Yttrium-based protective film, member, and method for producing same

Abstract

In this yttrium-based protective film, the fracture toughness value is 0.60 MPa·m1 / 2 or greater, the thickness is 10.0 μm or less, the porosity is preferably less than 0.50 vol%, the crystallite size is preferably 6.0-40.0 nm, the average linear expansion coefficient at 50-500°C is preferably 7.0-10.0 ppm / K, the number of hydrogen atoms is preferably 5.0 × 1021 atoms per cm3 or less, the compressive stress is preferably 100-1700 MPa, and the heat-resistant temperature is preferably 500°C or higher.

Description

Yttrium-based protective film, component and method for producing same

[0001] The present invention relates to an yttrium-based protective film, a member, and a method for producing the same.

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

[0003] At this time, components exposed to the plasma in the chamber may corrode, and the corroded parts may fall off in the form of particles. The fallen particles may adhere to the semiconductor substrate and become foreign matter that causes defects in the circuit.

[0004] Therefore, a protective film containing yttrium oxide or yttrium oxyfluoride (yttrium-based protective film) has been known as a protective film for protecting a member exposed to plasma. Patent Document 1 discloses a thermal spray coating containing yttrium oxide or yttrium oxyfluoride formed by thermal spraying.

[0005] Japanese Patent Application Publication No. 2018-76546

[0006] The inventors have found through their investigations that conventional yttrium-based protective films are sometimes insufficient in terms of thermal cycle resistance and plasma resistance (corrosion resistance to plasma).

[0007] The present invention has been made in view of the above points, and has as its object to provide an yttrium-based protective film that is excellent in thermal cycle resistance and plasma resistance.

[0008] As a result of extensive research, the present inventors have found that the above object can be achieved by adopting the following configuration, and have completed the present invention. That is, the present invention provides the following [1] to

[19] . [1] A fracture toughness value of 0.60 MPa m １／２[2] The yttrium protective film according to the above [1], which has a porosity of less than 0.50% by volume. [3] The yttrium protective film according to the above [1] or [2], which has a crystallite size of 6.0 nm or more and 40.0 nm or less. [4] The yttrium protective film according to any one of the above [1] to [3], which has an average linear expansion coefficient at 50 to 500°C of 7.0 ppm / K or more and 10.0 ppm / K or less. [5] The number of hydrogen atoms is 5.0 x 10 ２１ pieces / cm ３ [6] The yttrium-based protective film according to any one of the above [1] to [4], which has a compressive stress of 100 to 1700 MPa. [7] The yttrium-based protective film according to any one of the above [1] to [6], which has a heat-resistant temperature of 500°C or higher. [8] Y ２ O ３ [9] The yttrium-based protective film according to any one of the above [1] to [7], containing ２ O ３

[10] The yttrium-based protective film according to the above [8], wherein the orientation degree of the (222) plane is 50.0% or more. ５ O ４ F ７ The yttrium-based protective film according to any one of the above [1] to [7], wherein the peak intensity ratio of the yttrium-based protective film according to any one of the above [1] to

[10] is 60% or more.

[11] A member comprising a substrate and the yttrium-based protective film according to any one of the above [1] to

[10] , in this order.

[12] The member according to the above

[11] , wherein the substrate is made of at least one material selected from the group consisting of carbon, ceramics, and metals.

[13] The member according to the above

[12] , wherein the ceramic is at least one material selected from the group consisting of glass, quartz, and cordierite.

[14] The member according to any one of the above

[11] to

[13] , wherein one or more underlayers are provided between the substrate and the yttrium-based protective film.

[15] The underlayer is made of Al ２ O ３ , SiO ２ , Y ２ O ３, MgO, CaO, SrO, BaO, B ２ O ３ , SnO ２ , P ２ O ５ , Li ２ O, Na ２ O.K. ２ O, ZrO ２ , La ２ O ３ , Nd ２ O ３ , Yb ２ O ３ , Eu ２ O ３ , Gd ２ O ３ , Ta ２ O ３ , Nb ２ O ５ , HfO ２ , CeO ２ , W.O. ３ , TiO ２

[16] The member according to any one of

[11] to

[15] above, which is used inside a plasma processing apparatus.

[17] A method for producing the member according to any one of

[11] to

[16] above, comprising evaporating an evaporation source while irradiating the substrate with ions of at least one element selected from the group consisting of oxygen, argon, neon, krypton, and xenon from an ion gun in a vacuum to form the yttrium-based protective film, and ２ O ３ , or Y ２ O ３ and Y.F. ３

[18] The method for manufacturing a member according to the above

[17] , wherein the temperature of the substrate is 200° C. or higher during the formation of the yttrium-based protective film.

[19] The method for manufacturing a member according to the above

[17] or

[18] , wherein one or more underlayers are formed on the surface of the substrate before the formation of the yttrium-based protective film.

[0009] According to the present invention, it is possible to provide an yttrium-based protective film that is excellent in thermal cycle resistance and plasma resistance.

[0010] Fig. 1 is a schematic diagram showing an example of a member. Fig. 2 is a schematic diagram showing a half-cutaway ring-shaped substrate. Fig. 3 is a schematic diagram showing a part of a cross section of another ring-shaped substrate. Fig. 4 is a schematic diagram showing a part of a cross section of yet another ring-shaped substrate. Fig. 5 is a schematic diagram showing an apparatus used to produce an yttrium-based protective film.

[0011] The meanings of terms used in the present invention are as follows: A numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0012] [Yttrium-based protective film] The yttrium-based protective film of this embodiment has a fracture toughness value of 0.60 MPa m １／２ The thickness is 10.0 μm or less. As a result, the yttrium-based protective film of this embodiment has excellent plasma resistance and thermal cycle resistance.

[0013] <Fracture toughness value> The fracture toughness value of the yttrium protective film is 0.60 MPa m １／２ The fracture toughness value of the yttrium protective film is 0.65 MPa m １／２ More than 0.70 MPa m １／２ More preferably, 0.75 MPa m １／２ More preferably, 0.80 MPa m １／２ More preferably, 0.85 MPa m １／２ The above is most preferable.

[0014] The upper limit is not particularly limited, and the fracture toughness value of the yttrium protective film is, for example, 1.20 MPa m １／２ is less than or equal to 1.10 MPa m １／２ It may be 1.00 MPa m or less, １／２ The fracture toughness of the yttrium protective film may be, for example, 0.60 to 1.20 MPa m １／２ and 0.65 to 1.10 MPa m １／２ and 0.70 to 1.00 MPa m １／２and 0.75 to 1.00 MPa m １／２ and 0.80 to 1.00 MPa m １／２ and 0.85 to 1.00 MPa m １／２ may be.

[0015] In the present invention, the fracture toughness (KC) of the yttrium-based protective film is determined using a nanoindenter by the indentation method (IF method) specified in JIS R 1607. First, an indenter is pressed into the yttrium-based protective film under the following condition 1 to determine the Young's modulus and Vickers hardness (ISO 14577 method). Next, under the following condition 2, an indenter is pressed into another portion of the same yttrium-based protective film, and the fracture toughness is determined using the data obtained from this and the previously determined Young's modulus and hardness (IF method). The coefficient of the IF method formula is 0.0319.

[0016] <Condition 1> Nanoindenter: iMicro (KLA Corporation) Actuator: inForce1000 Indenter: Berkovich indenter Measurement mode: Continuous stiffness measurement method (CSM / CSR) Maximum load: 1000 mN Strain rate: 0.2 s －１ ・Maximum load holding time: 10 seconds ・Poisson's ratio of sample: 0.25 ・Number of measurement points: 12 points each

[0017] <Condition 2> Nanoindenter: iMicro (KLA Corporation) Actuator: inForce1000 Indenter: cube corner indenter Measurement mode: continuous stiffness measurement method (CSM / CSR) Maximum indentation depth: 1200 nm Strain rate: 0.2 s －１ ・Maximum load holding time: 10 seconds

[0018] <Thickness> The thickness of the yttrium protective film is 10.0 μm or less. Because the plasma resistance and thermal cycle resistance of the yttrium protective film are superior, the thickness of the yttrium protective film is preferably 8.0 μm or less, more preferably 6.0 μm or less, even more preferably 4.0 μm or less, even more preferably 2.0 μm or less, particularly preferably 0.9 μm or less, and most preferably 0.6 μm or less. The thickness of the yttrium protective film may be 0.5 μm or less. There is no particular lower limit, and the thickness of the yttrium protective film may be, for example, 0.05 μm or more, 0.1 μm or more, or 0.3 μm or more. The thickness of the yttrium protective film may be, for example, 0.05 to 10.0 μm, 0.1 to 8.0 μm, 0.3 to 6.0 μm, 0.3 to 4.0 μm, 0.3 to 2.0 μm, 0.3 to 0.9 μm, or 0.3 to 0.6 μm.

[0019] The thickness of the yttrium-based protective film is measured as follows: a cross section of the yttrium-based protective film is observed using a scanning electron microscope (SEM), the thickness of the yttrium-based protective film is measured at any five points, and the average value of the five measured points is taken as the thickness (unit: μm) of the yttrium-based protective film.

[0020] <Porosity> Because the plasma resistance of the yttrium-based protective film is excellent, the porosity of the yttrium-based protective film is preferably less than 0.50% by volume, more preferably 0.30% by volume or less, even more preferably 0.20% by volume or less, and particularly preferably 0.10% by volume or less.

[0021] In order to set the porosity within the above range, it is preferable to produce the yttrium-based protective film by the production method described below.

[0022] The porosity of the yttrium-based protective film is determined as follows. First, a focused ion beam (FIB) is used to perform a slope process in the thickness direction at an angle of 52° from the surface of the yttrium-based protective film toward the substrate on a portion of the yttrium-based protective film and a substrate described later, thereby exposing a cross section. The exposed cross section is observed at a magnification of 20,000 times using a field emission scanning electron microscope (FE-SEM), and cross-sectional images are taken. Cross-sectional images are taken at multiple locations. Specifically, for example, when the yttrium-based protective film is circular, images are taken at a total of five points, including one point at the center of the surface of the yttrium-based protective film and four points located 10 mm away from the outer periphery, and the size of the cross-sectional images is 6 μm × 5 μm. When the thickness of the yttrium-based protective film is 5 μm or more, cross-sectional images are taken at multiple locations so that the entire cross section of the yttrium-based protective film can be observed in the thickness direction. Subsequently, the obtained cross-sectional image is analyzed using image analysis software (ImageJ, manufactured by the National Institute of Health) to identify the area of ​​the pore portion in the cross-sectional image. The ratio of the area of ​​the pore portion to the area of ​​the entire cross section of the yttrium protective film is calculated, and this is regarded as the porosity (unit: volume%) of the yttrium protective film. Note that for pores that are so fine that they cannot be detected by image analysis software (pores with a pore diameter of 20 nm or less), their area is regarded as 0.

[0023] <Composition> The yttrium-based protective film may contain, for example, either yttrium oxide or yttrium oxyfluoride, or may contain both yttrium oxide and yttrium oxyfluoride.

[0024] <<Yttrium Oxide>> First, the yttrium protective film is made of yttrium oxide (Y ２ O ３ In this case, the Y of the yttrium-based protective film is ２ O ３ The content of Y is preferably 95% by mass or more, more preferably 98% by mass or more, and may be 100% by mass. ２ O ３Yttrium-based protective film produced using only ２ O ３ The content satisfies the above range.

[0025] (Degree of Orientation) When the area of ​​the yttrium-based protective film is increased, the Y of the yttrium-based protective film is increased in order to prevent cracks (including wrinkles; the same applies below) from occurring in the yttrium-based protective film. ２ O ３ The higher the orientation degree of the (222) plane (hereinafter also simply referred to as "orientation degree"), the better. Therefore, the orientation degree of the yttrium-based protective film is, for example, 50.0% or more, preferably 65.0% or more, more preferably 80.0% or more, even more preferably 85.0% or more, even more preferably 90.0% or more, particularly preferably 93.0% or more, more particularly preferably 95.0% or more, very preferably 98.0% or more, and most preferably 99.0% or more. In order to set the orientation degree within the above range, it is preferable to manufacture the yttrium-based protective film by the manufacturing method described below. The orientation degree is determined by measuring the degree of orientation of the Y in the XRD pattern of the yttrium-based protective film. ２ O ３ The peak intensity of the (222) plane is the ratio (unit: %) of the peak intensity of the (222) plane to the total peak intensity of each plane being 100.

[0026] The XRD pattern of the yttrium protective film (and the underlayer described below) is obtained by XRD measurement in a micro-area 2D (two-dimensional) mode using an X-ray diffractometer (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° to 80° Step time: 0.2 s / step Scan speed: 10° / min Step width: 0.02° Detector: Multimode detector EIGER (2D mode) Incident optical system: Multilayer mirror + 1.0 mmφ microslit + 1.0 mmφ collimator Receiving optical system: OPEN

[0027] <<Yttrium oxyfluoride>> Next, a case where the yttrium protective film contains yttrium oxyfluoride will be described. The chemical formula for yttrium oxyfluoride is YOF, Y５ O ４ F ７ YOF is an orthorhombic crystal with low hardness, while Y ５ O ４ F ７ has a special crystal structure called a rhombohedron and has high hardness. In this embodiment, the yttrium protective film is made of Y having a rhombohedron crystal structure. ５ O ４ F ７ It is preferable that the proportion of Y in the X-ray diffraction pattern is high. ５ O ４ F ７ It is preferable that the peak intensity ratio of the yttrium-based protective film is equal to or greater than a certain value. This makes the yttrium-based protective film hard and exhibits a Vickers hardness of equal to or greater than a certain value.

[0028] (Peak intensity ratio) Y in the X-ray diffraction pattern of the yttrium protective film ５ O ４ F ７ The peak intensity ratio (hereinafter referred to as "Y ５ O ４ F ７ The peak intensity ratio (also referred to as "peak intensity ratio" or simply "peak intensity ratio") is preferably 60% or more, more preferably 80% or more, even more preferably 90% or more, and particularly preferably 95% or more.

[0029] Y ５ O ４ F ７ In order to set the peak intensity ratio within the above range, it is preferable to produce an yttrium-based protective film by the production method described below.

[0030] Y ５ O ４ F ７ The peak intensity ratio is the ratio of the Y peak intensity to the Y peak intensity when the sum of the main peak intensities of the following crystalline phases in the X-ray diffraction (XRD) pattern of the yttrium protective film is taken as 100: ５ O ４ F ７ The main peak of each crystalline phase is the ratio of the main peak intensity of Y ５ O ４ F ７ is around 2θ=28.1°, Y ２ O３ appears near 2θ=29.2°, and YOF appears near 2θ=29.2°. ５ O ４ F ７ The main peak position of Y ６ O ５ F ８ Crystal peak and Y ７ O ６ F ９ The peaks of the crystals overlap. ３ The main peak of Y ５ O ４ F ７ It appears overlapping with the main peak position of Y. ５ O ４ F ７ All peaks at the main peak position of Y ５ O ４ F ７ Treat as a peak of YF ３ If crystals are present, YF ３ The intensity of the peak at around 2θ = 24.5°, which is the second main peak of the crystal, was multiplied by 1.3 to convert it into the main peak equivalent, and this was used as the YF ３ The main peak intensity is the intensity of Y ５ O ４ F ７ The peak (Y ５ O ４ F ７ The YF intensity was calculated by multiplying the YF intensity by 1.3. ３ The intensity of the second main peak of the crystal is subtracted. ３ The intensity (relative intensity) of the second main peak of the crystal is "2.0", and Y ５ O ４ F ７ When the intensity (relative intensity) of the peak at the main peak position of YF is "6.0", ３ Since the intensity of the second main peak of the crystal is converted to "2.6" (= 2.0 × 1.3), Y ５ O ４ F ７ The intensity of the peak at the main peak position of YF after conversion ３The intensity of the second main peak of the crystal is subtracted to obtain "3.4" (=6.0-2.6).

[0031] The XRD pattern of the yttrium-based protective film is obtained by XRD measurement in a micro 2D (two-dimensional) mode using an X-ray diffractometer (D8 DISCOVER Plus, manufactured by Bruker) under the conditions described above.

[0032] (Content of Each Element) When the yttrium-based protective film contains yttrium oxyfluoride, it contains yttrium (Y), oxygen (O), and fluorine (F).

[0033] The Y content of the yttrium-based protective film is preferably 20 atomic % or more, more preferably 25 atomic % or more, even more preferably 27.5 atomic % or more, particularly preferably 30 atomic % or more, and most preferably 31 atomic % or more. On the other hand, the Y content of the yttrium-based protective film is preferably 40 atomic % or less, more preferably 35 atomic % or less, even more preferably 33 atomic % or less, and particularly preferably 32 atomic % or less. The Y content of the yttrium-based protective film is preferably 20 to 40 atomic %, more preferably 25 to 35 atomic %, even more preferably 27.5 to 33 atomic %, particularly preferably 30 to 32 atomic %, and most preferably 31 to 32 atomic %.

[0034] The O content of the yttrium-based protective film is preferably 20 atomic % or more, more preferably 21 atomic % or more, even more preferably 22 atomic % or more, particularly preferably 23 atomic % or more, and most preferably 24 atomic % or more. On the other hand, the O content of the yttrium-based protective film is preferably 35 atomic % or less, more preferably 30 atomic % or less, even more preferably 29 atomic % or less, even more preferably 28 atomic % or less, particularly preferably 27 atomic % or less, and most preferably 26 atomic % or less. The O content of the yttrium-based protective film is preferably 20 to 35 atomic %, more preferably 21 to 30 atomic %, even more preferably 22 to 29 atomic %, even more preferably 23 to 28 atomic %, particularly preferably 24 to 27 atomic %, and most preferably 24 to 26 atomic %.

[0035] The F content of the yttrium protective film is preferably 35 atomic % or more, more preferably 40 atomic % or more, even more preferably 41 atomic % or more, particularly preferably 42 atomic % or more, and most preferably 43 atomic % or more. On the other hand, the F content of the yttrium protective film is preferably 60 atomic % or less, more preferably 55 atomic % or less, even more preferably 50 atomic % or less, even more preferably 48 atomic % or less, particularly preferably 45 atomic % or less, and most preferably 44.5 atomic % or less. The F content of the yttrium protective film is preferably 35 to 60 atomic %, more preferably 40 to 55 atomic %, even more preferably 41 to 50 atomic %, even more preferably 42 to 48 atomic %, particularly preferably 43 to 45 atomic %, and most preferably 43 to 44.5 atomic %.

[0036] In order to set the content of each element within the above range, for example, in the production method described below, the production conditions such as the amount of evaporation source are appropriately adjusted.

[0037] The content (unit: atomic %) of each element in the yttrium protective film is measured using an energy dispersive X-ray analyzer (EX-250SE, manufactured by Horiba, Ltd.).

[0038] <Crystallite size> As mentioned above, for example, particles (particles) that fall off from a member exposed to plasma can adhere to a semiconductor substrate and become foreign matter that causes defects in the circuit. At this time, the smaller the particle size, the more the occurrence of defects can be suppressed. Therefore, the crystallite size of the yttrium protective film is preferably 40.0 nm or less, more preferably 30.0 nm or less, even more preferably 20.0 nm or less, particularly preferably 15.0 nm or less, and most preferably 10.0 nm or less.

[0039] On the other hand, the larger the crystallite size of the yttrium protective film, the smaller the change in crystallite size when heated, making it more stable and improving its thermal cycle resistance. Therefore, the crystallite size of the yttrium protective film is preferably 6.0 nm or more, more preferably 7.0 nm or more, even more preferably 7.5 nm or more, and particularly preferably 8.0 nm or more. The crystallite size of the yttrium protective film is preferably 6.0 to 40.0 nm, more preferably 7.0 to 30.0 nm, even more preferably 7.5 to 20.0 nm, particularly preferably 7.5 to 15.0 nm, and most preferably 8.0 to 10.0 nm.

[0040] In order to set the crystallite size within the above range, it is preferable to produce the yttrium-based protective film by the production method described below.

[0041] The crystallite size of the yttrium-based protective film is determined using Scherrer's equation based on the XRD pattern data obtained by XRD measurement of a mirror-polished yttrium-based protective film.

[0042] <Expansion Coefficient> Because the yttrium-based protective film has superior thermal cycle resistance, the average linear expansion coefficient (also simply referred to as "expansion coefficient") of the yttrium-based protective film at 50 to 500°C is preferably 7.0 ppm / K or more, more preferably 7.5 ppm / K or more, and even more preferably 8.0 ppm / K or more. For the same reasons, the expansion coefficient of the yttrium-based protective film is preferably 10.0 ppm / K or less, more preferably 9.5 ppm / K or less, and even more preferably 9.0 ppm / K or less. The expansion coefficient of the yttrium-based protective film is preferably 7.0 to 10.0 ppm / K, more preferably 7.5 to 9.5 ppm / K, and even more preferably 8.0 to 9.0 ppm / K. The expansion coefficient of the yttrium-based protective film is measured using a thermal dilatometer.

[0043] <Number of Hydrogen Atoms> It is preferable that the number of hydrogen atoms contained in the yttrium-based protective film is small. This results in excellent plasma resistance of the yttrium-based protective film. The reason for this is presumed to be as follows: If there is a large amount of hydrogen in the yttrium-based protective film, this hydrogen is more likely to react with fluorine contained in the plasma (or the gas used to generate the plasma), and as a result, the yttrium-based protective film is more likely to be damaged. On the other hand, if there is less hydrogen in the yttrium-based protective film, the reaction with fluorine is relatively reduced, and damage to the yttrium-based protective film is suppressed.

[0044] Specifically, the number of hydrogen atoms in the yttrium protective film is 5.0×10 ２１ pieces / cm ３ Preferably, 4.5 x 10 ２１ pieces / cm ３ More preferably, 3.5 x 10 ２１ pieces / cm ３ More preferably, 3.0 x 10 ２１ pieces / cm ３ Even more preferably, 2.5×10 ２１ pieces / cm ３ The following is particularly preferred: 2.3 x 10 ２１ pieces / cm ３ The following is particularly preferred: 2.0 x 10 ２１ pieces / cm ３ Highly preferred: 1.9 x 10 ２１ pieces / cm ３ The following are most preferred:

[0045] The hydrogen in the yttrium-based protective film is likely to be due to the influence of moisture contained in the substrate, which will be described later. In particular, when the substrate is made of ceramic, the number of hydrogen atoms in the formed yttrium-based protective film can be reduced by heating (preheating) the substrate before forming the yttrium-based protective film.

[0046] On the other hand, the number of hydrogen atoms in the yttrium protective film is 0.1×10 ２１ pieces / cm ３ More than 0.5 × 10 ２１ pieces / cm ３ The number of hydrogen atoms in the yttrium protective film is more preferably 0.1×10 ２１pieces / cm ３ Above 5.0 x 10 ２１ pieces / cm ３ Preferably, less than 0.5 × 10 ２１ pieces / cm ３ 4.5 x 10 ２１ pieces / cm ３ More preferably, 0.5×10 or less ２１ pieces / cm ３ 3.5 x 10 ２１ pieces / cm ３ More preferably, 0.5 × 10 ２１ pieces / cm ３ Above 3.0 x 10 ２１ pieces / cm ３ Even more preferably, 0.5×10 ２１ pieces / cm ３ 2.5 x 10 ２１ pieces / cm ３ The following is particularly preferred: 0.5 x 10 ２１ pieces / cm ３ 2.3 x 10 ２１ pieces / cm ３ The following is particularly preferred: 0.5 x 10 ２１ pieces / cm ３ Above 2.0 x 10 ２１ pieces / cm ３ Highly preferred: 0.5 x 10 ２１ pieces / cm ３ 1.9 x 10 ２１ pieces / cm ３ The following are most preferred:

[0047] The number of hydrogen atoms in the yttrium protective film was measured using a secondary ion mass spectrometer (model IMS-6f, manufactured by Ametec Co., Ltd.) to measure the number of hydrogen atoms in the yttrium protective film by measuring the primary ion species Cs ＋ The measurement is performed under the conditions of a primary acceleration voltage of 15.0 kV, a detection area of ​​φ8 μm, and a measurement depth of 500 nm.

[0048] <Compressive Stress> The stress (internal stress, residual stress) of the yttrium protective film is preferably compressive stress rather than tensile stress. The compressive stress of the yttrium protective film is preferably 100 MPa or more, more preferably 300 MPa or more, even more preferably 500 MPa or more, particularly preferably 700 MPa or more, and most preferably 1200 MPa or more. On the other hand, the compressive stress of the yttrium protective film is preferably 1700 MPa or less, more preferably 1600 MPa or less, even more preferably 1500 MPa or less, and particularly preferably 1400 MPa or less. The compressive stress of the yttrium protective film is preferably 100 to 1700 MPa, more preferably 300 to 1600 MPa, even more preferably 500 to 1500 MPa, particularly preferably 700 to 1400 MPa, and most preferably 1200 to 1400 MPa.

[0049] The compressive stress of the yttrium-based protective film is determined as follows: A yttrium-based protective film is formed on a quartz glass substrate, and the surface shape of the formed yttrium-based protective film is measured using a surface shape measuring device (Surfcom NEX 241 SD2-13, manufactured by Tokyo Seimitsu Co., Ltd.), and the compressive stress (film stress σ) of the yttrium-based protective film is determined using Stoney's formula (the following formula): σ=Yd ２ / (6c(1-ν)t) In the above formula, σ is film stress, Y is Young's modulus of the substrate, d is thickness of the substrate, ν is Poisson's ratio of the substrate, t is thickness of the yttrium protective film, and c is radius of curvature.

[0050] <Heat Resistance Temperature> The heat resistance temperature of the yttrium-based protective film is preferably 300°C or higher, more preferably 350°C or higher, even more preferably 450°C or higher, even more preferably 500°C or higher, particularly preferably 550°C or higher, very preferably 650°C or higher, and most preferably 750°C or higher.

[0051] In order to set the heat-resistant temperature within the above range, it is preferable to produce an yttrium-based protective film by the production method described below.

[0052] The heat resistance temperature of the yttrium-based protective film is determined by conducting the following test (heat resistance test). First, a sample of a component having an yttrium-based protective film is heated in an air-sintering furnace at a heating rate of 300°C / hr, heated at an arbitrary temperature T for 1 hour, and cooled at 50°C / hr before being removed. An optical microscope is then used to check for the presence or absence of cracks in the yttrium-based protective film. This heat resistance test is conducted at temperatures T from 100°C to 800°C (in 50°C increments), and the highest temperature T at which cracks do not occur is taken as the heat resistance temperature of the yttrium-based protective film.

[0053] [Members] Next, the members of this embodiment will be described. First, the members of this embodiment will be roughly described based on FIG.

[0054] 1 is a schematic diagram showing an example of a member 6. The member 6 has at least a substrate 5 and an yttrium-based protective film 4, in this order. In this embodiment, the yttrium-based protective film of this embodiment described above is used as the yttrium-based protective film 4.

[0055] 1, underlayers (underlayer 1, underlayer 2, and underlayer 3) may be disposed between the substrate 5 and the yttrium-based protective film 4. However, the number of underlayers is not limited to three.

[0056] Each part of the member of this embodiment will be described in detail below.

[0057] <Substrate> The substrate has at least a surface on which the yttrium-based protective film (or underlayer) is to be formed. Hereinafter, this surface may be referred to as the "film formation surface" for convenience.

[0058] <<Material>> The material of the substrate is appropriately selected depending on the application of the member, etc. The substrate is made of, for example, at least one material selected from the group consisting of carbon (C), ceramics, and metals.

[0059] The ceramics include, for example, glass (soda-lime glass, etc.), quartz, aluminum oxide (Al ２ O ３The ceramic is at least one selected from the group consisting of aluminum nitride (AlN), cordierite, yttrium oxide, silicon carbide (SiC), Si-impregnated silicon carbide, silicon nitride (SiN), sialon, and aluminum oxynitride (AlON). The Si-impregnated silicon carbide is obtained by heating and melting elemental Si and impregnating it into silicon carbide (SiC). As the ceramic, at least one selected from the group consisting of glass, quartz, and cordierite is preferred, and quartz is more preferred, because the thermal cycle resistance of the yttrium-based protective film is superior.

[0060] The metal is, for example, at least one selected from the group consisting of aluminum (Al) and alloys containing aluminum (Al).

[0061] <<Shape>> The shape of the substrate is not particularly limited, and examples thereof include a flat plate, a ring, a dome, a concave or a convex shape, and is appropriately selected depending on the use of the member, etc.

[0062] <<Surface roughness of film-forming surface>> The smaller the surface roughness of the film-forming surface of the substrate, the higher the degree of orientation of the yttrium-based protective film formed on the film-forming surface.Therefore, the surface roughness of the film-forming surface of the substrate, as arithmetic mean roughness Ra, is preferably less than 1.00 μm, more preferably 0.60 μm or less, even more preferably 0.40 μm or less, particularly preferably 0.20 μm or less, and most preferably 0.08 μm or less.On the other hand, the lower limit is not particularly limited, and the surface roughness of the film-forming surface of the substrate, as arithmetic mean roughness Ra, is, for example, 0.00005 μm or more, may be 0.001 μm or more, or may be 0.01 μm or more. The surface roughness of the substrate's coating surface may be, for example, 0.00005 μm or more but less than 1.00 μm, 0.001 μm or more but less than 0.60 μm, 0.01 μm or more but less than 0.40 μm, 0.01 μm or more but less than 0.20 μm, or 0.01 μm or more but less than 0.08 μm, as expressed in arithmetic mean roughness Ra. The surface roughness (arithmetic mean roughness Ra) of the coating surface is measured in accordance with JIS B 0601:2001.

[0063] <<Maximum Length of Film-Depositing Surface>> The maximum length of the film-depositing surface of the substrate is preferably 30 mm or more, more preferably 70 mm or more, even more preferably 100 mm or more, particularly preferably 150 mm or more, and most preferably 300 mm or more. The term "maximum length" refers to the maximum length of the film-depositing surface. Specifically, for example, if the film-depositing surface is circular in plan view, it is its diameter; if it is ring in plan view, it is its outer diameter; and if it is rectangular in plan view, it is the length of the largest diagonal. On the other hand, the maximum length of the film-depositing surface is, for example, 2000 mm or less, preferably 1500 mm or less, more preferably 1000 mm or less, even more preferably 700 mm or less, and most preferably 500 mm or less. The maximum length of the film-depositing surface is, for example, 30 to 2000 mm, preferably 70 to 1500 mm, more preferably 100 to 1000 mm, even more preferably 150 to 700 mm, and most preferably 300 to 500 mm.

[0064] 2 is a schematic diagram showing a half-cutout ring-shaped substrate 5. For example, the substrate 5 shown in FIG. １ is 100 mm, inner diameter D ２ When the outer diameter D is 90 mm and the thickness t is 5 mm, the maximum length is 100 mm. １ The film deposition surface 7 may have a first film deposition surface 7a that defines the area of ​​the first film deposition surface 7a and a second film deposition surface 7b that is different from the first film deposition surface 7a. The ratio of the area of ​​the second film deposition surface 7b to the total area of ​​the film deposition surface 7 is, for example, 60% or less.

[0065] Fig. 3 is a schematic diagram showing a part of a cross section of another ring-shaped substrate 5. As shown in Fig. 3, the substrate 5 may have a plurality of second film formation surfaces 7b.

[0066] 4 is a schematic diagram showing a portion of a cross section of yet another ring-shaped substrate 5. The angle between the first film formation surface 7a and the second film formation surface 7b is, for example, 20° to 150°. In the substrate 5 shown in FIG. 4, the angle between the first film formation surface 7a and the second film formation surface 7b connected to the first film formation surface 7a is approximately 30°.

[0067] As described above, an underlayer may be disposed between the substrate and the yttrium-based protective film. By disposing one or more underlayers between the substrate and the yttrium-based protective film, the tensile stress of the yttrium-based protective film is alleviated to generate compressive stress, and the adhesion of the yttrium-based protective film to the substrate is increased.

[0068] <Number of Layers> The number of underlayers is preferably 5 or less, more preferably 4 or less, even more preferably 3 or less, and particularly preferably 2 or less.

[0069] <<Composition>> The underlayer may be, for example, Al ２ O ３ ("β-Al ２ O ３ " (hereinafter the same), SiO ２ , Y ２ O ３ , MgO, CaO, SrO, BaO, B ２ O ３ , SnO ２ , P ２ O ５ , Li ２ O, Na ２ O.K. ２ O, ZrO ２ , La ２ O ３ , Nd ２ O ３ , Yb ２ O ３ , Eu ２ O ３ , Gd ２ O ３ , Ta ２ O ３ , Nb ２ O ５ , HfO ２ , CeO ２ , W.O. ３ , TiO ２ The material contains at least one compound (oxide, oxynitride, nitride) selected from the group consisting of AlON, SiON, AlN, and SiN.

[0070] The compound of the underlayer is Al ２ O ３ , SiO ２ , Y ２ O３ , MgO, CaO, SrO, BaO, B ２ O ３ , SnO ２ , P ２ O ５ , Li ２ O, Na ２ O.K. ２ O, ZrO ２ , La ２ O ３ , Nd ２ O ３ , Yb ２ O ３ , Eu ２ O ３ , Gd ２ O ３ , Ta ２ O ３ , Nb ２ O ５ , HfO ２ , CeO ２ , W.O. ３ and TiO ２ The oxide of the underlayer may be at least one oxide selected from the group consisting of Al ２ O ３ , SiO ２ , Y ２ O ３ , MgO, CaO, SrO, B ２ O ３ and ZrO ２ At least one selected from the group consisting of Al ２ O ３ , SiO ２ , Y ２ O ３ , MgO, CaO, SrO and B ２ O ３ More preferably, at least one selected from the group consisting of Al ２ O ３ , SiO ２ and Y ２ O ３ More preferably, at least one selected from the group consisting of:

[0071] The underlayer is SiO ２ and Y ２ O ３ When containing SiO ２and Y ２ O ３ The molar ratio of (SiO ２ / Y ２ O ３ ) is preferably 90 / 10 to 20 / 80, more preferably 80 / 20 to 30 / 70, and even more preferably 70 / 30 to 40 / 60.

[0072] The compound of the underlayer may be at least one oxynitride selected from the group consisting of AlON and SiON, or at least one nitride selected from the group consisting of AlN and SiN.

[0073] The compound of the underlayer is preferably at least one nitride selected from the group consisting of AlN and SiN, because the yttrium-based protective film has better thermal cycle resistance.

[0074] When two or more underlayers are disposed between the substrate and the yttrium-based protective film, it is preferable that the compounds (oxides, oxynitrides, nitrides) of the underlayers be different from each other in adjacent underlayers. When the compounds of adjacent underlayers are different from each other, for example, when the compound of underlayer 1 is "SiO ２ ", and the compound of the underlayer 2 is "Al ２ O ３ +SiO ２ ", and the compound of the underlayer 3 is "Al ２ O ３ " is one example.

[0075] The content (unit: mol%) of each compound in the underlayer is measured using an energy dispersive X-ray analyzer (EX-250SE, manufactured by Horiba, Ltd.). For example, when the molar ratio of Y to Al to Si (Y / Al / Si) is 25 / 25 / 50 and no elements other than Y, Al, Si, and O are detected, Y is ２ O ３ The content of Al is 25 mol%. ２ O ３ The content of SiO is 25 mol %. ２ The content is assumed to be 50 mol %.

[0076] <<State of Layer>> The underlayer is preferably an amorphous layer, although an amorphous underlayer may contain crystals.

[0077] <<Thickness>> The thickness of each underlayer is preferably 0.05 μm or more, more preferably 0.1 μm or more, even more preferably 0.2 μm or more, even more preferably 0.3 μm or more, and particularly preferably 0.4 μm or more. On the other hand, the thickness of each underlayer is preferably 2.0 μm or less, more preferably 1.8 μm or less, even more preferably 1.6 μm or less, and particularly preferably 1.4 μm or less. The thickness of each underlayer is preferably 0.05 to 2.0 μm, more preferably 0.1 to 1.8 μm, even more preferably 0.2 to 1.6 μm, even more preferably 0.3 to 1.4 μm, and particularly preferably 0.4 to 1.4 μm. The thickness of the underlayer is measured in the same manner as the thickness of the yttrium-based protective film.

[0078] <Use of Member> The member of this embodiment is used, for example, as a member such as a top plate inside 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 use of the member is not limited to these.

[0079] [Method of Manufacturing Yttrium-Based Protective Film and Member] Next, a method of manufacturing the yttrium-based protective film of this embodiment will be described. The following description also serves as a description of a method of manufacturing the member of this embodiment.

[0080] In this embodiment, an ion-assisted deposition (IAD) method is used. Schematically, in a vacuum, an evaporation source (Y ２ O ３ , Y.F. ３ The yttrium protective film is formed by evaporating the yttrium-based protective film.

[0081] By using the IAD method, a very dense yttrium-based protective film can be formed. That is, the resulting yttrium-based protective film has a small porosity. In contrast, yttrium-based protective films obtained by methods such as thermal spraying, aerosol deposition (AD), and ion plating (IP) tend to have many remaining pores.

[0082] <Apparatus Configuration> FIG. 5 is a schematic diagram showing an apparatus used to produce an yttrium-based protective film. The apparatus shown in FIG. 5 has a chamber 11. The interior of the chamber 11 can be evacuated by driving a vacuum pump (not shown). Inside the chamber 11, crucibles 12 and 13 and an ion gun 14 are disposed, and a holder 17 is disposed above them. The holder 17 is integrated with a support shaft 16 and rotates with the rotation of the support shaft 16. A heater 15 is disposed around the holder 17. The holder 17 holds the above-mentioned substrate 5 with its film-forming surface facing downward. The substrate 5 held by the holder 17 rotates with the rotation of the holder 17 while being heated by the heater 15. Furthermore, quartz-crystal film thickness monitors 18 and 19 are attached to the chamber 11.

[0083] <Formation of Yttrium-Based Protective Film (Part 1)> In the apparatus shown in FIG. 5, a protective film of yttrium oxide (Y ２ O ３ First, the evaporation source Y is placed in one or both of the crucibles 12 and 13. ２ O ３ After the substrate 5 is held by the holder 17, the inside of the chamber 11 is evacuated to a vacuum. Next, the heater 15 is driven while the holder 17 is rotated. This causes the substrate 5 to rotate while being heated. In this state, ion-assisted 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 filled in one or both of the crucibles 12 and 13 is evacuated. ２ O ３The evaporation source is melted and evaporated by irradiating it with an electron beam (not shown). In this way, the evaporated evaporation source adheres to the film-forming surface of the substrate 5 (or the surface of the underlayer, if any), and yttrium oxide (Y ２ O ３ ) is formed.

[0084] 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. It is more preferable to use ions of at least two elements selected from the group consisting of oxygen, argon, neon, krypton, and xenon, and it is even more preferable to use oxygen and argon ions in combination.

[0085] <Pressure in the Chamber> Film formation is performed in a vacuum. Specifically, the pressure inside the chamber 11 is 6×10 －２ Pa or less is preferable, and 5 × 10 －２ Pa or less is more preferable, and 3×10 －２ On the other hand, the pressure inside the chamber 11 is preferably 1×10 Pa or less. －６ Pa or more is preferable, and 1×10 －５ Pa or more is preferable, and 1×10 －４ The pressure inside the chamber 11 is preferably 1×10 Pa or more. －６ Pa super 6×10 －２ Pa or less is preferable, and 1×10 －５ Pa or more 5×10 －２ Pa or less is more preferable, and 1×10 －４ Pa or more 3×10 －２ Pa or less is more preferable.

[0086] <<Temperature of the Substrate>> Because it is easy to form an yttrium-based protective film having excellent plasma resistance and thermal cycle resistance, the temperature of the substrate 5 heated by the heater 15 during film formation is preferably 200°C or higher, more preferably 250°C or higher, even more preferably 300°C or higher, particularly preferably 350°C or higher, and most preferably 400°C or higher. On the other hand, this temperature is preferably 700°C or lower, preferably 650°C or lower, and more preferably 600°C or lower. The temperature is preferably 200 to 700°C, more preferably 250 to 650°C, even more preferably 300 to 600°C, particularly preferably 350 to 600°C, and most preferably 400 to 600°C.

[0087] <<Film Formation Rate>> The rate at which the evaporation sources in the crucibles 12 and 13 evaporate and a film is formed (film formation rate) is monitored in advance using quartz film thickness monitors 18 and 19, respectively. The film formation rate is adjusted by controlling the conditions of the electron beam irradiated onto the evaporation sources and the conditions of the ion beam from 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 a desired value.

[0088] Evaporation source Y ２ O ３ The deposition rate of the evaporation source Y is preferably 1.00 nm / min or more, more preferably 1.50 nm / min or more, and even more preferably 2.00 nm / min or more. ２ O ３ The deposition rate of the evaporation source Y is preferably 20.00 nm / min or less, more preferably 15.00 nm / min or less, even more preferably 10.00 nm / min or less, even more preferably 5.00 nm / min or less, and particularly preferably 3.50 nm / min or less. ２ O ３ The film formation rate is preferably 1.00 to 20.00 nm / min, more preferably 1.50 to 15.00 nm / min, even more preferably 2.00 to 10.00 nm / min, still more preferably 2.00 to 5.00 nm / min, and particularly preferably 2.00 to 3.50 nm / min.

[0089] <Ion Irradiation Conditions> The distance between the ion gun 14 and the substrate 5 is preferably 700 mm or more, more preferably 750 mm or more, even more preferably 800 mm or more, and particularly preferably 850 mm or more, because this facilitates the formation of an yttrium-based protective film that has excellent thermal cycle resistance. For the same reasons, the distance between the ion gun 14 and the substrate 5 is preferably 1050 mm or less, and more preferably 1000 mm or less. The distance between the ion gun 14 and the substrate 5 is preferably 700 to 1050 mm, more preferably 750 to 1000 mm, even more preferably 800 to 1000 mm, and particularly preferably 850 to 1000 mm.

[0090] 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. The current value of the ion beam is preferably 1000 to 3000 mA, more preferably 1500 to 2500 mA.

[0091] The current density of the ion beam was 40 μA / cm ２ More than 65 μA / cm is preferable. ２ More preferably, 75 μA / cm ２ More preferably, 77 μA / cm ２ On the other hand, the current density of the ion beam is preferably 140 μA / cm ２ Preferably, 120 μA / cm or less ２ More preferably, 100 μA / cm or less ２ The current density of the ion beam is more preferably 40 to 140 μA / cm ２ is preferred, and 65 to 120 μA / cm ２ More preferably, 75 to 100 μA / cm ２ is more preferably 77 to 100 μA / cm ２ is particularly preferred.

[0092] <<Ar / O Ratio>> As described above, it is preferable to use a combination of argon ions and oxygen ions as ions irradiated from the ion gun 14. In this case, the Ar / O ratio, which is the ratio of the amount of argon (Ar) ions to the amount of oxygen (O) ions, is preferably greater than 2 / 50, more preferably greater than 4 / 50, even more preferably greater than 4 / 50, and particularly preferably greater than 5 / 50. On the other hand, the Ar / O ratio is, for example, 25 / 50 or less, preferably 20 / 50 or less, more preferably 15 / 50 or less, and even more preferably 12 / 50 or less. The Ar / O ratio is preferably greater than 2 / 50 and less than 25 / 50, more preferably 4 / 50 or more and less than 20 / 50, even more preferably greater than 4 / 50 and less than 15 / 50, and particularly preferably 5 / 50 or more and less than 12 / 50.

[0093] The Ar / O ratio is the amount of argon (Ar) ions (unit: W / m) irradiated from the ion gun 14 toward the substrate 5. ２ ), and the amount of oxygen (O) ions (unit: W / m) irradiated from the ion gun 14 toward the substrate 5. ２ ) where "W / m ２ " is a unit of kinetic energy (ion energy flux) across a unit area in a unit time.

[0094] <Formation of Yttrium-Based Protective Film (Part 2)> Next, a case where an yttrium-based protective film (not shown in FIG. 5) containing yttrium oxyfluoride is formed on the substrate 5 will be described. First, an evaporation source Y ２ O ３ The other crucible 13 is filled with evaporation source YF ３ After the substrate 5 is held by the holder 17, the inside of the chamber 11 is evacuated to a vacuum. Next, the heater 15 is driven while the holder 17 is rotated. This causes the substrate 5 to rotate while being heated. In this state, ion-assisted 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 in the crucible 12 is ２ O ３ and the evaporation source YF of the crucible 13 ３The evaporation source is melted and evaporated by irradiating it with an electron beam (not shown). In this way, the evaporated evaporation source adheres to the film formation surface of the substrate 5 (or the surface of the underlayer, if any), and an yttrium-based protective film containing yttrium oxyfluoride is formed.

[0095] The ions irradiated by the ion gun 14 are yttrium oxide (Y ２ O ３ The same applies to the case where a protective film containing yttrium is formed.

[0096] <<Film formation speed>> Evaporation source Y ２ O ３ The deposition rate (unit: nm / min) and the evaporation source YF ３ The film formation rate ratio (Y ２ O ３ / YF ３ ) is preferably 1 / 9.5 or more, more preferably 1 / 8.0 or more, even more preferably 1 / 6.0 or more, even more preferably 1 / 4.5 or more, particularly preferably 1 / 2.0 or more, and most preferably 1 / 1.9 or more. ２ O ３ / YF ３ ) is preferably 1 / 1.0 or less, more preferably 1 / 1.1 or less, even more preferably 1 / 1.2 or less, even more preferably 1 / 1.3 or less, particularly preferably 1 / 1.4 or less, very preferably 1 / 1.5 or less, and most preferably 1 / 1.6 or less. ２ O ３ / YF ３ ) is preferably 1 / 9.5 to 1 / 1.0, more preferably 1 / 8.0 to 1 / 1.1, even more preferably 1 / 6.0 to 1 / 1.2, still more preferably 1 / 4.5 to 1 / 1.3, particularly preferably 1 / 2.0 to 1 / 1.4, very preferably 1 / 1.9 to 1 / 1.5, and most preferably 1 / 1.9 to 1 / 1.6.

[0097] Evaporation source Y ２ O ３ and the deposition rate of the evaporation source YF ３The total rate including the film formation rate of (1) is preferably 5.00 nm / min or more, more preferably 8.00 nm / min or more, and even more preferably 10.00 nm / min or more. On the other hand, this total rate is preferably 50.00 nm / min or less, more preferably 35.00 nm / min or less, and even more preferably 20.00 nm / min or less. The total rate is preferably 5.00 to 50.00 nm / min, more preferably 8.00 to 35.00 nm / min, and even more preferably 10.00 to 20.00 nm / min.

[0098] <<Chamber Pressure, Substrate Temperature, Ion Irradiation Conditions, and Ar / O Ratio>> The chamber pressure, substrate temperature, ion irradiation conditions, and Ar / O ratio when forming an yttrium-based protective film containing yttrium oxyfluoride are determined based on the yttrium oxide (Y ２ O ３ The same applies to the case where a protective film containing yttrium is formed.

[0099] <Formation of Underlayer> Before forming the yttrium-based protective film, one or more of the above-described underlayers (for example, underlayer 1, underlayer 2, and underlayer 3) may be formed on the film-forming surface of the substrate 5.

[0100] The underlayer is formed by ion-assisted deposition, similar to the yttrium protective film. ２ When forming a base layer made of ２ The evaporation source is evaporated while irradiating ions (ion beam) from the ion gun 14, and is then attached to the film-forming surface of the substrate 5. ２ O ３ and SiO ２ When forming an underlayer containing Y, the crucible 12 is charged with Y as an evaporation source. ２ O ３ The crucible 13 is filled with SiO as an evaporation source. ２ The evaporation source is evaporated while irradiating ions (ion beam) from the ion gun 14, and is deposited on the film formation surface of the substrate 5. The conditions for forming the underlayer are the same as those for forming the yttrium-based protective film.

[0101] The substrate may contain water of crystallization. If the moisture resulting from the water of crystallization in the substrate is contained in the yttrium-based protective film to be formed, the number of hydrogen atoms in the yttrium-based protective film is likely to increase.

[0102] Therefore, evaporation source Y ２ O ３ It is preferable to form a base layer on the film-forming surface of the substrate before attaching the base material to the film-forming surface of the substrate (i.e., before forming the yttrium-based protective film). This covers at least the film-forming surface of the substrate, making it difficult for the crystal water of the substrate to be contained in the formed yttrium-based protective film, and thus reducing the number of hydrogen atoms in the yttrium-based protective film, which is preferable.

[0103] <Preheating of Substrate> Because the crystal water of the substrate is less likely to be contained in the yttrium-based protective film, it is preferable to heat the substrate at a high temperature (preheat) before forming the yttrium-based protective film. The preheating temperature is preferably 300°C or higher, more preferably 400°C or higher, even more 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. The preheating temperature is preferably 300 to 800°C, more preferably 400 to 750°C, even more preferably 450 to 700°C, and particularly preferably 500 to 700°C.

[0104] The preheating time is preferably 60 minutes or more, more preferably 120 minutes or more, even more preferably 240 minutes or more, and particularly preferably 480 minutes or more. On the other hand, the preheating time is preferably 1200 minutes or less, more preferably 1000 minutes or less, even more preferably 800 minutes or less, and particularly preferably 600 minutes or less. The preheating time is preferably 60 to 1200 minutes, more preferably 120 to 1000 minutes, even more preferably 240 to 800 minutes, and particularly preferably 480 to 600 minutes.

[0105] The pre-heating atmosphere is, for example, the air atmosphere.

[0106] 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 3 to 8 are examples, and Examples 1 to 2 and Examples 9 to 11 are comparative examples.

[0107] Examples 1 to 11 Using the apparatus described with reference to FIG. 5, members provided with a yttrium-based protective film were manufactured under the conditions shown in Table 1 below.

[0108] The substrate used was a circular substrate (thickness: 10 mm) having a film-forming surface with a diameter (maximum length) shown in Table 1. This substrate was held in a holder in a chamber and preheated in an air atmosphere at the preheating temperature shown in Table 1. The preheating time was 600 minutes.

[0109] Next, an underlayer shown in Table 1 below and an yttrium-based protective film containing yttrium oxide were formed in this order on the film-forming surface of the substrate using the IAD method under the manufacturing conditions shown in Table 1 below. When no underlayer was formed, a "-" was entered in the corresponding column in Table 1 below.

[0110] As a manufacturing condition not listed in Table 1 below, the ion beam current value was 2000 mA. When forming the yttrium-based protective film, argon (Ar) ions and oxygen (O) ions were irradiated from an ion gun toward the substrate at an Ar / O ratio of 6 / 50. When forming the underlayer, only oxygen (O) ions were irradiated from the ion gun.

[0111] The composition of the underlayer is shown in Table 1 below. ２ O ３ +70SiO ２ " is Y ２ O ３ The content is 30 mol%, SiO ２ This means that the content of is 70 mol %.

[0112] In addition, the items listed in Table 1 below were determined for the underlayer and the yttrium-based protective film by the methods described above. The results are shown in Table 1 below. Items that were not measured are marked with "-" in the corresponding column in Table 1 below.

[0113] <Etching Amount> The yttrium-based protective film of each example was subjected to ion etching to evaluate its plasma resistance. Specifically, first, a 10 mm x 5 mm surface of the yttrium-based protective film was mirror-finished, and a part of the mirror-finished surface (referred to as the "test surface") was masked with Kapton tape. Next, using a CCP-type plasma etching device, plasma was generated by discharging in gas under conditions of a pressure of 10 Pa and an RF power of 600 W, and a test (exposure test) was performed in which the test surface was exposed to the generated plasma. More specifically, CF ４ Gas (flow rate: 100 sccm) and O ２ Discharge (generation of plasma) was carried out using a gas (flow rate: 100 sccm), and CF ４ ions were generated. 15-minute discharges (plasma generation) were repeated 10 times, and an exposure test was carried out for a total of 150 minutes. In this way, the unmasked portions of the test surface were etched. Then, a stylus-type surface profiler (Dektak 150, manufactured by ULVAC) was used to measure the step between the masked and unmasked portions of the test surface, thereby determining the amount of etching. The results are shown in Table 1 below. The smaller the amount of etching (unit: nm), the better the plasma resistance can be evaluated.

[0114] <Thermal Cycle Test> Using an electric furnace (SS-2030PKP, manufactured by Tokyo Motoyama Shokai), the members of each example were heated at a heating rate of 4°C / min, heated at an arbitrary temperature T1 for 3 hours, and then cooled at a heating rate of 4°C / min. This constituted one cycle, and 10 cycles were repeated. This thermal cycle test was carried out at the temperature T1 shown in Table 1 below. Thereafter, the presence or absence of cracks in the yttrium protective film was confirmed using an optical microscope. If no cracks occurred, an "A" was recorded, and if cracks occurred, a "B" was recorded in Table 1 below. If no cracks occurred at temperature T1, it can be evaluated as having excellent thermal cycle resistance.

[0115]

[0116] <Summary of Evaluation Results> As shown in Table 1 above, the yttrium-based protective films of Examples 3 to 8 had good plasma resistance and thermal cycle resistance. In contrast, the yttrium-based protective films of Examples 1 and 2 and Examples 9 to 11 had insufficient thermal cycle resistance.

[0117] Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

[0118] This application is based on a Japanese patent application (Patent Application No. 2024-024616) filed on February 21, 2024, the contents of which are incorporated herein by reference.

[0119] 1, 2, 3: Underlayer 4: Yttrium protective film 5: Substrate 6: Member 7: Film formation surface 7a: First film formation surface 7b: Second film formation surface 11: Chamber 12, 13: Crucible 14: Ion gun 15: Heater 16: Support shaft 17: Holder 18, 19: Quartz film thickness monitor

Claims

1. Fracture toughness value is 0.60 MPa m １／２ or more, and having a thickness of 10.0 μm or less.

2. The yttrium-based protective coating according to claim 1, having a porosity of less than 0.50% by volume.

3. The yttrium protective film according to claim 1, wherein the crystallite size is 6.0 nm or more and 40.0 nm or less.

4. The yttrium-based protective film according to claim 1, having an average linear expansion coefficient of 7.0 ppm / K or more and 10.0 ppm / K or less at 50 to 500°C.

5. The number of hydrogen atoms is 5.0 x 10 ２１ pieces / cm ３ 2. The yttrium-based protective film according to claim 1, wherein:

6. The yttrium protective film according to claim 1, having a compressive stress of 100 to 1700 MPa.

7. The yttrium protective film according to claim 1, which has a heat resistance temperature of 500°C or higher.

8. Y ２ O ３ The yttrium-based protective film according to claim 1, comprising:

9. The above Y ２ O ３ 9. The yttrium-based protective film according to claim 8, wherein the degree of orientation of the (222) plane is 50.0% or more.

10. Y in X-ray diffraction patterns ５ O ４ F ７ 2. The yttrium-based protective film according to claim 1, wherein the peak intensity ratio of 11. A member comprising, in this order, a substrate and the yttrium-based protective film according to any one of claims 1 to 10.

12. The member according to claim 11, wherein the substrate is made of at least one material selected from the group consisting of carbon, ceramics, and metals.

13. The member according to claim 12, wherein the ceramic is at least one selected from the group consisting of glass, quartz, and cordierite.

14. The member according to claim 11, further comprising one or more underlayers between the substrate and the yttrium-based protective film.

15. The underlayer is Al ２ O ３ , SiO ２ , Y ２ O ３ , MgO, CaO, SrO, BaO, B ２ O ３ , SnO ２ , P ２ O ５ , Li ２ O, Na ２ O.K. ２ O, ZrO ２ , La ２ O ３ , Nd ２ O ３ , Yb ２ O ３ , Eu ２ O ３ , Gd ２ O ３ , Ta ２ O ３ , Nb ２ O ５ , HfO ２ , CeO ２ , W.O. ３ , TiO ２ 15. The member according to claim 14, comprising at least one compound selected from the group consisting of AlON, SiON, AlN and SiN.

16. The component of claim 11 used inside a plasma processing device.

17. A method for manufacturing the member according to claim 11, comprising irradiating the substrate with ions of at least one element selected from the group consisting of oxygen, argon, neon, krypton, and xenon from an ion gun in a vacuum while evaporating an evaporation source to form the yttrium-based protective film; ２ O ３ , or Y ２ O ３ and Y.F. ３ A method for manufacturing a component using the method.

18. The method for manufacturing a component according to claim 17, wherein the temperature of the substrate is 200° C. or higher during the formation of the yttrium-based protective film.

19. The method for manufacturing a member according to claim 17, wherein one or more underlayers are formed on the surface of the substrate before the yttrium-based protective film is formed.

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