JP2016102264A - Plasma resistant member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma resistant member which can reduce particles and stably maintain a chamber condition.SOLUTION: A plasma resistant member includes: a base material; and a plasma resistant layer structure including a yttria polycrystal formed on a surface of the base material by an aerosol deposition method. The yttria polycrystal constituting the layer structure has a crystal structure in which a cubic crystal and a monoclinic crystal are present in a mixed state. A ratio of the monoclinic crystal to the cubic crystal in the yttria polycrystal constituting the layer structure is 0% or more and 60% or less. A crystallite size of the yttria polycrystal constituting the layer structure is 8 nm or more and 50 nm or less.SELECTED DRAWING: Figure 1

Description

  Aspects of the present invention generally relate to a plasma-resistant member, and more specifically to a plasma-resistant member used in a semiconductor manufacturing apparatus that performs processes such as dry etching, ashing, sputtering, and CVD in a chamber.

  2. Description of the Related Art In a semiconductor manufacturing process, improvement in yield and reduction in yield due to reduction in defects of devices to be manufactured are required.

  On the other hand, there is an apparatus for manufacturing an electronic device in which the ceiling portion of the chamber is made of quartz glass, and the average surface roughness of the minute irregularities formed on the inner surface of the ceiling portion is 0.2 to 5 μm (Patent Document) 1). In addition, there is a plasma-resistant member that does not have pores or grain boundary layers and suppresses or reduces the occurrence of degranulation from the plasma-resistant member (Patent Document 2).

  During the semiconductor manufacturing process, in order to improve the yield by reducing the defects of the manufactured device, the inner wall of the chamber is coated with an yttria film having excellent plasma resistance to reduce the generation of particles. In recent years, finer patterning of semiconductor devices has progressed, and stable control of particles at the nano level is required.

Japanese Patent No. 3251215 Japanese Patent No. 3864958

  It is an object of the present invention to provide a plasma-resistant member that can reduce particles and stably maintain chamber conditions.

  1st invention comprises a base material, and the layered structure which has a yttria polycrystal formed in the surface of the said base material by the aerosol deposition method, and has plasma resistance, The said layered structure is comprised. The yttria polycrystal has a crystal structure in which a cubic crystal and a monoclinic crystal are mixed, and the ratio of the monoclinic crystal to the cubic crystal in the yttria polycrystal constituting the layered structure is 0% or more and 60 %, And the crystallite size of the yttria polycrystal constituting the layered structure is 8 nm or more and 50 nm or less.

According to this plasma-resistant member, the layered structure has a dense structure as compared with the yttria fired body, the yttria sprayed film, and the like. Thereby, the plasma resistance of the plasma-resistant member is higher than the plasma resistance of the fired body or the sprayed film. In addition, the probability that the plasma-resistant member becomes a particle generation source is lower than the probability that the fired body or the sprayed film becomes a particle generation source. Thereby, while maintaining the plasma resistance of a plasma-resistant member, a particle can be reduced. In addition, since the crystallite size of the yttria polycrystal constituting the layered structure is as small as 50 nm or less, particles generated in the chamber during the semiconductor manufacturing process can be reduced. The crystallite size of the yttria polycrystal constituting the layered structure is preferably 20 nm or more and 35 nm or less, more preferably 8 nm or more and 25 nm or less.
In addition, by setting the ratio of monoclinic crystal to cubic crystal to 60% or less, the chemical resistance of the layered structure can be maintained after chemical cleaning during maintenance. The ratio of the monoclinic crystal to the cubic crystal is preferably 20% or more and 40% or less, more preferably 0% or more and 5% or less. By maintaining the chemical resistance of the plasma resistant member mounted in the chamber, the surface state does not change due to erosion, so that the state of plasma generated in the chamber can be stabilized. Thereby, particles generated during the semiconductor manufacturing process can be reduced, and the chamber condition can be stably maintained.

  The second invention is the plasma-resistant member according to the first invention, wherein an interval between adjacent crystallites in the yttria polycrystal constituting the layered structure is 0 nm or more and less than 10 nm. It is.

  According to this plasma-resistant member, the fine structure of the layered structure becomes clearer. In the yttria polycrystal constituting the layered structure, the distance between adjacent crystallites is as small as less than 10 nm, and the voids from which corrosion starts are very small, so that particles can be reduced. In addition, since the structure is dense, chemical penetration into the layered structure can be suppressed after chemical cleaning during maintenance, and thus the chemical resistance of the layered structure can be maintained. Thereby, particles generated during the semiconductor manufacturing process can be reduced, and the chamber condition can be stably maintained.

  According to a third invention, in the first or second invention, the atomic number concentration of oxygen (O) relative to the atomic concentration (atm%) of yttrium (Y) in the yttria polycrystal constituting the layered structure. Is a plasma-resistant member characterized by having a ratio of 1.3 to 1.8.

  According to this plasma-resistant member, since the bonds between yttria particles become stronger, particles can be reduced. In addition, since the structure is denser, chemical penetration into the layered structure can be suppressed after chemical cleaning during maintenance, and thus the chemical resistance of the layered structure can be maintained. Thereby, particles generated during the semiconductor manufacturing process can be reduced, and the chamber condition can be stably maintained.

  According to a fourth invention, in any one of the first to third inventions, the lattice strain of the yttria polycrystal constituting the layered structure is 0% or more and 1.3% or less. It is a plasma resistant member.

  According to this plasma-resistant member, the chemical resistance of the layered structure is maintained after chemical cleaning during maintenance while maintaining the fine crystallite size of the yttria polycrystals constituting the layered structure. can do. Thereby, particles generated during the semiconductor manufacturing process can be reduced, and the chamber condition can be stably maintained.

  A fifth invention is the plasma-resistant member according to any one of the first to fourth inventions, wherein the layered structure is formed by a heat treatment.

  According to the plasma-resistant member, particles generated during the semiconductor manufacturing process can be reduced, and a more preferable layered structure for stably maintaining the chamber condition can be obtained.

  According to the aspect of the present invention, there is provided a plasma-resistant member capable of reducing particles and stably maintaining chamber conditions.

It is typical sectional drawing showing the semiconductor manufacturing apparatus provided with the plasma-resistant member concerning embodiment of this invention. It is a photograph figure showing the surface of the layered structure formed in the surface of a plasma-resistant member. It is the table | surface showing the relationship between the structure of the layered structure formed in the surface of a plasma-resistant member, and chemical resistance. It is a photograph figure showing the surface of the layered structure formed in the surface of a plasma-resistant member. It is a schematic diagram explaining a three-dimensional surface property parameter.

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
FIG. 1 is a schematic cross-sectional view showing a semiconductor manufacturing apparatus provided with a plasma-resistant member according to an embodiment of the present invention.
The semiconductor manufacturing apparatus 100 illustrated in FIG. 1 includes a chamber 110, a plasma resistant member 120, and an electrostatic chuck 160. The plasma-resistant member 120 is called, for example, a top plate or the like, and is provided in the upper part inside the chamber 110. The electrostatic chuck 160 is provided in the lower part inside the chamber 110. That is, the plasma resistant member 120 is provided on the electrostatic chuck 160 inside the chamber 110. An object to be attracted such as the wafer 210 is placed on the electrostatic chuck 160.

The plasma-resistant member 120 has, for example, a structure in which a layered structure 123 including a yttria (Y ₂ O ₃ ) polycrystal is formed on the surface of a base material including alumina (Al ₂ O ₃ ). The layered structure 123 of yttria polycrystal is formed by the “aerosol deposition method”. The material of the substrate is not limited to ceramics such as alumina, and may be quartz, anodized, metal or glass.

  In the “Aerosol Deposition Method”, “Aerosol”, in which fine particles containing brittle materials are dispersed in a gas, is sprayed from a nozzle toward the base material, causing the fine particles to collide with a base material such as metal, glass, ceramics or plastic. A method of directly forming a layered structure (also referred to as a film-like structure) 123 made of a constituent material of fine particles on a base material by causing deformation and crushing of the brittle material fine particles by the impact of the collision and joining them. It is. According to this method, the layered structure 123 can be formed at room temperature without requiring any heating means or cooling means, and the layered structure 123 having mechanical strength equal to or higher than that of the fired body can be obtained. it can. In addition, the density, mechanical strength, electrical characteristics, and the like of the layered structure 123 can be changed in various ways by controlling the conditions under which the fine particles collide and the shape and composition of the fine particles.

  In the present specification, “polycrystal” refers to a structure formed by bonding and accumulating crystal particles. The crystal particles are substantially one and constitute a crystal. The diameter of the crystal particles is usually 5 nanometers (nm) or more. However, when the fine particles are taken into the structure without being crushed, the crystal particles are polycrystalline.

  In the present specification, the term “fine particles” means that when the primary particles are dense particles, the average particle diameter identified by particle size distribution measurement or scanning electron microscope is 5 micrometers (μm) or less. Say. When the primary particles are porous particles that are easily crushed by impact, the average particle size is 50 μm or less.

  In the specification of the present application, “aerosol” refers to a solid-gas mixed phase body in which the aforementioned fine particles are dispersed in a gas such as helium, nitrogen, argon, oxygen, dry air, or a mixed gas containing these. Although it may contain an “aggregate”, it means a state in which fine particles are dispersed substantially alone. The gas pressure and temperature of the aerosol are arbitrary, but the concentration of fine particles in the gas is 0.0003 mL / L at the time when the gas is injected from the discharge port when the gas pressure is converted to 1 atm and the temperature is converted to 20 degrees Celsius. It is desirable for the formation of the layered structure 123 to be in the range of ˜5 mL / L.

The aerosol deposition process is usually performed at room temperature, and has one feature that the layered structure 123 can be formed at a temperature sufficiently lower than the melting point of the fine particle material, that is, at a temperature of 100 degrees centigrade or less.
In the present specification, “normal temperature” refers to a room temperature environment that is substantially lower than the sintering temperature of ceramics and is substantially 0 to 100 ° C.

The fine particles constituting the powder as the raw material of the layered structure 123 are mainly brittle materials such as ceramics and semiconductors, and the fine particles of the same material can be used alone or mixed with fine particles having different particle diameters. Different brittle material fine particles can be mixed or combined to be used. Moreover, it is also possible to mix fine particles such as metal materials and organic materials with brittle material fine particles, or to coat the surface of brittle material fine particles. Even in these cases, the main component of the formation of the layered structure 123 is a brittle material.
In the present specification, “powder” refers to a state in which the above-mentioned fine particles are naturally agglomerated.

  In the composite structure formed by this method, when crystalline brittle material fine particles are used as a raw material, the layered structure 123 portion of the composite structure is a polycrystalline body whose crystal particle size is smaller than that of the raw material fine particles. In many cases, the crystal has substantially no crystal orientation. Moreover, the grain boundary layer which consists of a glass layer does not exist substantially in the interface of brittle material crystals. In many cases, the layered structure 123 portion of the composite structure forms an “anchor layer” that bites into the surface of the substrate. The layered structure 123 in which the anchor layer is formed is formed by being firmly attached to the base material with extremely high strength.

  In the aerosol deposition method, the brittle material fine particles that have come to the surface are crushed and deformed on the substrate. The brittle material fine particles used as the raw material and the crystallites (crystal particles of the formed brittle material structure) ) The size can be confirmed by measuring by an X-ray diffraction method or the like. That is, the crystallite size of the layered structure 123 formed by the aerosol deposition method is smaller than the crystallite size of the raw material fine particles. The “developed surface” or “fracture surface” formed by crushing or deforming fine particles is a “new surface” in which atoms that were originally present inside the fine particles and bonded to other atoms are exposed. Is formed. It is considered that the layered structure 123 is formed by joining this new surface having high surface energy and activity to the surface of the adjacent brittle material fine particles, the new surface of the adjacent brittle material, or the surface of the substrate.

  In the semiconductor manufacturing apparatus 100, high-frequency power is supplied, and a source gas such as a halogen-based gas is introduced into the chamber 110 as indicated by an arrow A1 shown in FIG. Then, the source gas introduced into the chamber 110 is turned into plasma in a region 191 between the electrostatic chuck 160 and the plasma resistant member 120.

  The plasma resistant member 120 is one of important members for generating high density plasma. Here, when the particles 221 generated inside the chamber 110 adhere to the wafer 210, a defect may occur in the manufactured semiconductor device. Then, the yield and productivity of the semiconductor device may be reduced. Therefore, the plasma resistance member 120 is required to have plasma resistance.

  The plasma-resistant member 120 of this embodiment has a structure in which a layered structure 123 containing a yttria polycrystal is formed on the surface of a substrate containing alumina by an aerosol deposition method. The layered structure 123 of the yttria polycrystal formed by the aerosol deposition method has a dense structure as compared with the yttria fired body or the yttria sprayed film. Thereby, the plasma resistance of the plasma-resistant member 120 of this embodiment is higher than the plasma resistance of a fired body or a sprayed film. In addition, the probability that the plasma-resistant member 120 of this embodiment is a particle generation source is lower than the probability that a fired body or a sprayed coating is a particle generation source. Moreover, in order to densify the layered structure 123 containing the yttria polycrystal, fine particles that function as film forming auxiliary particles may be used. Here, the film-forming auxiliary particles are for deforming or crushing yttria fine particles to form a new surface, and after the collision, they are directly reflected in the constituent material of the layered structure except those that are reflected and inevitably mixed. Must not.

The layered structure 123 according to the present embodiment refers to a dense layered structure having a density of 70% or more, preferably 90% or more, more preferably 99% or more.
Here, the density (%) is (bulk specific gravity / true specific gravity) × 100 (true bulk density obtained from the literature value or theoretical calculation value and the bulk specific gravity determined from the mass and volume of the layered structure 123). %). In addition, when it is difficult to measure the weight or volume of the layered structure 123, cross-sectional observation is performed using, for example, a scanning electron microscope (SEM), and the volume of the pore portion in the layered structure is determined. The density may be calculated from the three-dimensional image analysis.

  Furthermore, the plasma-resistant member 120 of this embodiment has a roughened surface as shown in FIG. According to this, the present inventor has obtained knowledge that particles can be reduced while maintaining the plasma resistance of the plasma resistant member 120. Hereinafter, the layered structure 123 formed on the surface of the plasma resistant member 120 of the present embodiment will be described with reference to the drawings.

The present inventor performed heat treatment on the layered structure formed on the surface of the plasma-resistant member 120 and then performed chemical treatment to roughen the surface of the layered structure 123. The layered structure subjected to the heat treatment has a dense structure.
In this specification, “heat treatment” refers to heat treatment of an object using a dryer, oven, baking furnace, laser, electron beam, ion beam, molecular beam, atomic beam, high frequency, plasma, or the like. Further, the heat treatment may be performed during or after the process of manufacturing the layered structure.
In the specification of the present application, “chemical treatment” means that the surface of an object is treated with a material that generates hydrogen ions in an aqueous solution. For example, chemical treatment includes hydrobromic acid, hydroiodic acid, hypochlorous acid, chlorous acid, chloric acid, perchloric acid, sulfuric acid, fluorosulfonic acid, nitric acid, hydrochloric acid, phosphoric acid, hexafluoroantimony Acid, tetrafluoroboric acid, hexafluorophosphoric acid, chromic acid, boric acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, polystyrenesulfonic acid, acetic acid, citric acid, Examples include surface treatment using an aqueous solution containing at least one of formic acid, gluconic acid, lactic acid, oxalic acid, tartaric acid, hydrofluoric acid, carbonic acid, and hydrogen sulfide.
Alternatively, “chemical treatment” in the present specification means that the surface of an object is treated with a substance that generates hydroxide ions in an aqueous solution. For example, the chemical treatment includes surface treatment using an aqueous solution containing at least one of sodium hydroxide, potassium hydroxide, ammonia, calcium hydroxide, barium hydroxide, copper hydroxide, aluminum hydroxide, and iron hydroxide. Can be mentioned.
Then, the inventor observed the surface of the layered structure 123 subjected to the chemical treatment after the heat treatment. The photograph is as shown in FIG.
Note that the present invention is not limited to the case where the surface of the layered structure 123 is roughened, and even in the case of as-deposition immediately after film formation, it is a case where a polishing process is performed after film formation. It applies even if it exists.

FIG. 3 is a table showing the relationship between the heat treatment temperature of the layered structure 123, the structure of the layered structure, and the chemical resistance.
The inventor of this application evaluated the crystal structure and chemical resistance of each of the samples 1 to 5.
Sample 1 is a layered structure 123 that is formed by the aerosol deposition method and not subjected to heat treatment. Samples 2 to 5 were formed by the aerosol deposition method and then subjected to heat treatment at 200 ° C. for 2 hours, 300 ° C. for 2 hours, 400 ° C. for 2 hours, and 600 ° C. for 2 hours, respectively. This is a structure 123.

As the evaluation of the structure of the layered structure 123, the ratio of monoclinic crystal (M) to cubic crystal (C) (M / C) × 100 (%), crystallite size (nm), lattice strain (%), and The atomic number concentration ratio of oxygen (O) to yttrium (Y) was evaluated.
As an evaluation of chemical resistance, the variation in the surface roughness of the layered structure 123 after the layered structure 123 was chemically cleaned was classified into “large”, “medium”, and “small”.
Details of the above evaluation method will be described later.

  In the present specification, “chemical cleaning” means that the plasma-resistant member is chemically cleaned using a material that generates hydrogen ions in an aqueous solution. For example, hydrobromic acid, hydroiodic acid, hypochlorous acid, chlorous acid, chloric acid, perchloric acid, sulfuric acid, fluorosulfonic acid, nitric acid, hydrochloric acid, phosphoric acid, hexafluoroantimonic acid, tetrafluoroboric acid , Hexafluorophosphoric acid, chromic acid, boric acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, polystyrenesulfonic acid, acetic acid, citric acid, formic acid, gluconic acid, lactic acid And chemical cleaning using an aqueous solution containing at least one of oxalic acid, tartaric acid, hydrofluoric acid, carbonic acid and hydrogen sulfide. In this example, the chemical used for the evaluation was an acid solution such as hydrochloric acid or nitric acid, and the solution used for chemical cleaning during maintenance of the parts used in the semiconductor manufacturing equipment, including plasma-resistant parts, was selected. .

  The crystal structure of the yttria polycrystal in the layered structure 123 varies depending on the heat treatment conditions. As shown in FIG. 3, the ratios of monoclinic crystals to the cubic crystals of Samples 1 to 5 are 20% to 140%, 40% to 60%, 20% to 40%, 0% to 5%, respectively. % Or less, 0% or more and 2% or less. The crystallite sizes of Samples 1 to 5 are 7 nm to 19 nm, 8 nm to 20 nm, 12 nm to 25 nm, 20 nm to 35 nm, and 35 nm to 50 nm, respectively. The lattice strains of Samples 1 to 5 are 0.5% to 1.4%, 0.4% to 1.3%, 0.3% to 1.1%, 0.1% to 0, respectively. 0.7% or less, 0.0% or more and 0.6% or less. The atomic number concentration ratio of oxygen to yttrium in Samples 1 to 5 is 1.9% to 2.2%, 1.5% to 1.8%, 1.5% to 1.8%, It is 1.4% or more and 1.7% or less, and 1.3% or more and 1.6% or less.

  In addition, the inventor measured the interval between crystallites adjacent to each other in the yttria polycrystal of the layered structure 123. Here, the space | interval of adjacent crystallites is the space | interval which crystallites adjoined most, and does not include the space | gap comprised from a several crystallite.

The space | interval of crystallites can be calculated | required from the image obtained by observation using a transmission electron microscope (Transmission Electron Microscope: TEM).
FIG. 4 is a photograph illustrating the layered structure formed on the surface of the plasma-resistant member. In the example of FIG. 4, the yttria polycrystal of Sample 2 subjected to the heat treatment was observed after being thinned using a focused ion beam (FIB) method. In the observation, a transmission electron microscope (H-9000NAR / manufactured by Hitachi Technologies) was used, and the acceleration voltage was set to 300 kV. In the transmission electron microscope image, the gap G1 between the adjacent crystallites 125 in the yttria polycrystal was 0 nm or more and less than 10 nm. For example, the average value of the gap G1 in the observed image is 0 nm or more and less than 10 nm.

  The chemical resistance of the layered structure 123 varies depending on the crystal structure of the yttria polycrystal contained in the layered structure 123. For example, in sample 1 that was not subjected to heat treatment, the variation in surface roughness after chemical cleaning was “large”. On the other hand, in the samples 2 and 3 subjected to the heat treatment, the variation in the surface roughness after chemical cleaning is “medium” and the chemical resistance is high. In Samples 4 and 5, the variation in surface roughness after chemical cleaning is “small”, and the chemical resistance is high.

When the ratio of the monoclinic crystal to the cubic crystal is 0% or more and 60% or less, the chemical resistance can be improved and the chamber condition can be stably maintained.
Even when heat treatment is performed, the lattice strain of the yttria polycrystal contained in the layered structure 123 is 0% or more and 1.3% or less. Thereby, the crystallite size of the yttria polycrystal is as small as 8 nm or more and 50 nm or less. And the space | interval of the mutually adjacent crystallites is less than 10 nm, Preferably it is 5 nm or less. Thus, since the yttria polycrystal has a very dense structure, chemical resistance can be maintained and particles can be reduced.

It can also be seen that the chemical resistance is high when the ratio of the atomic concentration of oxygen to the atomic concentration of yttrium is 1.3 or more and 1.8 or less.
In the sample 1 not subjected to the heat treatment, the atomic number concentration ratio is 1.9 to 2.2. On the other hand, the atomic number concentration is lowered by the heat treatment. This is considered to be because, for example, dehydration bonds via OH groups were generated by the heat treatment. Thereby, yttria particles are bonded more firmly, a denser structure is obtained, and chemical resistance is improved.

  Here, X-ray diffraction (XRD) was used to measure the crystallite size, the ratio of monoclinic crystals to cubic crystals, and lattice distortion.

The Scherrer equation below was used to calculate the crystallite size.
D = Kλ / (βcosθ)
Here, D is the crystallite size, β is the peak half width (radian (rad)), θ is the Bragg angle (rad), and λ is the wavelength of the X-ray used for the measurement.
In the Scherrer equation, β is calculated by β = (β _obs −β _std ). β _obs is the half width of the X-ray diffraction peak of the measurement sample, and β _std is the half width of the X-ray diffraction peak of the standard sample. 0.94 was used as the value of K.

  The crystallite size may be calculated from an image such as TEM observation. For example, the average value of the equivalent circle diameters of the crystallites can be used as the crystallite size.

  For the calculation of the ratio of monoclinic crystals to cubic crystals, the strongest peak intensity attributed to cubic crystals near 2θ = 29 ° and the strongest peak intensity attributed to monoclinic crystals near 2θ = 30 ° were used. Note that the ratio of the monoclinic crystal to the cubic crystal may be calculated from the peak area ratio instead of the peak intensity ratio. That is, the ratio of monoclinic crystal to cubic crystal is as follows: monoclinic peak intensity (M) / cubic peak intensity (C) × 100 (%) or monoclinic peak area (M) / cubic crystal Of the peak area (C) × 100 (%).

For the calculation of the lattice distortion, the following Wilson equation was used using a peak in the vicinity of 2θ = 48 °.
d = β / (4 tan θ)
Here, d is a lattice distortion. β is a peak half width (rad), β is a peak half width (rad), and θ is a Bragg angle (rad). In the Wilson equation, β is calculated by β = (β _obs ² −β _std ² ) ^1/2 . β _obs is the half width of the X-ray diffraction peak of the measurement sample, and β _std is the half width of the X-ray diffraction peak of the standard sample.

  As the XRD apparatus, “X'PertPRO / Panalytical” was used. A tube voltage of 45 kV, a tube current of 40 mA, and a scan step of 0.017 ° were used.

  The ratio of the oxygen atom number concentration to the yttrium atom concentration (O / Y) is determined by quantitative analysis using energy dispersive X-ray spectroscopy (EDX). For example, by performing semi-quantitative analysis on oxygen and yttrium using SEM-EDX (SEM: S-3000N / manufactured by Hitachi High-Technologies, EDX: EMAX ENERGY / manufactured by Horiba Seisakusho), atomic number concentration ratio (O / Y) Can be calculated. As analysis conditions, acceleration voltage: 15 kV, X-ray extraction angle: 35 degrees (sample tilt angle: 0 degree), working distance (WD): 15 mm, magnification: 200 times, analysis area: 500 μm × 680 μm Can do.

The inventor found that the layer shape formed on the surface of the plasma-resistant member 120 by the arithmetic average Sa, the core volume Vmc, the core hollow volume Vvc, the developed area ratio Sdr of the interface, and the root mean square slope SΔq. It was determined that the surface state of the structure 123 can be expressed and evaluated in a form that covers the entire surface of the layered structure 123. Therefore, the arithmetic average Sa was used to evaluate the variation in the surface roughness of the layered structure 123 formed on the surface of the plasma-resistant member 120 after chemical cleaning. In addition, for the evaluation of the variation in the surface roughness of the layered structure, the arithmetic average roughness Ra may be used instead of the arithmetic average Sa. The arithmetic average roughness Ra can be measured using, for example, a stylus type surface roughness meter.
FIG. 5 is a schematic diagram for explaining the three-dimensional surface property parameter. FIG. 5A is a graph illustrating the amplitude average (arithmetic average) Sa in the height direction. FIG. 5B is a graph illustrating the substantial volume Vmc of the core part and the hollow volume Vvc of the core part. FIG. 5C is a schematic plan view for explaining the density of protrusions (or holes) in the defined segmentation.

  The inventor examined the surface state of the layered structure using a laser microscope. As the laser microscope, “OLS4000 / manufactured by Olympus” was used. The magnification of the objective lens is 100 times. The zoom is 5 times. The cut-off was set to 2.5 μm or 0.8 μm.

  The amplitude average (arithmetic average) Sa in the height direction is obtained by extending the two-dimensional arithmetic average roughness Ra to three dimensions, and is a three-dimensional roughness parameter (three-dimensional height direction parameter). Specifically, the arithmetic average Sa is obtained by dividing the volume of the portion surrounded by the surface shape curved surface and the average surface by the measurement area. When the average plane is the xy plane, the vertical direction is the z-axis, and the measured surface shape curve is z (x, y), the arithmetic mean Sa is defined by the following equation. Here, “A” in the formula (1) is a measurement area.

Parameters relating to the substantial volume Vmc of the core portion and the hollow volume Vvc of the core portion obtained from the load curve are defined as a graph shown in FIG. 5B, and are three-dimensional volume parameters. That is, the height when the load area ratio is 10% is a boundary between the substantial volume Vmp of the mountain part, the substantial volume Vmc of the core part, and the hollow volume Vvc of the core part. The height when the load area ratio is 80% is a boundary between the hollow volume Vvv of the valley part, the substantial volume Vmc of the core part, and the hollow volume Vvc of the core part. The substantial volume Vmp of the peak part, the substantial volume Vmc of the core part, the hollow volume Vvc of the core part, and the hollow volume Vvv of the valley part represent a volume per unit area (unit: m ³ / m ² ).

  The developed area ratio Sdr of the interface is a parameter indicating the increase rate of the interface with respect to the sampling surface. The developed area ratio Sdr of the interface is a value obtained by dividing the total developed area of the small interfaces formed by four points by the measured area, and is defined by the following equation. Here, “A” in Equation (2) represents the defined segmentation area.

The root mean square slope SΔq represents a two-dimensional mean square slope angle Δq on the sampling surface. At every point, the surface slope is expressed as:

Therefore, the root mean square slope SΔq is expressed by the following equation.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. As long as the features of the present invention are provided, those skilled in the art appropriately modified the design of the above-described embodiments are also included in the scope of the present invention. For example, the shape, size, material, arrangement, etc. of each element included in the semiconductor manufacturing apparatus 100 and the like, and the installation form of the plasma resistant member 120 and the electrostatic chuck 160 are not limited to those illustrated, but may be changed as appropriate. be able to.
Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

  100 Semiconductor Manufacturing Equipment, 110 Chamber, 120 Plasma Resistant Member, 123 Layered Structure, 125 Crystallite, 160 Electrostatic Chuck, 191 Region, 210 Wafer, 221 Particles

Claims (5)

A substrate;
A layered structure including a yttria polycrystal formed on the surface of the substrate by an aerosol deposition method and having plasma resistance;
With
The yttria polycrystal constituting the layered structure has a crystal structure in which cubic and monoclinic crystals are mixed,
In the yttria polycrystals constituting the layered structure, the ratio of monoclinic crystals to cubic crystals is 0% or more and 60% or less,
The yttria polycrystal constituting the layered structure has a crystallite size of 8 nm to 50 nm.   2. The plasma-resistant member according to claim 1, wherein an interval between crystallites adjacent to each other in the yttria polycrystal constituting the layered structure is 0 nm or more and less than 10 nm.   The ratio (O / Y) of the atomic number concentration of oxygen (O) to the atomic concentration of yttrium (Y) in the yttria polycrystal constituting the layered structure is 1.3 or more and 1.8 or less. The plasma-resistant member according to claim 1 or 2.   4. The plasma-resistant member according to claim 1, wherein the yttria polycrystal constituting the layered structure has a lattice strain of 0% or more and 1.3% or less.   The said layered structure is formed by heat-processing, The plasma-resistant member as described in any one of Claims 1-4 characterized by the above-mentioned.