Method for producing corrosion-resistant coating film and method for producing electrostatic chuck device

Abstract

The method for producing a corrosion-resistant coating film comprises: a step for coating a surface of a dielectric substrate with a paste in which particles of a corrosion-resistant material are dispersed, to form a coating of the corrosion-resistant material; and a step for irradiating the coating with laser light and forming a corrosion-resistant coating film by sintering the corrosion-resistant material. The corrosion-resistant material is at least one selection from the group consisting of YOF, YF3, MgF2, and MgAl2O4. The dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

Description

Method for manufacturing corrosion-resistant coating and method for manufacturing electrostatic chuck device

[0001] This application claims priority to Japanese Patent Application No. 2023-203390, filed November 30, 2023, the contents of which are incorporated herein by reference.

[0002] Conventionally, manufacturing lines for semiconductor devices such as ICs, LSIs, and VLSIs include processes that use corrosive halogen-based gases such as fluorine-based gases and chlorine-based gases, or plasmas of these gases. In such processes, for example, after a semiconductor wafer is fixed by an electrostatic chuck device, the wafer may be etched or cleaned (plasma cleaning) using the halogen-based gas or plasma.

[0003] An electrostatic chuck device includes a base body having a main surface serving as a mounting surface on which a wafer is placed, and an electrostatic attraction electrode that generates an electrostatic force (Coulomb force) between the base body and the wafer placed on the mounting surface. The base body is typically made of a ceramic sintered body (dielectric substrate). However, the above-mentioned halogen-based gases and plasmas are known to be highly corrosive to the ceramic members that make up the electrostatic chuck device. Therefore, in processes using the above-mentioned halogen-based gases and plasmas, the electrostatic chuck members are easily worn by the halogen-based gases and plasmas.

[0004] To address the above-mentioned problem, a technique for improving the corrosion resistance of an electrostatic chuck member is known (see, for example, Patent Document 1). Patent Document 1 describes an electrostatic chuck member manufactured using a dielectric substrate containing a highly corrosion-resistant material. The highly corrosion-resistant material is yttrium aluminum garnet (Y ３ Al ５ O １２ , hereinafter abbreviated as YAG), and mixtures in which rare earth oxides other than yttrium oxide are added to YAG, etc. have been disclosed.

[0005] Furthermore, Patent Document 2 discloses a thermally sprayed yttrium-based fluoride coating that is suitably employed as a low-dust-generating corrosion-resistant coating to be provided on parts and the like that are used in a corrosive plasma atmosphere.

[0006] JP 2012-094826 A JP 2017-190475 A

[0007] In recent years, semiconductor devices have become more highly integrated, and semiconductor manufacturing processes have become more diverse. Accordingly, after manufacturing an electrostatic chuck device, it may become necessary to improve the corrosion resistance of the electrostatic chuck member. Therefore, there has been a demand for a technology that can improve the corrosion resistance of the electrostatic chuck device without damaging the electrostatic chuck device. Furthermore, there has been a demand for a method for manufacturing a corrosion-resistant coating that can solve the above-mentioned problems.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a corrosion-resistant coating that can improve the corrosion resistance of a dielectric substrate, and a further object of the present invention is to provide a method for producing an electrostatic chuck member that can improve the corrosion resistance by producing a corrosion-resistant coating using the above method.

[0009] In order to solve the above problems, the present invention includes the following aspects.

[0010] [1] A method for manufacturing a dielectric substrate, comprising the steps of: applying a paste containing dispersed particles of a corrosion-resistant material to a surface of the dielectric substrate to form a coating film of the corrosion-resistant material; and irradiating the coating film with laser light to form a corrosion-resistant coating in which the corrosion-resistant material is sintered, wherein the corrosion-resistant material is YOF, YF ３ , MgF ２ , and MgAl ２ O ４ and the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

[0011] [2] The method for producing a corrosion-resistant coating according to [1], wherein the coating film is formed on only a portion of the surface in the step of forming the coating film.

[0012] [3] A method for forming a corrosion-resistant film on a surface of a dielectric substrate by an aerosol deposition method using fine particles of a corrosion-resistant material, wherein the corrosion-resistant material is YOF, YF ３ , MgF ２ , and MgAl ２ O ４and the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

[0013] [4] The method for producing a corrosion-resistant coating according to [3], wherein the corrosion-resistant coating is formed on a portion of the surface.

[0014] [5] A method for forming a corrosion-resistant film on a surface of a dielectric substrate by a high-frequency magnetron sputtering method using a corrosion-resistant material as a target material, wherein the corrosion-resistant material is YOF, YF ３ , MgF ２ , and MgAl ２ O ４ and the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

[0015] [6] The method for producing a corrosion-resistant coating according to [5], wherein the corrosion-resistant coating is formed on a portion of the surface.

[0016] [7] A method for manufacturing an electrostatic chuck device, comprising: a step of preparing an electrostatic chuck device body having an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body; and a step of forming a corrosion-resistant coating on a surface of the electrostatic chuck member by the method for manufacturing a corrosion-resistant coating according to any one of [1] to [6].

[0017] [8] A method for manufacturing an electrostatic chuck device, comprising: a step of forming a corrosion-resistant coating on a portion of the surface of an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body by the method for manufacturing a corrosion-resistant coating according to any one of [2], [4], and [6]; and a step of manufacturing an electrostatic chuck device including an electrostatic chuck member having the corrosion-resistant coating.

[0018] [9] A method for manufacturing an electrostatic chuck device, comprising the steps of: preparing an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body; and preparing an electrostatic chuck device body including a temperature adjustment member; and forming a corrosion-resistant coating on a surface of the electrostatic chuck member by the method for manufacturing a corrosion-resistant coating described in [5] or [6], wherein the temperature adjustment member is made of a conductive material; and in the step of forming the corrosion-resistant coating, the temperature adjustment member is connected to a high-frequency power source and a high-frequency magnetron sputtering method is performed.

[0019] According to the present invention, it is possible to provide a method for producing a corrosion-resistant coating that can improve the corrosion resistance of a dielectric substrate, and also to provide a method for producing an electrostatic chuck member that can improve the corrosion resistance by producing a corrosion-resistant coating using the above method.

[0020] Fig. 1 is a schematic explanatory view showing an example of a method for manufacturing a corrosion-resistant coating according to a first embodiment. Fig. 2 is a schematic explanatory view showing an example of a method for manufacturing a corrosion-resistant coating according to the first embodiment. Fig. 3 is a schematic explanatory view showing an example of a method for manufacturing a corrosion-resistant coating according to a second embodiment. Fig. 4 is a schematic view showing a preferred example of an electrostatic chuck device main body.

[0021] <Method for Producing a Corrosion-Resistant Coating> [First Embodiment] Hereinafter, a method for producing a corrosion-resistant coating according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. In all of the following drawings, the dimensions and ratios of the components have been appropriately changed to make the drawings easier to understand. The following explanations of the first to third embodiments are provided specifically to facilitate a better understanding of the spirit of the invention, and do not limit the present invention unless otherwise specified. For example, unless otherwise specified, conditions such as materials, amounts, types, numbers, sizes, shapes, positions, and ratios may be changed, added, or omitted as necessary.

[0022] 1 and 2 are explanatory views of a method for manufacturing a corrosion-resistant coating according to the first embodiment. In the method for manufacturing a corrosion-resistant coating according to the present embodiment, first, as shown in FIG. 1, a paste in which particles of a corrosion-resistant material are dispersed is applied to a surface 100a of a dielectric substrate 100 to form a coating 200x of the corrosion-resistant material (coating forming step).

[0023] The dielectric substrate 100 used in this embodiment is made of aluminum oxide (Al ２ O ３ The dielectric substrate 100 is a composite sintered body of black silicon carbide (SiC). The dielectric substrate 100 is colored black due to the inclusion of black SiC.

[0024] The corrosion-resistant material is a material that is resistant to corrosion by corrosive plasma, and examples thereof include YOF (yttrium oxyfluoride), YF ３ , MgF ２ , and MgAl ２ O ４ The YOF is at least one selected from the group consisting of: ##STR1## In addition, commonly used corrosion-resistant materials such as diamond and fluoride compounds can also be applied to the manufacturing method of this embodiment. YOF in the present invention can be selected arbitrarily, and examples include both compounds in which the molar ratio of yttrium (Y), oxygen (O), and fluorine (F) is Y:O:F=1:1:1, and compounds other than 1:1:1. Examples of compounds other than Y:O:F=1:1:1 include Y ５ O ４ F ７ Ya Y ７ O ６ F ９ YOF may consist of only one of these compounds or a combination of two or more of them.

[0025] The specific surface area of ​​the corrosion-resistant material is not particularly limited as long as it can form a corrosion-resistant film, and is, for example, 0.1 m ２ / g to 100m ２ The specific surface area of ​​the particles of the corrosion-resistant material can be, for example, 0.1 m / g, as required. ２ / g to 1.0m ２ / g or 0.5m ２ / g to 5.0m ２ / g or 1.0m ２ / g to 10m ２ / g or 10m ２ / g~25m ２ / g or 25m ２ / g~45m ２ / g or 45m ２ / g~70m ２ / g or 70m ２ / g to 100m ２ / g, etc.

[0026] The paste contains a corrosion-resistant material, which is inorganic particles, and a dispersion medium for dispersing the corrosion-resistant material. The dispersion medium may contain a solvent and a binder. A commercially available solvent for screen printing may also be used as the dispersion medium. The amount of the corrosion-resistant material in the paste can be selected arbitrarily, and examples include, but are not limited to, a mass ratio of 30% to 90%, 40% to 80%, or 50% to 70%.

[0027] The solvent can be arbitrarily selected as needed, and preferred examples of the solvent include diols such as hexylene glycol and propylene glycol, and high-boiling organic solvents such as terpineol and terpenes.

[0028] The binder can be selected arbitrarily as required, and preferred examples include cellulose-based resins such as ethyl cellulose, acrylic resins such as polymethyl methacrylate, and vinyl-based resins such as polyvinyl butyral.

[0029] The dispersion medium may further contain commonly used additives such as leveling agents, chelating agents, surfactants, and thickeners, as appropriate.

[0030] Examples of the leveling agent include water, ethylene glycol, polyethylene glycol, and glycerin.

[0031] Examples of chelating agents include acetylacetone, benzylacetone, and acetic acid.

[0032] These materials are mixed using a dispersing machine selected as needed, such as a three-roll mill, to obtain a paste containing the corrosion-resistant material.

[0033] The resulting paste is applied to the surface 100a of the dielectric substrate 100 to form a coating film 200x. While FIG. 1 illustrates the coating film 200x being formed on a portion of the surface 100a of the dielectric substrate 100 (a portion of the upper surface in FIG. 2), it may also be formed on the entire surface of the dielectric substrate 100. If necessary, it may also be formed on the side or lower surface of the dielectric substrate 100. These may also be combined. The ratio of the area of ​​the portion to the entire surface area of ​​the surface 100a can be selected arbitrarily, for example, 1 to 95%, 5 to 70%, 10 to 50%, or 20 to 30%. The shape formed by the portion can be selected arbitrarily, and may be a shape surrounded by straight lines, a shape surrounded by curved lines, a shape surrounded by a combination of straight lines and curved lines, or an indeterminate shape in plan view. For example, it may be a circle.

[0034] The method for applying the paste is not particularly limited, and any known application method or printing method can be used. Known printing methods include, for example, screen printing and spray coating.

[0035] The applied paste is dried to obtain the coating film 200x. The thickness of the coating film 200x may be appropriately adjusted according to the desired corrosion resistance. For example, the thickness of the coating film 200x may be appropriately determined taking into consideration the desired corrosion resistance and the need for transmission of the laser light L, and may be, for example, 0.1 μm to 200 μm, 0.15 μm to 150 μm, 0.2 μm to 95 μm, 0.3 μm to 90 μm, 0.5 μm to 80 μm, 1 μm to 50 μm, or 5 to 20 μm.

[0036] The method for drying the paste is not particularly limited and can be selected arbitrarily. For example, the paste may be left in an atmosphere at a temperature at which the solvent is removed, for example, at room temperature to 200°C. During drying, air blowing or reduced pressure may be used in combination as appropriate. The temperature may be, for example, 10 to 180°C, 30 to 150°C, 50 to 120°C, or 70 to 100°C.

[0037] Furthermore, in order to remove impurities such as binders contained in the coating film 200x, the applied paste or coating film 200x may be subjected to a degreasing treatment. For example, the degreasing treatment may be performed in an inert atmosphere such as nitrogen or argon at 200°C to 600°C. Typically, such a degreasing treatment also removes the solvent contained in the coating film 200x. The temperature for the degreasing treatment may be 200°C to 330°C, 330°C to 450°C, or 450°C to 600°C.

[0038] That is, to obtain the coating film 200x from the applied paste, the paste may be simply dried, or may be degreased, or may be dried and then degreased.

[0039] Next, as shown in Fig. 2, the coating film 200x is irradiated with laser light L to form a corrosion-resistant coating 200 in which the corrosion-resistant material is sintered (a step of forming a corrosion-resistant coating). Specifically, for example, in the region where the corrosion-resistant coating 200 is to be formed, the coating film 200x is irradiated with the laser light L while being scanned, thereby sintering the particles of the corrosion-resistant material that make up the coating film 200x. In Fig. 2, the light source of the laser light L is indicated by the symbol LS. Any device for irradiating the laser light L can be selected.

[0040] In this embodiment, "irradiating the coating film 200x with the laser light L" may include not only directly irradiating the coating film 200x with the laser light L, but also irradiating a film formed on the surface of the coating film 200x with the laser light L. Specifically, the coating film 200x may be directly irradiated with the laser light L, and / or, if a deposit film of carbon or the like is formed on the surface of the coating film 200x, the deposit film may be irradiated with the laser light L. As a result, the coating film 200x is heated directly by the laser light L or indirectly via the deposit film, and sintering is caused by the heat caused by the laser light L.

[0041] When the coating film 200x is directly irradiated with laser light L, the dielectric substrate 100, which contains black SiC, absorbs the laser light L and generates heat. Therefore, the coating film 200x on the dielectric substrate 100 is sintered by direct heating due to irradiation with the laser light L and heating due to heat transfer from the dielectric substrate 100, and becomes the corrosion-resistant coating 200. Particles made of the corrosion-resistant material bond together, resulting in a sintered film.

[0042] When the laser light L is irradiated directly onto the coating film 200x, the laser light L must be irradiated onto the dielectric substrate 100, and therefore the thickness of the coating film 200x is preferably 95 μm or less.

[0043] Furthermore, in order for the dielectric substrate 100 to absorb the laser light L, it is preferable that the dielectric substrate 100 contains 1 part by mass or more of silicon carbide per 100 parts by mass of aluminum oxide. From the viewpoint of obtaining a desired dielectric constant and volume resistivity, it is preferable that the dielectric substrate 100 contains 1 part by mass or more and 10 parts by mass or less of silicon carbide per 100 parts by mass of aluminum oxide. The amount of silicon carbide may be 2 parts by mass or more and 9 parts by mass or less, 3 parts by mass or more and 7 parts by mass or less, or 4 parts by mass or more and 6 parts by mass or less, for example.

[0044] There is a deposit film provided on the surface of the coating film 200x, and when the laser light L is irradiated onto the deposit film, the deposit film absorbs the laser light L and generates heat.

[0045] Specifically, when a deposit film such as carbon is provided on the coating film 200x and laser light L is irradiated onto it, the deposit film is irradiated with the laser light L and heated, and the coating film 200x is sintered by heat transfer from the deposit film, becoming a corrosion-resistant coating 200.

[0046] Note that a portion of the laser light L may be transmitted through the deposit film and irradiated onto the coating film 200x. In this case, the coating film 200x is sintered by direct heating due to irradiation with the laser light L and by heating due to heat transfer from the deposit film heated by the laser light L, thereby becoming the corrosion-resistant coating 200.

[0047] Furthermore, a portion of the laser light L that reaches the coating film 200x may be transmitted through the coating film 200x and irradiated onto the dielectric substrate 100. In this case, the coating film 200x is sintered by direct heating due to irradiation with the laser light L and heating due to heat transfer from the deposit film heated by the laser light L and the dielectric substrate 100, and becomes the corrosion-resistant coating 200.

[0048] The conditions for irradiating the laser light L are not particularly limited as long as the coating film 200x is sintered to form the corrosion-resistant coating 200. For example, the conditions include irradiating the coating film 200x with an output of 50 W to 1000 W. The output can be selected arbitrarily as needed, and may be 70 W to 800 W, 100 W to 600 W, 200 W to 500 W, 300 W to 400 W, etc. Furthermore, the device for irradiating the laser light can be selected arbitrarily.

[0049] When irradiating the laser light L, irradiation may be started from a position where the coating film 200x is directly irradiated with the laser light L. Alternatively, the laser light L may be irradiated onto the surface 100a of the dielectric substrate 100 exposed in the vicinity of the coating film 200x to first heat the dielectric substrate 100, and then the laser light L may be irradiated onto the coating film 200x while scanning.

[0050] The thickness of the produced corrosion-resistant coating 200 may be, for example, 0.02 μm to 200 μm. If necessary, the thickness may be 0.04 μm to 150 μm, 0.07 μm to 110 μm, 0.08 μm to 90 μm, 0.10 μm to 70 μm, 1 μm to 60 μm, 5 μm to 40 μm, or 10 μm to 20 μm. The thickness of the corrosion-resistant coating 200 can be adjusted by controlling the thickness of the coating film 200x.

[0051] According to the method for producing a corrosion-resistant coating configured as described above, it is possible to provide a method for producing a corrosion-resistant coating that can improve the corrosion resistance of a dielectric substrate.

[0052] For example, if a corrosion-resistant coating is formed by thermal spraying a corrosion-resistant material, the corrosion-resistant material needs to be in a molten or semi-molten state before it is allowed to collide with the dielectric substrate 100. In other words, the corrosion-resistant material that collides with the dielectric substrate 100 is at a temperature high enough to melt it.

[0053] Furthermore, if a corrosion-resistant material is placed on the dielectric substrate 100 and then the entire substrate is heated and sintered using a heating device, the entire dielectric substrate 100 will be heated to a temperature higher than the sintering temperature of the corrosion-resistant material.

[0054] In contrast, in the method for producing a corrosion-resistant coating according to the present embodiment, a coating of the corrosion-resistant material is formed by applying a paste containing the corrosion-resistant material. Furthermore, the corrosion-resistant coating 200 can be produced without heating the dielectric substrate 100 as described above, except for localized heating with laser light L. Therefore, compared to conventionally known methods, the method for producing a corrosion-resistant coating according to the present embodiment makes it possible to improve the corrosion resistance of the dielectric substrate without exposing the dielectric substrate 100 to a stressful heating environment.

[0055] 3 is an explanatory diagram of a method for producing a corrosion-resistant coating according to a second embodiment. In this embodiment, components common to those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

[0056] (Process for forming a corrosion-resistant coating) In the method for manufacturing a corrosion-resistant coating of this embodiment, as shown in Figure 3, a corrosion-resistant coating 200 is formed on the surface 100a of the dielectric substrate 100 by the aerosol deposition method (hereinafter abbreviated as AD method) using fine particles 210 of a corrosion-resistant material (process for forming a corrosion-resistant coating).

[0057] The AD method is a method in which fine particles of a pre-prepared raw material are mixed with a gas to form an aerosol, which is then sprayed onto an object through a nozzle to form a coating. The AD method makes it possible to form a film of a corrosion-resistant material at room temperature. Furthermore, the AD method can form a denser film than films formed by thermal spraying. The shape and number of nozzle openings can be selected arbitrarily, and examples include one or more circles or squares.

[0058] The AD method is carried out using, for example, an aerosol deposition apparatus (hereinafter abbreviated as AD apparatus) 1000 shown in Figure 3. The AD apparatus 1000 has a film formation chamber 1100, a stage 1200, and an ejection unit 1300.

[0059] The film formation chamber 1100 includes a chamber 1110 that accommodates an object (dielectric substrate 100) on which a film is to be formed, and a vacuum pump 1120 that reduces the pressure inside the chamber 1110. When the AD method is performed, the pressure inside the chamber 1110 is reduced by the vacuum pump 1120.

[0060] The stage 1200 is a stage on which the dielectric substrate 100 is placed, and is preferably an XYZθ stage. The XYZθ stage allows fine adjustment in four axes. The stage 1200 can change the position and attitude (angle) of the ejection unit 1300 relative to the nozzle 1320. For example, the stage 1200 can move horizontally left and right or forward and backward as needed, and can be set to any angle (impact angle) within a range of, for example, 0 to 90°, 5 to 75°, 10 to 60°, or 15 to 45°, or a combination thereof. The stage movement speed can also be selected arbitrarily, and may be, for example, 1 to 5000 mm / min, 5 to 1000 mm / min, 10 to 800 mm / min, 100 to 600 mm / min, or 200 to 400 mm / min, but is not limited to these examples.

[0061] The spray unit 1300 has a preparation unit 1310 that prepares an aerosol 220 containing fine particles 210 of a corrosion-resistant material, a nozzle 1320 that sprays the fine particles 210, and a pipe 1330 that connects the preparation unit 1310 and the nozzle 1320. The preparation unit 1310 is disposed outside the chamber 1110, and the nozzle 1320 is disposed inside the chamber 1110, facing the stage 1200. The distance between the nozzle 1320 and the surface 100a of the dielectric substrate 100 can be selected arbitrarily, and may be, for example, 5 mm to 50 mm, 10 mm to 45 mm, or 20 mm to 40 mm. The type of gas to be mixed with the raw material fine particles can be selected arbitrarily, and examples include helium, nitrogen, and argon. For the fine particles 210 of the corrosion-resistant material, the same gases and conditions as those described in the first embodiment may be used, and for example, YOF particles or YF ３The temperature during film formation can be selected arbitrarily, and may be, for example, 0 to 200°C, or may be, for example, 0 to 100°C, 0 to 60°C, 0 to 45°C, 5 to 40°C, or 10 to 35°C. The flow rate of the gas can be set arbitrarily, and may be, for example, 1 to 50 L / min, 5 to 40 L / min, or 10 to 30 L / min, but is not limited to these examples.

[0062] As the AD method, a known method such as the method described in JP-A-2020-525640 can be adopted.

[0063] In the AD method, a coating can be formed by spraying the raw material onto the entire surface of the object, or by spraying the raw material onto a portion of the surface of the object to form a coating on only that region. In Fig. 3, the corrosion-resistant coating 200 is formed on a portion of the surface 100a of the dielectric substrate 100, but it may also be formed on the entire surface of the dielectric substrate 100.

[0064] The particle size range of the corrosion-resistant material particles 210 can be selected arbitrarily, but may be, for example, 0.1 μm to 20 μm, 0.1 μm to 15 μm, 0.1 μm to 10 μm, 0.2 μm to 5 μm, 0.2 μm to 2 μm, 0.3 μm to 1.5 μm, or 0.5 μm to 1.0 μm.

[0065] The thickness of the produced corrosion-resistant coating 200 can be selected arbitrarily and may be, for example, 0.01 μm to 90 μm, 0.1 μm to 60 μm, 1.0 μm to 20 μm, 2 μm to 10 μm, or 3 μm to 7 μm. The thickness of the corrosion-resistant coating 200 can be adjusted by controlling the amount and time of spraying of the fine particles of the raw material.

[0066] If the obtained corrosion-resistant coating 200 does not have sufficient adhesion to the dielectric substrate 100, the corrosion-resistant coating 200 may be further irradiated with laser light as described in the first embodiment to sinter the corrosion-resistant coating 200.

[0067] The method for producing a corrosion-resistant coating configured as described above can also provide a method for producing a corrosion-resistant coating that can improve the corrosion resistance of the dielectric substrate 100. The AD method allows film formation at room temperature, so compared to conventional methods, it is possible to improve the corrosion resistance of the dielectric substrate 100 without exposing the dielectric substrate 100 to a heated environment. Furthermore, even if the corrosion-resistant coating 200 is only a few μm thick, it is possible to form a corrosion-resistant coating that has excellent corrosion resistance and excellent adhesion to the dielectric substrate 100.

[0068] [Third Embodiment] In the method for manufacturing a corrosion-resistant coating of this embodiment, a corrosion-resistant material is used as a target material, and a corrosion-resistant coating 200 is formed on the surface 100a of a dielectric substrate 100 by radio-frequency magnetron sputtering (a corrosion-resistant coating forming step). To facilitate understanding of the invention, the same reference numerals as those in the first and second embodiments are used below.

[0069] The target material may be a sintered body formed using a corrosion-resistant material, an unsintered powdered material formed using a corrosion-resistant material, a compact formed by solidifying the powdered material, a thermally sprayed film formed using a corrosion-resistant material, or a combination thereof. To improve sputtering efficiency, the target material may be a sintered body, with a powder or compact of a corrosion-resistant material disposed on the surface of the sintered body facing the dielectric substrate 100. Alternatively, the target material may be a compact, with a powder of a corrosion-resistant material disposed on the surface of the compact facing the dielectric substrate 100. The target material may be a metal element contained in a compound constituting the corrosion-resistant material. The target material may be composed solely of the metal element. Specific examples of the metal element include Y, Al, and Mg.

[0070] Radio-frequency magnetron sputtering is a sputtering method in which a magnet is placed behind the target and a magnetic field generated on the target surface promotes ionization of plasma gas, thereby improving sputtering efficiency. Radio-frequency magnetron sputtering can be performed using a known radio-frequency magnetron sputtering device. For example, in this embodiment, a dielectric substrate 100 and a target (target material, cathode) with a magnet (e.g., a permanent magnet) on the backside are placed facing each other in a chamber, the chamber is evacuated, and an inert gas or other gas selected as needed is introduced into the chamber. A plasma may be generated by applying a voltage. The resulting positive ions, such as argon ions, may be collided with the surface of the target, and particles sputtered from the target may form a corrosion-resistant coating on the surface of the dielectric substrate 100. If the dielectric substrate 100 is coupled to a temperature-adjusting member (temperature-adjusting base) made of a conductive material, a radio-frequency power source may be connected to the temperature-adjusting member to form the corrosion-resistant coating.

[0071] In the method for manufacturing a corrosion-resistant coating of this embodiment, a corrosion-resistant coating can be formed on the entire surface of the dielectric substrate 100, which is the object, or by masking the dielectric substrate 100, a corrosion-resistant coating can be formed on only a partial area of ​​the surface of the object.

[0072] The method for producing a corrosion-resistant film having the above-described configuration can also provide a method for producing a corrosion-resistant film that can improve the corrosion resistance of the dielectric substrate 100.

[0073] <<Method for Manufacturing Electrostatic Chuck Device>> A method for manufacturing an electrostatic chuck device according to this embodiment includes the steps of: preparing an electrostatic chuck device body including an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body; and forming a corrosion-resistant coating on the surface of the electrostatic chuck member by the method for manufacturing a corrosion-resistant coating described above.

[0074] (Step of Preparing Electrostatic Chuck Device Main Body) First, an electrostatic chuck device main body is prepared as shown in Fig. 4. Fig. 4 is a schematic diagram showing a preferred example of the electrostatic chuck device main body.

[0075] The electrostatic chuck device main body 1 includes an electrostatic chuck member 2 having a disk-like shape in a plan view and one main surface (upper surface) serving as a mounting surface, and a temperature adjustment base 3 having a disk-like shape in a plan view and a predetermined thickness, which is provided below the electrostatic chuck member 2 and adjusts the electrostatic chuck member 2 to a desired temperature. The electrostatic chuck member 2 and the temperature adjustment base 3 are bonded together via an adhesive layer 8 provided between the electrostatic chuck member 2 and the temperature adjustment base 3.

[0076] <Electrostatic Chuck Member> The electrostatic chuck member 2 includes a mounting plate 11 having an upper surface serving as a mounting surface 11a on which a plate-like sample W such as a semiconductor wafer is placed, a support plate 12 integrated with the mounting plate 11 and supporting the bottom side of the mounting plate 11, and an electrostatic attraction electrode 13 provided between the mounting plate 11 and the support plate 12. The electrostatic chuck member 2 may include an insulating layer 14 that insulates the periphery of the electrostatic attraction electrode 13.

[0077] 4, the electrostatic attraction electrode 13 is provided inside the base (between the mounting plate 11 and the support plate 12), but this is not limiting. The electrostatic attraction electrode 13 may be provided on the side opposite to the mounting surface of the base, i.e., below the support plate 12.

[0078] (Placement Plate, Support Plate) The placement plate 11 and the support plate 12 are disk-shaped members with the same shape on the overlapping surfaces. The placement plate 11 and the support plate 12 have excellent mechanical strength and durability against corrosive gases and their plasma. The placement plate 11 and the support plate 12 are made of the above-mentioned Al ２ O ３ In other words, the mounting plate 11 and the support plate 12 correspond to the dielectric substrate 100 on which a corrosion-resistant film can be formed by the method for manufacturing a corrosion-resistant film according to the first and second embodiments.

[0079] A plurality of protrusions 11b, each having a diameter smaller than the thickness of the plate-shaped sample, are formed at predetermined intervals on the mounting surface 11a of the mounting plate 11. These protrusions 11b support the plate-shaped sample W.

[0080] (Electrostatic Adsorption Electrode) The electrostatic adsorption electrode 13 is used to generate an electric charge to generate an electrostatic adsorption force and fix the plate-shaped sample W. The shape and size of the electrode are adjusted appropriately depending on the application.

[0081] The electrostatic attraction electrode 13 is formed from a material arbitrarily selected from among conductive ceramics and metals that are unlikely to be altered or damaged under the conditions of use of the electrostatic chuck device manufactured by the manufacturing method of this embodiment.

[0082] (Insulating Material Layer) The insulating material layer 14 surrounds the electrostatic attraction electrode 13 to protect the electrostatic attraction electrode 13 from corrosive gases and their plasma. The insulating material layer 14 is a layer that bonds and integrates the boundary between the mounting plate 11 and the support plate 12, i.e., the outer peripheral region excluding the electrostatic attraction electrode 13, and is made of an insulating material that has the same composition or the same main component as the material that constitutes the mounting plate 11 and the support plate 12.

[0083] (Temperature Adjusting Base Portion) The temperature adjusting base portion 3 is a thick, disk-shaped member for adjusting the temperature of the electrostatic chuck member 2 to a desired temperature. The body of the temperature adjusting base portion 3 also functions as an internal electrode for generating plasma. The body of the temperature adjusting base member 3 is connected to an external high-frequency power source via a matching box (not shown). As the temperature adjusting base portion 3, for example, a liquid-cooled base or the like having a flow path 3A formed therein for circulating a coolant is suitable.

[0084] If necessary, an insulating plate 7 may be adhered to the upper surface of the temperature adjusting base part 3 via an adhesive layer 6. The temperature adjusting base part 3 can be made of any material, and may be made of metal, conductive ceramics, or metal matrix composite (MMC).

[0085] The adhesive layer 6 is made of a heat-resistant and insulating adhesive resin, such as a sheet- or film-shaped polyimide resin, silicone resin, or epoxy resin.

[0086] The insulating plate 7 is manufactured using an insulating material that is unlikely to deteriorate or break under the conditions of use of the electrostatic chuck device to be manufactured. The insulating plate 7 is made of a thin plate, sheet, or film of a heat-resistant resin such as polyimide resin, epoxy resin, or acrylic resin.

[0087] The electrostatic chuck device body 1 may include a focus ring 10. The focus ring 10 is a member that is placed on the peripheral edge of the temperature adjustment base 3 and has a circular shape in a plan view. The focus ring 10 may be formed, for example, from a material having electrical conductivity equivalent to that of a wafer placed on the mounting surface. By providing such a focus ring 10, the electrical environment relative to the plasma at the peripheral edge of the wafer can be made substantially identical to that of the wafer, thereby making it less likely that a difference or bias in the plasma processing will occur between the central portion and the peripheral portion of the wafer.

[0088] (Other Components) A power supply terminal 15 for applying a DC voltage to the electrostatic attraction electrode 13 is connected to the electrostatic attraction electrode 13. The power supply terminal 15 is inserted into a through-hole 16 that penetrates the temperature adjusting base 3, the adhesive layer 8, and the support plate 12 in the thickness direction. An insulator 15a having insulating properties may be provided on the outer periphery of the power supply terminal 15.

[0089] A heater element 5 may be provided on the lower surface side of the electrostatic chuck member 2. The heater element 5 may be provided inside the electrostatic chuck member 2. The material and shape of the heater element 5 may be selected arbitrarily as long as it is capable of heating the electrostatic chuck member 2. A power supply terminal 17 for supplying power to the heater element 5 is connected to the heater element 5. A cylindrical insulator 18 made of an insulating material may be provided between the power supply terminal 17 and the through hole 3b.

[0090] The heater element 5 is adhered and fixed to the bottom surface of the support plate 12 by an adhesive layer 4 made of a heat-resistant and insulating sheet or film-like silicone resin or acrylic resin with a uniform thickness. The heater element 5 may have any shape.

[0091] A temperature sensor 20 may be provided on the lower surface side of the heater element 5. In the electrostatic chuck device body 1, an installation hole 21 is formed so as to penetrate the temperature adjustment base portion 3 in the thickness direction. The temperature sensor 20 is installed at the top of the installation hole 21. The heater element 5 and the temperature sensor 20 do not need to be in direct contact with each other.

[0092] Furthermore, the electrostatic chuck device body 1 may have a gas hole 28 provided so as to penetrate from the temperature adjustment base 3 to the mounting plate 11 in the thickness direction thereof. A cylindrical insulator 29 may be provided on the inner periphery of the gas hole 28.

[0093] A gas supply device (cooling means) is connected to the gas hole 28. A cooling gas (heat transfer gas) for cooling the plate-shaped sample W is supplied from the gas supply device through the gas hole 28. The cooling gas is supplied through the gas hole to the grooves 19 formed between the plurality of protrusions 11b on the upper surface of the mounting plate 11, thereby cooling the plate-shaped sample W.

[0094] Furthermore, the electrostatic chuck device main body 1 has pin insertion holes (not shown) that are provided so as to penetrate from the temperature control base 3 to the mounting plate 11 in the thickness direction thereof. The pin insertion holes may have a structure similar to that of the gas holes 28, for example. Lift pins for detaching the plate-shaped sample are inserted into the pin insertion holes. The electrostatic chuck device main body 1 has the above-described structure.

[0095] (Step of forming a corrosion-resistant coating) Next, a corrosion-resistant coating, specifically an Al coating, is formed on the surface of the electrostatic chuck member 2 by the above-described method for producing a corrosion-resistant coating. ２ O ３ A corrosion-resistant coating is formed on the surface of the mounting plate 11 and / or the support plate 12 made of a SiC composite sintered body (a step of forming a corrosion-resistant coating).

[0096] When the corrosion-resistant coating is formed by the method of the first embodiment, the dispersant used in the coating and the method for forming the coating are not particularly limited as long as they do not damage or deteriorate the components of the electrostatic chuck device body 1 and do not affect the use. When the corrosion-resistant coating is formed by the method of the third embodiment, the temperature adjustment member 3 can be connected to a high-frequency power source.

[0097] The corrosion-resistant coating is preferably provided on a portion of the electrostatic chuck device that is exposed to plasma. The location where the corrosion-resistant coating is provided can be selected arbitrarily. For example, the corrosion-resistant coating is preferably provided on the surface and side surfaces of the electrostatic chuck device body 1 and / or the surface and side surfaces of the electrostatic chuck member 2.

[0098] By using the above-mentioned methods (laser light sintering, AD method, magnetron sputtering method), the corrosion-resistant coating can be provided on a surface other than the dielectric substrate 100. The corrosion-resistant coating may be provided, for example, on focus ring 10 exposed to plasma, the side surface of temperature-adjusting base 3, or the like.

[0099] The methods for manufacturing a corrosion-resistant coating according to the first, second, and third embodiments described above are all capable of forming a corrosion-resistant coating without exposing the dielectric substrate 100 to a stressful heating environment. Therefore, even when forming a corrosion-resistant coating on the electrostatic chuck device body 1, the corrosion-resistant coating can be formed without exposing the electrostatic chuck device body 1 to a heating environment, and the corrosion resistance of the electrostatic chuck device body 1 can be improved without damaging device components such as wiring of the electrostatic chuck device body 1.

[0100] Furthermore, the methods for manufacturing a corrosion-resistant coating according to the first and second embodiments described above also enable the formation of a corrosion-resistant coating at desired positions. Therefore, by selectively forming a corrosion-resistant coating at a portion of an electrostatic chuck device that is susceptible to wear in a plasma process, it is possible to particularly improve the corrosion resistance of the portion that is susceptible to wear in the plasma process. A step of identifying in advance the portion of the electrostatic chuck device that is susceptible to wear in the plasma process may be included.

[0101] Furthermore, for an electrostatic chuck device that has been worn out during use in a plasma process, by forming a corrosion-resistant coating again on the worn out portion, the worn out portion can be easily repaired, and the device can be used for a long period of time. In other words, the method may further include a repair step of repairing the worn out portion of the electrostatic chuck device.

[0102] According to the method for manufacturing an electrostatic chuck device having the above-described configuration, it is possible to improve the corrosion resistance of the electrostatic chuck device.

[0103] In this embodiment, the electrostatic chuck device body 1 is prepared, and then the corrosion-resistant coating is formed on the electrostatic chuck member of the electrostatic chuck device body 1, but the present invention is not limited to this.

[0104] For example, Al ２ O ３ After forming a corrosion-resistant coating on a portion of the surface of the electrostatic chuck member 2 made of a -SiC composite sintered body, this electrostatic chuck member 2 may be used to manufacture an electrostatic chuck device including the electrostatic chuck member 2 having the corrosion-resistant coating.

[0105] Even with this manufacturing method, it is possible to selectively form a corrosion-resistant coating on portions of an electrostatic chuck device that are prone to wear in a plasma process, thereby particularly improving the corrosion resistance of the portions that are prone to wear in a plasma process.

[0106] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. The shapes and combinations of the components shown in the above examples are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0107] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0108] In this example, the following test piece was used as a model experiment to confirm that a corrosion-resistant film can be formed. Test piece: Dielectric substrate (Al ２ O ３ : SiC = 95:5 (mass ratio), circular, thickness 20 mm)

[0109] Example 1: Yttrium oxyfluoride particles (YOF, specific surface area 4.7 m), which are corrosion-resistant materials, were used. ２ / g) was added to a solvent for screen printing so that the concentration was 70 mass %, and the mixture was dispersed using a triple roll mill to obtain a paste in which particles of the corrosion-resistant material were dispersed.

[0110] The obtained paste was applied to a test piece by screen printing to form a coating film having a dry thickness of 15 μm. The obtained coating film was irradiated with a 400 W laser to sinter the coating film, thereby obtaining the corrosion-resistant coating of Example 1.

[0111] Example 2: Corrosion-resistant material, yttrium fluoride particles (YF ３ , specific surface area 8.2m ２ The corrosion-resistant coating of Example 2 was obtained in the same manner as in Example 1, except that a 100% by weight of ZnO was used and the content of the corrosion-resistant material in the paste was 60 mass %.

[0112] [Example 3] Spinel particles (MgAl ２ O ４ , specific surface area 2.9m ２ The corrosion-resistant coating of Example 3 was obtained in the same manner as in Example 1, except that a 100% by weight of 100% by weight of the corrosion-resistant material was used and the content of the corrosion-resistant material in the paste was 54 mass %.

[0113] Example 4: Yttrium oxyfluoride particles (YOF, specific surface area 1.9 m), which are corrosion-resistant materials, were used. ２ The corrosion-resistant coating of Example 4 was formed on a test piece by aerosol deposition using a 1000 vol. / g solution of 1000 vol. / g ...

[0114] As shown in Examples 1 to 4, Al ２ O ３ It has been confirmed that a corrosion-resistant coating can be formed on a dielectric substrate made of silicon dioxide and silicon carbide (SiC) by screen printing and laser irradiation or aerosol deposition.

[0115] From the above investigation, it was confirmed that the present invention is useful.

[0116] REFERENCE SIGNS LIST 1 Electrostatic chuck device main body 2 Electrostatic chuck member 3 Temperature adjustment base portion 3A Flow path 3b Through hole 4 Adhesive layer 5 Heater element 6 Adhesive layer 7 Insulating plate 8 Adhesive layer 10 Focus ring 11 Mounting plate 11a Mounting surface 11b Protrusion 12 Support plate 13 Electrostatic attraction electrode 14 Insulating material layer 15 Power supply terminal 15a Insulator 16 Through hole 17 Power supply terminal 18 Insulator 19 Groove 20 Temperature sensor 21 Installation hole 28 Gas hole 29 Insulator 2O4 MgAl 100 Dielectric substrate 100a Surface 200 Corrosion-resistant coating 200x Coating film 210 Fine particles 220 Aerosol 1000 Aerosol deposition device 1100 Film-forming chamber 1110 Chamber 1120 Vacuum pump 1200 Stage 1300 Spraying section 1310 Preparation section 1320 Nozzle 1330 Piping L Laser light LS Laser light source W Plate-shaped sample

Claims

1. A method for manufacturing a dielectric substrate, comprising the steps of: applying a paste having particles of a corrosion-resistant material dispersed therein to a surface of the dielectric substrate to form a coating film of the corrosion-resistant material; and irradiating the coating film with a laser beam to form a corrosion-resistant coating in which the corrosion-resistant material is sintered. The corrosion-resistant material is selected from the group consisting of YOF, YF ３ , MgF ２ , and MgAl ２ O ４ wherein the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

2. The method for producing a corrosion-resistant coating according to claim 1, wherein in the step of forming the coating film, the coating film is formed on only a portion of the surface.

3. A process for forming a corrosion-resistant film on the surface of a dielectric substrate by an aerosol deposition method using fine particles of a corrosion-resistant material, the corrosion-resistant material being YOF, YF ３ , MgF ２ , and MgAl ２ O ４ wherein the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

4. The method for producing a corrosion-resistant coating according to claim 3, wherein the corrosion-resistant coating is formed on a portion of the surface.

5. A process for forming a corrosion-resistant film on the surface of a dielectric substrate by a high-frequency magnetron sputtering method using a corrosion-resistant material as a target material, wherein the corrosion-resistant material is YOF, YF ３ , MgF ２ , and MgAl ２ O ４ wherein the dielectric substrate is an aluminum oxide-silicon carbide composite sintered body.

6. A method for producing a corrosion-resistant coating according to claim 5, wherein the corrosion-resistant coating is formed on a portion of the surface.

7. A method for manufacturing an electrostatic chuck device, comprising the steps of: preparing an electrostatic chuck device body having an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body; and forming a corrosion-resistant coating on a surface of the electrostatic chuck member by the method for manufacturing a corrosion-resistant coating according to any one of claims 1 to 6.

8. A method for manufacturing an electrostatic chuck device, comprising the steps of: forming a corrosion-resistant coating on a portion of the surface of an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body by the method for manufacturing a corrosion-resistant coating as defined in any one of claims 2, 4 and 6; and manufacturing an electrostatic chuck device comprising an electrostatic chuck member having the corrosion-resistant coating.

9. A method for manufacturing an electrostatic chuck device, comprising the steps of: preparing an electrostatic chuck member made of an aluminum oxide-silicon carbide composite sintered body; and preparing an electrostatic chuck device body having a temperature adjustment member; and forming a corrosion-resistant coating on a surface of the electrostatic chuck member by the method for manufacturing a corrosion-resistant coating according to claim 5 or 6, wherein the temperature adjustment member is made of a conductive material, and in the step of forming the corrosion-resistant coating, the temperature adjustment member is connected to a high-frequency power source and a high-frequency magnetron sputtering method is performed.

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