 Pa, more preferably higher than 1×10 −5 Pa, and more preferably higher than 1×10 −4 Pa.

[0066] Temperature of the substrate During film formation, the temperature of the substrate 5 heated by the heater 15 is preferably 200° C. or higher, more preferably 250° C. or higher. On the other hand, the temperature is preferably 400°C or lower, more preferably 350°C or lower.

[0067] Film Forming Speed The speed (film formation speed) at which the evaporation sources in the crucibles 12 and 13 are evaporated to form a film is monitored in advance using the quartz crystal film thickness monitor 18 and the quartz crystal film thickness monitor 19 , respectively. The film formation rate is adjusted by controlling the conditions of the electron beam irradiating the evaporation source or the conditions of the ion beam of the ion gun 14 (current value, current density, etc.). During the formation of the yttrium protective film, the film formation rate (unit: nm / min) of each evaporation source is adjusted to the desired value.

[0068] The film formation rate of the evaporation source Y2O3 is preferably 1 nm / min or more, more preferably 1.5 nm / min or more, and further preferably 2 nm / min or more. The film formation rate of the evaporation source Y2O3 is preferably less than 20 nm / min, more preferably less than 15 nm / min, and further preferably less than 10 nm / min.

[0069] Conditions for ion irradiation The distance between the ion gun 14 and the substrate 5 is preferably 700 mm or more, more preferably 900 mm or more. On the other hand, the distance is preferably 1500 mm or less, more preferably 1300 mm or less. The current value of the ion beam is preferably 1000 mA or more, more preferably 1500 mA or more. On the other hand, the current value of the ion beam is preferably 3000 mA or less, more preferably 2500 mA or less.

[0070] Regarding the ion beam current density, in order to make the obtained yttrium protective film harder, it is preferably 40 μA / cm 2 or more, more preferably 65 μA / cm 2 or more, further preferably 75 μA / cm 2 or more, and particularly preferably 77 μA / cm 2 or more. On the other hand, the ion beam current density is preferably 140 μA / cm 2 or less, more preferably 120 μA / cm 2 or less, and further preferably 100 μA / cm 2 or less.

[0071] <Formation of the basal layer> Before forming the yttrium protective film, it is preferred to form the above-mentioned base layers (eg, base layer 1, base layer 2, and base layer 3) on the film formation surface of the substrate 5. The base layer is formed by ion-assisted vapor deposition in the same manner as the yttrium protective film. For example, when forming a base layer containing Al2O3, Al2O3 is filled into one or both of the crucibles 12 and 13 as an evaporation source, and while ions (ion beam) are irradiated from the ion gun 14, the evaporation source is evaporated and attached to the film formation surface of the substrate 5. The conditions for forming the base layer are based on the conditions for forming the yttrium protective film.

[0072] However, the substrate may contain water of crystallization. For example, when the temperature of an aluminum oxide (Al2O3) substrate is raised from room temperature, the generation of crystal water from a hydrate of a low-temperature stable phase of aluminum oxide (e.g., boehmite gamma-alumina) can be observed at around 520°C. If the formed yttrium protective film contains moisture generated by the crystal water of the substrate, the number of hydrogen atoms in the yttrium protective film will increase.

[0073] Therefore, before the evaporation source Y 2 O 3 is attached to the film-forming surface of the substrate (ie, before forming the yttrium protective film), a base layer is formed on the film-forming surface of the substrate. In this way, at least the film-forming surface of the substrate is covered, so the formed yttrium protective film is less likely to contain the crystallization water of the substrate, thereby reducing the number of hydrogen atoms in the yttrium protective film, which is better.

[0074] <Preheating of substrate> Similar to the formation of the base layer, for the reason that the yttrium protective film is less likely to contain the crystal water of the substrate, it is preferable to heat the substrate at a high temperature (preheating) before allowing the evaporation source Y2O3 to adhere to the film-forming surface of the substrate (i.e., forming the yttrium protective film). The preheating temperature is preferably 300° C. or higher, more preferably 400° C. or higher, further preferably 450° C. or higher, and particularly preferably 500° C. or higher. On the other hand, the preheating temperature is, for example, 800° C. or lower, preferably 750° C. or lower, and more preferably 700° C. or lower.

[0075] The preheating time is preferably 60 minutes or longer, more preferably 120 minutes or longer, further preferably 240 minutes or longer, and particularly preferably 480 minutes or longer. On the other hand, the preheating time is preferably 1200 minutes or less, more preferably 1000 minutes or less, further preferably 800 minutes or less, and particularly preferably 600° C. or less.

[0076] The preheating atmosphere is, for example, air. Example

[0077] The present invention will be described in detail below with reference to the following examples. However, the present invention is not limited to the following examples. Hereinafter, Examples 1 to 27, 30 to 31, and 39 to 42 are embodiments, Examples 28 to 29, 32 to 33, and 37 to 38 are comparative examples, and Examples 34 to 36 are reference examples.

[0078] <Example 1> Using the apparatus described based on FIG. 5 , a yttrium protective film (protective film) was produced under the conditions shown in Table 1 below.

[0079] As the substrate, a circular substrate (thickness: 10 mm) containing aluminum oxide (Al 2 O 3 ) and having a film-forming surface with a diameter (maximum length) of the value shown in Table 1 below was used. The substrate was preheated in an ambient atmosphere while held on a holder within the chamber. The preheating temperature was set to the temperature shown in Table 1 below (unit: °C) and the preheating time was set to 600 minutes. If the substrate was not preheated, "-" is entered in the preheating temperature column.

[0080] Then, under the manufacturing conditions shown in Table 1 below, a base layer and a yttrium protective film (protective film) shown in Table 1 below were formed on the film formation surface of the substrate. As manufacturing conditions not described in Table 1 below, oxygen (O) ions were irradiated from an ion gun, the distance between the ion gun and the substrate was set to 1100 mm, and the current value of the ion beam was set to 2000 mA.

[0081] FIG6 is an XRD pattern of the yttrium protective film of Example 1. As shown in FIG. 6 , it can be seen that in the yttrium protective film of Example 1, the (222) plane, which is the closest-packed plane of the cubic crystal structure, is preferentially oriented at around 28°.

[0082] The yttrium protective film of Example 1 was observed using a SEM at a magnification of 50,000 times. Figure 7 is a surface SEM photograph of the yttrium protective film of Example 1. Figure 8 is a cross-sectional SEM photograph of the yttrium protective film of Example 1. As shown in Figures 7 and 8, it can be seen that the yttrium protective film of Example 1 is very dense and has excellent smoothness. It can also be seen that the particle size is uniform.

[0083] <Example 2~Example 33> In Examples 2 to 33, one or more conditions were changed from those in Example 1. Otherwise, the same operation as in Example 1 was performed to produce a yttrium protective film (protective film). In summary, for example, it is as follows. In addition, in each example, in addition to the following description, there are also cases where changes are made from Example 1.

[0084] In Example 2, the ion beam current density was changed from Example 1. In Examples 3 to 6, the number of layers and / or composition of the base layer were changed from Example 1. In Examples 7 to 10, no base layer was formed.

[0085] In Examples 11 to 20, the substrate and / or base layer were modified from Example 1. Furthermore, in Example 13, commercially available soda-lime glass was used as the substrate (glass). In Example 15, one side of a substrate containing an aluminum single crystal was subjected to an alumite treatment and then polished to form an underlayer containing Al 2 O 3. In Table 1 below, this underlayer is described as "anlumite layer." In Example 16, one side of an aluminum substrate was anodized using oxalic acid to form an underlayer containing Al 2 O 3. In Table 1 below, this underlayer is described as "anodized layer."

[0086] In Examples 21 and 22, the thickness of the protective film was changed from that in Example 1. In Examples 23 and 24, the area of ​​the film-forming surface was changed from Example 1. In Examples 25 to 29, the chamber pressure was changed from that in Example 1. Furthermore, the protective film in Example 28 was amorphous (hence, "-" was recorded in the "Orientation" column). In Examples 30 and 31, the film forming speed was changed from Example 1. In Examples 32 and 33, the surface roughness (Ra) of the film-forming surface was changed from Example 1.

[0087] <Example 34~Example 36> In Example 34, sapphire is made into a protective film. In Example 35, metallic aluminum is made into a protective film. In Example 36, quartz is formed into a protective film.

[0088] <Example 37~Example 38> In Example 37, the IP method was used instead of the IAD method to form the Y 2 O 3 protective film. In Example 38, the Y 2 O 3 protective film was formed using the CVD method instead of the IAD method.

[0089] <Example 39~Example 42> In Examples 39 to 42, except that the substrate was not preheated, the same operations as in Examples 7, 1, 3, and 26 were performed to form the protective film.

[0090] <Properties of protective film> The number of hydrogen atoms, Vickers hardness, porosity, crystallite size, orientation, thickness, and compressive stress of the protective film of each example were determined using the above-described method. The results are shown in Table 1 below. Furthermore, regarding compressive stress, the numerical value is recorded as a negative value.

[0091] <Etching Amount> The protective film of each example was subjected to ion etching and / or radical etching to evaluate plasma resistance.

[0092] Specifically, first, a 10 mm × 5 mm surface of the protective film was mirror-finished, and Kapton tape was affixed to a portion of the mirror-finished surface (called the "test surface") for masking. Next, a CCP (Capacitively Coupled Plasma) plasma etching apparatus was used to discharge in the gas described later at a pressure of 10 Pa and a radio frequency (RF) power of 600 W to generate plasma. A test was then conducted in which the test surface was exposed to the generated plasma (exposure test).

[0093] In ion etching, discharge (plasma generation) is performed using carbon tetrafluoride gas (flow rate: 100 sccm) and oxygen gas (flow rate: 100 sccm), thereby generating carbon tetrafluoride ions in the plasma. In the radical etching, discharge (plasma generation) is performed using carbon tetrafluoride gas (flow rate: 100 sccm), argon gas (flow rate: 50 sccm), and oxygen gas (flow rate: 100 sccm), thereby generating fluorine radicals in the plasma.

[0094] Repeat the 15-minute discharge (plasma generation) five times for a total of 150 minutes of exposure. In this way, the unshielded portion of the test surface was etched. The etching amount was then determined by measuring the difference in level between the shielded and unshielded areas of the test surface using a stylus-type surface profile measuring instrument (Dectak 150, manufactured by ULVAC). The results are shown in Table 1 below. In addition, in the case where ion etching or radical etching was not performed, "-" is recorded in the following Table 1.

[0095] The smaller the etching amount (unit: nm), the better the plasma resistance can be evaluated. Specifically, when the etching amount (ion etching amount, radical etching amount) is 200 nm or less, it can be evaluated that the plasma resistance is excellent.

[0096] <Appearance> Visually inspect the appearance of the formed protective film to confirm whether there are any cracks (including wrinkles, the same applies below). In Table 1 below, cracks of 1.0 mm or larger are marked "present," cracks less than 1.0 mm are marked "slight," and no cracks are marked "absent." Appearance ratings of "slight" or "absent" are considered excellent. Furthermore, in the "mild" case, although fine cracks occurred on the edge of the protective film, no cracks occurred in the center of the protective film.

[0097] [Table 1] Table 1 (Part 1) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Manufacturing conditions Pressure in chamber [Pa] 1×10-2 1×10-2 1×10 - 2 1×10-2 1×10-2 1×10-2 1×10 - 2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 Temperature of substrate [℃] 300 300 300 300 300 300 300 300 300 300 300 300 270 300 Y2O3 Evaporation source film forming speed [nm / min] 3.42 3.42 3.42 3.42 3.42 3.42 3.42 3.42 3.42 3.42 3.42 6.78 3.42 3.42 Ion beam current density [μA / cm 2] 80 70 80 80 80 80 80 80 80 80 80 80 80 80 substrate material Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 quartz quartz Glass Al Preheating temperature [℃] 550 550 550 550 550 550 550 550 550 550 550 550 550 550 Film-forming surface Ra[μm] 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.05 0.22 0.5 0.02 0.02 0.02 0.09 Area [cm 2] 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 Maximum length [mm] 200 200 200 200 200 200 200 200 200 200 200 200 200 200 basal layer 1 composition Al 2O 3 Al 2O 3 SiO 2 SiO 2 SiO 2 SiO 2 - - - - SiO 2 SiO 2 SiO 2 Al 2O 3 Thickness [μm] 1 1 0.5 0.5 0.5 0.5 - - - - 0.5 0.5 0.5 1 2 composition - - Al 2O 3+SiO 2 Al 2O 3+SiO 2 ZrO 2 MgO - - - - Al 2O 3 +SiO 2 Al 2O 3 +SiO 2 Al 2O 3 +SiO 2 - Thickness [μm] - - 1 1 1 1 - - - - 1 1 1 - 3 composition - - - Al 2O 3 Al 2O 3 Al 2O 3 - - - - - - Al 2O 3 - Thickness [μm] - - - 1 1 1 - - - - - - 1 - Protect membrane Number of hydrogen atoms [×10 21 / cm 3] 1.9 2.0 1.9 1.8 2.1 2.1 2.8 2.6 2.8 2.6 1.5 1.7 1.6 2.1 Vickers hardness [HV] 1482 902 1481 1322 1324 1326 1453 1426 1233 852 1412 873 1022 982 Porosity [volume %] 0.04 0.28 0 0.06 0.05 0.07 0.41 0.01 0.19 0.49 0.01 0.23 0 0.16 Crystallite size [nm] 7.9 5.2 8.3 8.2 8.8 8.4 8.3 10.5 11.3 11.2 9.1 9.6 12.2 11.9 Orientation degree[%] 90.8 90.9 91.4 92.1 90.2 90.4 87.4 84.6 66.8 50.9 90.7 88.6 92.2 80.4 Thickness [μm] 15.3 10.6 15.3 15.4 15.4 15.2 13.3 15.2 0.9 12.8 10.5 10.4 15.5 4.4 Compression stress [MPa] -1244 -942 -1246 -1241 -1240 -1233 -1152 -1171 -1127 -1085 -1213 -749 -767 -1043 Ion etching amount [nm] 73 126 73 72 74 75 115 122 186 193 72 87 85 97 Radical etching amount [nm] - - - - - - - - - - - - - - Appearance none none none none none none none none none none none none none none Table 1 (part 2) Example 15 Example 16 Example 17 Example 18 Example 19 Example 20 Example 21 Example 22 Example 23 Example 24 Example 25 Example 26 Example 27 Example 28 Manufacturing conditions Pressure in chamber [Pa] 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-2 1×10-3 1×10-4 1×10-5 1×10-6 Temperature of substrate [℃] 300 300 300 300 300 300 300 300 300 300 300 300 300 300 Y2O3 Evaporation source film forming speed [nm / min] 2.1 3.42 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 1.9 2.1 2.5 4.0 Ion beam current density [μA / cm 2] 80 80 80 80 80 80 80 80 80 80 80 80 78 75 substrate material Al Al AlN AlN AlN Iolite Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Preheating temperature [℃] 550 550 550 550 550 550 550 550 550 550 550 550 550 550 Film-forming surface Ra[μm] 0.03 0.09 0.03 0.05 0.1 0.02 0.02 0.02 0.02 0.02 0.11 0.11 0.19 0.02 Area [cm 2] 314.2 314.2 314.2 314.2 314.2 9503.0 314.2 314.2 17670.9 9503.0 314.2 314.2 314.2 314.2 Maximum length [mm] 200 200 200 200 200 1100 200 200 1500 1100 200 200 200 200 basal layer 1 composition Acid-resistant aluminum film Anodic oxide layer Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 SiO 2 Al 2O 3 - Al 2O 3 - Al 2O 3 Al 2O 3 Thickness [μm] 1 1 1 1 1 1 1 1 1 - 1 - 1 1 2 composition - Al 2O 3 - - - - - Al 2O 3+SiO 2 - - - - - - Thickness [μm] - 1 - - - - - - - - - - - - 3 composition - - - - - - - - - - - - - - Thickness [μm] - - - - - - - - - - - - - - protective film Number of hydrogen atoms [×10 21 / cm 3] 2.1 2.2 2.0 2.0 2.0 0.2 0.8 2.1 2.1 2.6 1.2 2.6 1.5 2.2 Vickers hardness [HV] 1322 1187 1267 1234 1189 1326 1330 1222 1315 1283 1250 1310 1364 420 Porosity [volume %] 0.05 0.33 0.05 0.11 0.18 0.05 0.08 0.07 0.18 0.44 0.06 0.05 0.05 0 Crystallite size [nm] 8.8 13.6 12.3 12.1 12.4 8.8 18.2 7.8 12.1 8.8 8.8 12 14 7.9 Orientation degree[%] 88.2 79.6 84.9 80.1 74.8 84.8 82.7 95.2 88.9 87.9 78.4 77.5 67.3 - Thickness [μm] 15.2 11.1 10.3 10.2 10.3 15.3 204.1 1.4 10.4 10.4 15.2 15.2 15.4 12.4 Compression stress [MPa] -1216 -1173 -1091 -1044 -1032 -1211 -1442 -1034 -1275 -1422 -1275 -1688 -1620 -411 Ion etching amount [nm] 77 83 69 69 73 75 65 70 66 103 71 106 69 234 Radical etching amount [nm] - - 95 97 102 94 97 94 97 121 82 89 86 - Appearance none none none none none none none none none slight none none none have Table 1 (Part 3) Example 29 Example 30 Example 31 Example 32 Example 33 Example 34 Example 35 Example 36 Example 37 Example 38 Example 39 Example 40 Example 41 Example 42 Manufacturing conditions Pressure in chamber [Pa] 7×10 - 2 1×10 - 2 1×10 - 3 1×10 - 4 1×10 - 5 - - - - - 1×10 - 2 1×10 - 2 1×10 - 2 1×10-4 Temperature of substrate [℃] 300 300 300 300 300 - - - - - 300 300 300 300 Y2O3 Evaporation source film forming speed [nm / min] 2.1 3.6 1.9 2.1 2.1 - - - - - 3.42 3.42 3.42 2.1 Ion beam current density [μA / cm 2] 70 80 80 85 80 - - - - - 80 80 80 80 substrate material Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 - - - Al 2O 3 quartz Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Preheating temperature [℃] 550 550 550 550 550 - - - 550 550 - - - - Film-forming surface Ra[μm] 0.02 0.11 0.11 1.0 1.5 - 0.091 - 0.02 0.02 0.02 0.02 0.02 0.11 Area [cm 2] 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 314.2 Maximum length [mm] 200 200 200 200 200 200 200 200 200 200 200 200 200 200 basal layer 1 composition Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 Al 2O 3 - - - - - - Al 2O 3 SiO 2 - Thickness [μm] 1 1 1 1 1 - - - - - - 1 0.5 - 2 composition - - - - - - - - - - - - Al 2O 3 +SiO 2 - Thickness [μm] - - - - - - - - - - - - 1 - 3 composition - - - - - - - - - - - - - - Thickness [μm] - - - - - - - - - - - - - - protective film Number of hydrogen atoms [×10 21 / cm 3] 3.0 2.4 1.9 2.2 2.1 - - - 5.2 6.7 4.4 3.2 3.1 3.9 Vickers hardness [HV] 685 1145 1288 494 494 - - - 780 560 1410 1432 1429 1298 Porosity [volume %] 1.2 0.05 0.05 1.57 1.57 0 0 0 0.21 0.87 0.38 0.09 0.08 0.09 Crystallite size [nm] 10 8.8 8.8 11.2 11.8 - - - 7.1 7.9 8.5 7.8 8.4 11.6 Orientation degree[%] 67.2 75.6 77.3 33.1 23.8 - - - 48.3 55.2 86.9 90.4 91.2 77.6 Thickness [μm] 18.5 14.3 14.6 12.2 12.2 - - - 9.4 7.1 13.3 15.3 15.3 15.2 Compressive stress [MPa] -587 -412 -1591 -1547 -1682 - - - -1560 -569 -1139 -1239 -1244 -1567 Ion etching amount [nm] 224 99 97 135 168 781 845 1620 247 256 174 139 131 178 Radical etching amount [nm] - - - - - - - - - - - - - 109 Appearance none none slight have have - - - none have none none none none

[0098] <Summary of evaluation results> As shown in Table 1, the yttrium protective films of Examples 1 to 27 and Examples 30 and 31 exhibited excellent plasma resistance and appearance. In contrast, the yttrium protective films of Examples 28 and 29, Examples 32 and 33, and Examples 37 and 38 exhibited insufficient plasma resistance or appearance.

[0099] Several examples are explained below. Example 2: By reducing the ion beam current density, the compressive stress of the protective film is reduced. Examples 8 to 10: As the surface roughness of the film-forming surface increases, the compressive stress of the protective film decreases. Example 12: As the film formation speed is increased, the effect of ion irradiation becomes smaller, which reduces the compressive stress of the protective film. Example 13: This is an example of using soda-lime glass as the substrate. By lowering the temperature of the substrate, the compressive stress of the protective film is reduced. Examples 26 and 27: Since the pressure in the chamber during film formation is reduced, the mean free path becomes longer, which increases the kinetic energy generated by the collision between the irradiated ions and the particles (evaporation source), thereby increasing the compressive stress of the protective film. Example 28: As the film formation speed is increased, the effect of ion irradiation becomes smaller, which reduces the compressive stress of the protective film. Example 29: By reducing the ion beam current density, the compressive stress of the protective film is reduced. Example 30: Since the temperature of the evaporation source is lowered, the crystal growth slows down, reducing the compressive stress of the protective film. Example 31: Since the pressure in the chamber during film formation is reduced, and thus the film formation speed is reduced, the effect of ion irradiation is increased, thereby increasing the compressive stress of the protective film. Case 32~Case 33: Since the pressure in the chamber during film formation is reduced, the mean free path becomes longer, which increases the kinetic energy generated by the collision between the irradiated ions and the particles (evaporation source), thereby increasing the compressive stress of the protective film. In Examples 39 to 42, since the substrate was not preheated, the number of hydrogen atoms in the protective film increased compared to Examples 7, 1, 3, and 26 in which the substrate was preheated. Furthermore, all contents of the specifications, claim scopes, drawings and abstracts of Japanese Patent Application No. 2022-131021 filed on August 19, 2022 and Japanese Patent Application No. 2022-175428 filed on November 1, 2022 are cited herein and introduced as a disclosure of the present invention.

[0100] 1: basal layer 2: Basal layer 3: Basal layer 4: Yttrium protective film 5: Base material 6: Component 7: Film-forming surface 7a: First film-forming surface 7b: Second film-forming surface 11: Chamber 12: Crucible 13: Crucible 14: Ion Gun 15: Heater 16: Support shaft 17: Bracket 18: Quartz crystal film thickness monitor 19: Quartz crystal film thickness monitor D 1: Outer diameter D 2:Inner diameter t: thickness

Claims

1. A yttrium protective film containing yttrium oxide, having a porosity of less than 0.5% by volume, a Vickers hardness of 800 HV or higher, and an orientation degree of 50% or higher for the (222) facet of Y2O3.

2. The yttrium protective film, as requested in item 1, has a thickness of 0.3 μm or more.

3. The yttrium protective film, as requested in item 1, has a thickness of less than 15 μm.

4. The yttrium protective film of claim 1 has a crystallite size of less than 40 nm.

5. The yttrium protective film of request item 1 has a crystallite size of 6 nm or more.

6. The yttrium protective film as requested in item 1, wherein the number of hydrogen atoms is less than 5.0 × 10²¹ / cm³.

7. The yttrium protective film of claim 1 has a compressive stress of 100 to 1700 MPa.

8. A component having: a substrate, and a yttrium protective film as claimed in any one of claims 1 to 7, wherein the yttrium protective film is disposed on the surface of the substrate to form a film surface.

9. The component of claim 8, wherein the substrate comprises at least one selected from the group consisting of carbon, ceramics and metals, wherein the ceramic is selected from the group consisting of glass, quartz, alumina, aluminum nitride, cordierite, yttrium oxide, silicon carbide, Si impregnated with silicon carbide, silicon nitride, siliconium oxynitride, and aluminum oxynitride, and wherein the metal is selected from the group consisting of aluminum and aluminum-containing alloys.

10. The component of claim 8, wherein the substrate contains alumina.

11. The component of claim 8, wherein the substrate contains quartz.

12. The component of claim 8, wherein the surface roughness of the film-forming surface is less than 1.0 μm when measured by arithmetic mean roughness Ra.

13. The component of claim 8, wherein the surface roughness of the film-forming surface is 0.01 μm or more, calculated as an arithmetic mean roughness Ra.

14. The component of claim 8, wherein the maximum length of the aforementioned film-forming surface is 30 mm or more.

15. The component of claim 8, wherein a base layer is provided between the substrate and the yttrium protective film, the base layer containing at least one oxide selected from the group consisting of Al2O3, SiO2, Y2O3, MgO, ZrO2, La2O3, Nd2O3, Yb2O3, Eu2O3 and Gd2O3.

16. The component of claim 15, wherein there are two or more base layers between the substrate and the yttrium protective film, and the oxides are different from each other in adjacent base layers.

17. The component of claim 8, wherein the substrate has a first film-forming surface with a specified maximum length and a second film-forming surface different from the first film-forming surface as the film-forming surface, the angle between the first film-forming surface and the second film-forming surface is 20° to 120°, and the ratio of the area of ​​the second film-forming surface to the total area of ​​the film-forming surfaces is 60% or less.

18. The component of claim 8 is used inside a plasma etching apparatus or a plasma CVD apparatus.

19. A method for manufacturing a yttrium protective film, comprising the method of manufacturing a yttrium protective film as claimed in any one of claims 1 to 7, wherein, in a vacuum, ions of at least one element selected from the group consisting of oxygen, argon, neon, krypton and xenon are irradiated, and an evaporation source is evaporated and attached to a substrate, wherein Y2O3 is used as the evaporation source.

20. A method for manufacturing a yttrium protective film as claimed in claim 19, wherein the substrate is heated at a temperature of 300°C or higher before the evaporation source is attached to the substrate.

21. A method for manufacturing a yttrium protective film as claimed in claim 19, wherein before attaching the evaporation source to the substrate, one or more base layers are formed on the surface of the substrate, the base layer containing at least one oxide selected from the group consisting of Al2O3, SiO2, Y2O3, MgO, ZrO2, La2O3, Nd2O3, Yb2O3, Eu2O3 and Gd2O3.

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