JP2020012192A - Composite structure, semiconductor manufacturing equipment including composite structure, and display manufacturing apparatus - Google Patents

Abstract

To provide a ceramic coat excellent in particle resistance; and to provide a method for evaluating particle resistance of the ceramic coat.SOLUTION: A composite structure includes a substrate, and a structure provided on the substrate, and having a surface. The composite structure in which the structure includes a polycrystalline ceramic, and brightness Sa calculated from its TEM image analysis satisfies a prescribed value, can be used suitably as an internal member of semiconductor manufacturing equipment requiring particle resistance.SELECTED DRAWING: None

Description

  The present invention relates to a composite structure in which a substrate is provided with a function by coating the surface of the substrate with polycrystalline ceramic. The present invention also relates to a semiconductor manufacturing device and a display manufacturing device provided with the composite structure. In particular, the present invention relates to a composite structure excellent in particle resistance (low-particle generation) used in an environment exposed to corrosive plasma, such as a member of a semiconductor manufacturing apparatus, a semiconductor manufacturing apparatus having the composite structure, and The present invention relates to a display manufacturing device.

  2. Description of the Related Art There is known a technique in which a ceramic is coated on the surface of a base material to impart a function to the base material. For example, as such a ceramic coat, a plasma-resistant coat of a chamber constituent member in a semiconductor manufacturing apparatus or the like, an insulative coat in a heat dissipation base or the like, an ultra-smooth coat in an optical mirror or the like, a scratch-resistant and abrasion resistant in a sliding member or the like There is a nature coat and the like. The demand level has become higher with the enhancement of the functions of such members, and in these ceramic coats, it is not only the material composition that governs the performance but also the physical structure, It may be especially microstructured.

  As a technique for obtaining such a ceramic coat, an aerosol deposition method (AD method), a PVD (Physical Vapor Deposition) method (PEPVD (Plasma-Enhanced Physical Vapor Deposition) method) in which a film is thickened by plasma or ion assist. Various types of ceramic coating techniques, such as an IAD (Ion Assisted Deposition) method and a suspension spraying method using a suspension (suspension) of a fine raw material, have been developed.

  Ceramic coats carefully manufactured by these methods also have some control over the microstructure. In previous reports, the porosity confirmed by an image analysis method such as a scanning electron microscope (SEM) is 0.01 to 0.1%.

  For example, Japanese Patent Application Laid-Open No. 2005-217351 (Patent Document 1) discloses, as a member for a semiconductor manufacturing apparatus having plasma resistance, a layered structure made of a polycrystalline yttria having a pore occupancy of 0.05 area% or less. I do. This layered structure is said to have suitable plasma resistance.

Also, Korean Patent No. 2017778830A (Patent Document 2) discloses a YF ₃ transparent fluorine-based thin film having high resistance to plasma and corrosive gas. It is said that the YF ₃ thin film has a high porosity of 0.01-0.1% and thus has high resistance to plasma and the like. The withstand voltage is set to 50 to 150 V / μm.

Japanese Patent Application Publication No. 2006-511796 (Patent Document 3) discloses a ceramic coating such as Y ₂ O ₃ containing constituent particles having a particle size of 200 to 900 nm and constituent particles having a particle size of 900 nm to 10 μm. . This coating is said to be dense with a porosity of 0.01-0.1% and high in resistance to plasma and the like. The withstand voltage is set to 80 to 120 V / μm.

  The Chemical Society of Japan 1979, (8), p. 1106 to 1108 (Non-Patent Document 1) disclose a refractive index and a reflectance as optical characteristics of a yttrium oxide sintered body that is a transparent plate-shaped sample (see FIG. 10).

  In the field of semiconductor manufacturing equipment, miniaturization of semiconductor devices is progressing year by year, and it is estimated that if EUV (Extreme ultraviolet lithography) is put into practical use, it will reach several nm. According to IRDS (International Roadmap for Devices and Systems) and MORE MOORE WHITE PAPER 2016 EDITION prepared by IEEE (The Institute of Electrical and Electronics Engineers, Inc), the half pitch in the horizontal direction between devices in 2017 is 18.0 nm. , 2019, it is predicted to decrease to 12.0 nm, and from 2021 onwards, it will decrease to 10.0 nm or less.

For the purpose of high integration of such semiconductors, the circuit line width and the circuit pitch are further reduced. Further, for example, in the etching step, a corrosive plasma such as a fluorine-based plasma such as CF ₄ or NF ₃ or a chlorine-based plasma is used. In the future, processing using high-density plasma will be performed more than ever, and various members in a semiconductor manufacturing apparatus are required to have a higher level of particle resistance.

  Conventionally, the plasma resistance of a ceramic coat correlates with its porosity, and the generation of particles can be suppressed by suppressing the consumption itself of the ceramic coat due to plasma erosion. The problem of particles has been solved by reducing the size to 01 to 0.1%. However, according to the knowledge obtained by the present inventors, it has become impossible to solve the problem of suppressing the generation of particles even with a structure having an extremely small porosity while further miniaturization proceeds. That is, they came to the understanding that not only the consumption of the ceramic coat using the porosity as an index but also the generation of particles from another viewpoint must be controlled with higher precision.

  That is, in recent years of device miniaturization and high-density plasma, even with a ceramic structure having a porosity of 0.01 to 0.1% and containing almost no pores, the particle problem still exists. Therefore, a structure having further particle resistance is required. Further, there is a demand for a ceramic structure that can solve the particle problem even in a fine device having a line width of several nanometers in a semiconductor circuit in the future.

JP 2005-217351 A Korean patent 20170778030A JP 2006-511796 A

The Chemical Society of Japan 1979, (8), p. 1106 to 1108 “Refractive index and reflectance of yttrium oxide sintered body”

  The present inventors have recently succeeded in obtaining a composite structure capable of extremely reducing the influence of particles in a ceramic coat used in a situation exposed to a corrosive plasma environment such as a semiconductor manufacturing apparatus. . Then, it was found that some indices have a high correlation with the particle resistance performance at an extremely high level, and thereafter, these indices, specifically defined by indices according to the first to fifth aspects described later. Successfully created a structure with excellent particle resistance.

  Therefore, the present invention solves the problem of providing a composite structure having a polycrystalline ceramic structure with a controlled microstructure, and in particular, suppressing the generation of particles even in highly miniaturized and high-density plasma. It is an object to provide a composite structure comprising a possible polycrystalline ceramic structure on a substrate.

  Another object of the present invention is to provide a semiconductor manufacturing apparatus and a display manufacturing apparatus provided with the composite structure.

1 is a schematic cross-sectional view of a composite structure 100 according to the present invention. 5 is a flowchart illustrating a method for evaluating luminance Sa according to the present invention. FIG. 3 is a schematic diagram of a TEM observation sample 90. FIG. 2 is a schematic diagram showing a TEM image G of a structure 10. It is a figure which shows the TEM image G and the brightness value for every pixel. FIG. 4 is a diagram illustrating a luminance correction of a TEM image G. FIG. 6 is a diagram illustrating a luminance value in a luminance acquisition region R. It is a schematic diagram which shows the example at the time of using the composite structure 100 as the semiconductor manufacturing apparatus member 301. It is a schematic diagram which shows the example at the time of using the composite structure 100 as the semiconductor manufacturing apparatus member 302. It is a schematic diagram which shows an example of the apparatus structure used for an aerosol deposition method. 4 is a TEM image of the structure 10 at a magnification of 400,000. It is a scanning electron microscope (SEM) image of the structure 10. 6 is a transmission electron microscope image (TEM) image G of the structure 10. It is a scanning electron microscope (SEM) image of the structure 10 surface after a reference plasma resistance test. It is a graph which shows the corrosion trace area of the structure 10 after a reference | standard plasma resistance test. 4 is a graph showing a relationship between luminance Sa on a surface 10a of a structure 10 and an area of a corrosion mark. 4 is a graph showing the relationship between the amount of hydrogen on the surface 10a of the structure 10 and the area of the corrosion trace. It is a typical sectional view for explaining the microstructure of a composite structure. 4 is a graph showing a relationship between a wavelength of a structure 10 and a refractive index. 4 is a graph showing the wavelength dispersion of the refractive index of a yttrium oxide sintered body according to the related art.

Composite Structure The basic structure of the composite structure according to the present invention will be described with reference to FIG. FIG. 1 is a schematic sectional view of a composite structure 100 according to the present invention. The structure 10 is provided on the surface 70 a of the base 70. This structure 10 has a surface 10a. The surface 10a is a surface that is exposed to the environment in an environment where the physical properties and characteristics imparted by the structure 10 to the composite structure are required. Therefore, for example, in the case where the composite structure according to the present invention is a composite structure in which the physical properties and characteristics of particle resistance are provided by the structure 10, the surface 10 of the composite structure is exposed to corrosive gas such as plasma. The exposed surface. In the present invention, the structure 10 includes a polycrystalline ceramic. Furthermore, the structure 10 included in the composite structure according to the present invention shows a predetermined value in the index in the first to fifth aspects described later.

  The structure 10 provided in the composite structure according to the present invention is a so-called ceramic coat. By applying the ceramic coat, various physical properties and characteristics can be imparted to the substrate 70. In this specification, a structure (or a ceramic structure) and a ceramic coat are used synonymously unless otherwise specified.

  According to one aspect of the present invention, structure 10 is based on polycrystalline ceramics. The content of the polycrystalline ceramic is 70% or more, preferably 90% or more, and more preferably 95% or more. Most preferably, the structure 10 is made of 100% polycrystalline ceramic.

  In addition, according to one embodiment of the present invention, the structure 10 may include a polycrystalline region and an amorphous region, but it is more preferable that the structure 10 be composed of only polycrystal.

Method for Measuring Crystallite Size In the present invention, the size of the polycrystalline ceramic constituting the structure 10 is 3 nm or more and 50 nm or less as an average crystallite size obtained under the following measurement conditions. More preferably, the upper limit is 30 nm, more preferably 20 nm, even more preferably 15 nm. The preferred lower limit is 5 nm. The “average crystallite size” in the present invention is obtained by taking a transmission electron microscope (TEM) image at a magnification of 400,000 times or more, and calculating an average diameter of 15 crystallites in this image by circular approximation. This is a calculated value. At this time, the sample thickness at the time of processing a focused ion beam (FIB) is sufficiently reduced to about 30 nm. Thereby, the crystallite can be distinguished more clearly. The photographing magnification can be appropriately selected within a range of 400,000 times or more. FIG. 11 is an example of a TEM image for crystallite size measurement. Specifically, FIG. 11 is a TEM image of the structure 10 at a magnification of 2,000,000. In the figure, the region indicated by 10c is a crystallite.

  As described above, the ceramics constituting the structure 10 may be appropriately determined according to the physical properties and characteristics desired to be imparted to the base material 70, and include a metal oxide, a metal fluoride, a metal nitride, a metal carbide, or a mixture thereof. May be. According to one embodiment of the present invention, as a compound having excellent particle resistance, an oxide of a rare earth element, a fluoride, an oxyfluoride (LnOF), or a mixture thereof is given as a material. More specifically, the rare earth element Ln includes Y, Sc, Yb, Ce, Pr, Eu, La, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu.

Further, in the case of the structure 10 of the insulating _property, it can be used _{Al 2 O 3, ZrO 2,} AlN, SiC, Si 3 N 4, cordierite, forsterite, mullite, silica, a material such as.

  In the present invention, the film thickness of the structure 10 may be appropriately determined in consideration of the required use, characteristics, film strength, and the like. Generally, it is in the range of 0.1 to 50 μm, and the upper limit may be, for example, 20 μm, 10 μm, or 5 μm, or even 1 μm or less. Here, the film thickness of the structure 10 can be confirmed, for example, by cutting the structure 10 and observing the fractured surface by SEM observation.

  In the present invention, the base material 70 is an object to which a function is provided by the structure 10 and may be appropriately determined. Examples of the material include ceramics, metals, resins, and the like, and a composite thereof may be used. Examples of the composite include a composite substrate of resin and ceramic, a composite substrate of fiber-reinforced plastic and ceramic, and the like. The shape is not particularly limited, and may be a flat plate, a concave surface, a convex surface, or the like.

  According to one embodiment of the present invention, it is preferable that the surface 70 a of the base material 70 to be bonded to the structure 10 be smooth for the formation of a good structure 10. According to one embodiment of the present invention, the surface 70a of the substrate 70 is subjected to at least one of blasting, physical polishing, chemical mechanical polishing, lapping, and chemical polishing to remove irregularities on the surface 70a. I do. In such unevenness removal, the surface 70a thereafter has, for example, a two-dimensional arithmetic average roughness Ra of 0.2 μm or less, more preferably 0.1 μm or less, or a two-dimensional arithmetic average height Rz of 3 μm or less. It is preferable to be performed as follows.

  The composite structure according to the present invention can be suitably used as various members in a semiconductor manufacturing apparatus, particularly, a member used in an environment exposed to a corrosive plasma atmosphere. The members inside the semiconductor manufacturing apparatus are required to have particle resistance as described above. This is because the structure including the polycrystalline ceramic included in the composite structure according to the present invention has high particle resistance.

When the composite structure according to the present invention is used as a member used in an environment exposed to a corrosive plasma atmosphere, the composition of the ceramic constituting the structure 10 may be Y ₂ O ₃ , yttrium oxyfluoride (YOF, YF). ₅ O ₄ F ₇ , Y ₆ O ₅ F ₈ , Y ₇ O ₆ F ₉ and Y ₁₇ O ₁₄ F ₂₃ ), (YO _0.826 F _0.17 ) F _1.174 , YF ₃ , Er ₂ O _{3 , Gd 2 O 3, Nd 2} O 3, Y 3 Al 5 O 12, Y 4 Al 2 O 9, Er 3 Al 5 O 12, Gd 3 Al 5 O 12, Er 4 Al 2 O 9, ErAlO 3, Gd ₄ Al ₂ O ₉ , GdAlO ₃ , Nd ₃ Al ₅ O ₁₂ , Nd ₄ Al ₂ O ₉ , NdAlO ₃ , and the like.

Plasma Resistance The composite structure according to the present invention, which is defined by indices according to the first to fifth aspects described later, has plasma resistance. The plasma resistance can be evaluated using a plasma resistance test described below as one reference method. Hereinafter, in this specification, this plasma resistance test is referred to as a “reference plasma resistance test”.

  As one embodiment of the present invention, a composite structure in which the arithmetic mean height Sa of the surface 10a of the structure 10 after the “reference plasma resistance test” is 0.060 or less is preferable, and more preferably 0.030 or less. Things. The arithmetic mean height Sa will be described later.

An inductively coupled plasma reactive ion etching apparatus (Muc-21 Rv-Aps-Se / Sumitomo Seimitsu Kogyo) is used as a plasma etching apparatus for the "reference plasma resistance test". The plasma etching conditions were as follows: power supply output: ICP (Inductively Coupled Plasma) output: 1500 W; bias output: 750 W; process gas: a mixed gas of CHF ₃ gas 100 ccm and O ₂ gas 10 ccm; The plasma etching time is one hour.

  The state of the surface 10a of the structure 10 after the plasma irradiation is photographed by a laser microscope (for example, OLS4500 / Olympus). Details such as observation conditions will be described later.

The arithmetic mean height Sa of the surface after plasma irradiation is calculated from the obtained SEM image. Here, the arithmetic mean height Sa is obtained by expanding the two-dimensional arithmetic mean roughness Ra into three dimensions, and is a three-dimensional roughness parameter (three-dimensional height direction parameter). Specifically, the arithmetic average height Sa is obtained by dividing the volume of the portion surrounded by the surface shape curved surface and the average surface by the measured area. That is, assuming that 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 average height Sa is defined by the following equation. Here, “A” in Expression (1) is a measurement area.

  The arithmetic mean height Sa is a value that does not basically depend on the measurement method, but is calculated under the following conditions in the “reference plasma resistance test” in this specification. A laser microscope is used to calculate the arithmetic mean height Sa. Specifically, a laser microscope “OLS4500 / Olympus” is used. The objective lens uses MPLAPON 100 × LEXT (numerical aperture 0.95, working distance 0.35 mm, focused spot diameter 0.52 μm, measurement area 128 × 128 μm), and the magnification is 100 times. The λc filter for removing the undulation component is set to 25 μm. The measurement is performed at any three places, and the average value is defined as the arithmetic average height Sa. In addition, the three-dimensional surface texture international standard ISO25178 is appropriately referred to.

First Aspect of the Present Invention As a basis for the first aspect of the present invention, the present inventors include polycrystalline ceramics used in a situation exposed to a corrosive plasma environment such as a semiconductor manufacturing apparatus. In a composite structure having a structure, the influence of particles has been extremely reduced. Further, it has been found that particle resistance performance can be evaluated at an extremely high level by using an amount of hydrogen contained in a structure, which is measured by a secondary ion mass spectrometry (Dynamic-Secondary Ion Mass Spectrometry_D-SIMS method), as an index. Was.

The composite structure according to the first aspect of the present invention is a composite structure including a substrate and a structure provided on the substrate and having a surface, wherein the structure includes polycrystalline ceramics, The number of hydrogen atoms per unit volume at a measurement depth of 500 nm or 2 μm measured by secondary ion mass spectrometry (Dynamic-Secondary Ion Mass Spectrometry_D-SIMS method) is 7 * 10 ²¹ atoms / cm ^3. It is the following.

  FIG. 18 is a schematic cross-sectional view for describing the microstructure of the composite structure. 18A shows a conventional composite structure 110, and FIG. 18B shows a composite structure 100 according to the present invention. In the figure, 80 indicates a nano-level crude structure, and 90 indicates a water molecule (OH group). In FIG. 18, the size of the nano-level coarse structure 80 is increased for easy understanding. However, actually, both the composite structures 100 and 110 have a porosity according to a conventional evaluation method using an SEM or the like. Is 0.01 to 0.1%.

  The present inventors have focused on the fact that even with a structure having a low porosity of 0.01 to 0.1%, the particle problem still cannot be solved, and a novel problem that can solve the particle problem at a higher level is considered. The structure was successfully obtained. The reason why the particle problem cannot be solved by the conventional structure is that there is a nano-level coarse / dense variation as a fine structure in the structure, and it is considered that the plasma resistance of the rough structure 80 is lower than that of the dense structure. Then, for example, it is considered that water molecules (OH groups) contained in the atmosphere are present in the nano-level and slightly rough structure 80, and by performing this determination, a correlation with the particle resistance can be obtained. Thought. In other words, it has been found that by quantifying the amount of hydrogen in the water molecule (OH group), it is possible to specify the configuration of a novel structure that can solve the particle problem at a higher level.

  Specifically, in FIG. 18, it is considered that the composite structure 100 of the present invention has fewer coarse structures 80 and less water molecules (OH groups) existing in the coarse structure 80 than the conventional composite structure 110. Can be By quantifying the amount of hydrogen (the number of hydrogen atoms per unit volume) of the structure 10 by the secondary ion mass spectrometry (D-SIMS method) described later, it is possible to correlate with the particle resistance.

Preparation of Sample for Measurement of Hydrogen Amount in First Embodiment of the Present Invention In the first embodiment of the present invention, a sample for measurement of hydrogen amount can be prepared, for example, by the following method.

  First, a composite structure having the structure 10 is cut out in advance by a dicing machine or the like. At this time, a portion corresponding to the sample acquisition location 40 in FIGS. 8 and 9 is cut out. The size may be arbitrary, but is, for example, about 3 mm × 3 mm to 7 mm × 7 mm and a thickness of about 3 mm. The thickness of the sample may be appropriately determined according to the measuring device to be used or the like, and is adjusted by shaving the surface of the base material 70 on which the structure 10 is not formed. Arithmetic average roughness Ra, which is a parameter of two-dimensional surface roughness, is set to 0.1 μm or less, more preferably 0.01 μm, on the surface 10 a of the structure 10 by polishing or the like. The thickness of the structure 10 is at least 500 nm or more, preferably 1 μm or more, more preferably 3 μm or more.

  In the D-SIMS method, which is a method for measuring the amount of hydrogen in the present invention, measurement is generally performed using a standard sample. It is desirable to use a standard sample having the same composition and structure as the sample to be measured. For example, at least two samples can be prepared, and one of them can be used as a standard sample. Details of the standard sample will be described later.

  The state of the sample before the measurement of the amount of hydrogen will be described.

  As described above, in the present invention, the amount of hydrogen is used in the method of specifying the nano-level coarse structure of the structure 100. For this reason, it is important to manage the sample before the hydrogen amount measurement in a constant temperature and humidity chamber for a predetermined time. Specifically, in the present invention, the amount of hydrogen is measured after the sample has been left at room temperature of 20 to 25 ° C., humidity of 60% ± 10% and atmospheric pressure for 24 hours or more.

Measurement of hydrogen amount in the first aspect of the present invention will now be described a method for measuring the amount of hydrogen in the first aspect of the present invention.

  In the present invention, the amount of hydrogen is measured by a secondary ion mass spectrometry: D-SIMS (Dynamic-Secondary Ion Mass Spectrometry). As the device, for example, IME-7f manufactured by CAMECA is used.

  Next, measurement conditions will be described.

  First, conductive platinum (Pt) is deposited on the surface of the structure. As measurement conditions, cesium (Cs) ions are used as primary ion species. The primary acceleration voltage is 15.0 kV, and the detection area is 8 μmφ. The measurement depth is 500 nm and 2 μm.

  Particle resistance is highly dependent on the nature of the structure surface exposed directly to the plasma atmosphere. Therefore, by quantifying the amount of hydrogen in at least a region of about 500 nm in depth from the surface of the structure, the amount of hydrogen and the particle resistance can be effectively linked. On the other hand, if the thickness of the structure is sufficiently large and the microstructure from the surface to the depth to be measured is substantially homogeneous, the reliability of the quantitative results can be improved by measuring the area up to about 2 μm. Can be enhanced. The structure 10 has a lower region 10b on the side of the base material 70 and an upper region 10u on the surface 10a side (see FIG. 1). The particle resistance of the structure 10 is, for example, higher than that of the lower region 10b in the upper region 10u. In the case of a laminated structure that also increases the measurement depth, it is preferable to set the measurement depth so that the amount of hydrogen in only the upper region 10u can be determined. From this viewpoint, the hydrogen amount may be any of the hydrogen amounts defined in the present invention at either the measurement depth of 500 nm or 2 μm. Preferably, the hydrogen content of the present invention is satisfied at both the measurement depth of 500 nm and 2 μm.

  For the measurement of the amount of hydrogen, a measurement sample and a standard sample are prepared.

  The standard sample is generally used in the SIMS method to normalize the signal intensity of the ion species to be analyzed with the signal intensity of the ion species including the matrix element of the sample for the purpose of canceling out the factors relating to the measurement conditions. More specifically, an evaluation sample, a standard sample for an evaluation sample having a matrix component equivalent to the evaluation sample, an Si single crystal, and a standard sample for a Si single crystal are used. The standard sample for the evaluation sample is obtained by injecting deuterium into a sample having a matrix component equivalent to that of the evaluation sample. At this time, it is assumed that deuterium is simultaneously injected into the Si single crystal, and that equivalent deuterium is injected into the standard sample for the evaluation sample and the Si single crystal. Thereafter, the amount of deuterium injected into the Si single crystal is identified using a standard sample for the Si single crystal. For the standard sample for the evaluation sample, the secondary ion intensities of deuterium and constituent elements are calculated using secondary ion mass spectrometry (D-SIMS method), and the interphase sensitivity coefficient is calculated. The amount of hydrogen in the evaluation sample is calculated using the inter-phase sensitivity coefficient calculated from the standard sample for the evaluation sample. For others, reference can be made to ISO 18114_ “Determining relative sensitivity factors from ion-implanted reference materials” (International Organization for Standardization, Geneva, 2003).

In the present invention, a secondary ion mass spectrometry (Dynamic-Secondary Ion Mass Spectrometry_D-SIMS method) included in a structure constituting a composite structure, at a measurement depth of 500 nm or 2 μm or less. The number of hydrogen atoms per unit volume is 7 * 10 ²¹ atoms / cm ³ or less.

  In the structure of the present invention, the surface is directly exposed to, for example, a plasma atmosphere. Therefore, the properties of the structure surface are particularly important. The present inventors have considered that even a structure having a porosity of 0.01 to 0.1% and containing almost no porosity, the particle problem has not been able to be solved due to the influence of the nano-level microstructure. As a result, we succeeded in controlling this nano-level microstructure and obtained a novel structure that can solve the particle problem at a higher level. In addition, they have newly found that the configuration of this novel structure can be specified using the amount of hydrogen on the surface (the number of hydrogen atoms per unit volume) as an index. The inventors have found a correlation between the amount of hydrogen on the surface of the structure and the particle resistance, and have reached the present invention.

  Specifically, for example, in the atmosphere, a hydrogen atom is considered to exist in a state of, for example, a hydroxyl group (—OH). The size of the molecule is about 3% for a water molecule and about 1% for a hydroxyl group, and it is considered that the molecule slightly exists in the above-described crude structure 80 or the like. By using this hydrogen amount as an index, a nano-level microstructure can be represented.

In the present invention, the number of hydrogen atoms per unit volume at a measurement depth of 500 nm or 2 μm, measured by D-SIMS, is 7 * 10 ²¹ atoms / cm ³ or less as the hydrogen amount of the structure. The number of hydrogen atoms per unit volume is preferably 5 * 10 ²¹ atoms / cm ³ or less.

  It is considered that the smaller the amount of hydrogen in the structure of the composite structure according to the present invention, the better, but it is apparent to those skilled in the art that a practical measurement limit also exists. Therefore, the lower limit of the amount of hydrogen in this embodiment is the measurement limit. This point is the same in the following second embodiment.

Second Embodiment of the Present Invention In the second embodiment of the present invention, as in the first embodiment of the present invention, the amount of hydrogen is used as an index, but hydrogen forward scattering analysis (HFS) -Rutherford backscattering spectroscopy. The amount of hydrogen measured by the method (RBS) (RBS-HFS method) and the proton-hydrogen forward scattering analysis method (p-RBS method) is used as an index. That is, the present inventors have developed a composite structure including a structure containing Y (yttrium element) and O (oxygen element) used in a situation exposed to a corrosive plasma environment such as a semiconductor manufacturing apparatus. We succeeded in minimizing the effects of particles. The hydrogen contained in the structure is measured by hydrogen forward scattering analysis (HFS) -Rutherford backscattering spectroscopy (RBS) (RBS-HFS method) and proton-hydrogen forward scattering analysis method (p-RBS method). By using the amount as an index, it has been found that particle resistance performance can be evaluated at an extremely high level.

  The composite structure according to the second aspect of the present invention is a composite structure including a substrate and a structure provided on the substrate and having a surface, wherein the structure includes polycrystalline ceramics, Hydrogen forward scattering analysis (HFS)-Rutherford backscattering spectroscopy (RBS) (RBS-HFS method) and proton-hydrogen forward scattering analysis (p-RBS method) when the hydrogen atom concentration is 7 atomic% or less. There is something.

  The second embodiment of the present invention is different from the first embodiment of the present invention in the method for measuring the amount of hydrogen, and the description of the first embodiment in the present specification, except for a case where a change due to the difference is added. Is an explanation of the second invention.

Preparation of Sample for Measuring Hydrogen Content in Second Embodiment of the Present Invention In the second embodiment of the present invention, a sample for measuring hydrogen content can be prepared, for example, by the following method.

  First, a composite structure having the structure 10 is cut out in advance by a dicing machine or the like. At this time, a portion corresponding to the sample acquisition location 40 in FIGS. 8 and 9 is cut out. The size may be arbitrary, but is, for example, about 20 mm × 20 mm and about 5 mm in thickness. In addition, the thickness of the sample may be appropriately determined according to a measuring device to be used or the like, and is adjusted by, for example, shaving the surface of the base material 70 on which the structure 10 is not formed. Arithmetic average roughness Ra, which is a parameter of two-dimensional surface roughness, is set to 0.1 μm or less, more preferably 0.01 μm, on the surface 10 a of the structure 10 by polishing or the like. The thickness of the structure 10 is at least 500 nm or more, preferably 1 μm or more, more preferably 3 μm or more.

  The state of the sample before the measurement of the amount of hydrogen will be described.

  As described above, in the present invention, the amount of hydrogen is used in the method of specifying the nano-level coarse structure of the structure 100. For this reason, it is important to manage the sample before the hydrogen amount measurement in a constant temperature and humidity chamber for a predetermined time. Specifically, in the present invention, the amount of hydrogen is measured after the sample has been left at room temperature of 20 to 25 ° C., humidity of 60% ± 10% and atmospheric pressure for 24 hours or more.

Next, a method for measuring the amount of hydrogen in the second embodiment of the present invention will be described.

  In the present invention, the amount of hydrogen is measured by a Hydrogen Forward scattering Spectrometry (HFS) / Rutherford Backscattering Spectrometry (RBS) method (hereinafter referred to as an RBS-HFS method), and a proton (hereinafter referred to as a proton method). -Referred to as RBS). As the device, for example, Pelletron 3SDH manufactured by National Electrostatics Corporation can be used.

  The method for quantifying the amount of hydrogen will be further described.

  An RBS-HFS method using a helium (He) element is performed. The structure is irradiated with helium (He atoms) to detect back-scattered He atoms and forward-scattered H atoms. For the energy spectrum of the back-scattered He atom, fitting is performed in order from the element having the largest energy spectrum, and the scattering intensity is calculated. In addition, the energy spectrum of the forward-scattered H atom is also fitted, and the scattering intensity is calculated. calculate. The ratio of the average number of atoms of the elements in the structure can be calculated based on the calculated scattering intensities. For example, when the structure is yttrium oxide, the energy spectrum of the detected He atom performs fitting for the Y element and calculates the scattering intensity, and then performs fitting for the O element to calculate the scattering intensity. I do. Note that it is preferable to combine other methods such as an energy dispersive X-ray analysis (EDX) method to specify the element having the largest energy spectrum.

According to the above RBS-HFS method, the ratio of the average number of atoms of the elements in the structure in the structure is measured. In order to improve the measurement accuracy, in the present invention, p-type using proton (H ⁺ ) is further used in the present invention. The ratio of the average number of atoms other than hydrogen in the structure is measured again by the RBS method. At the time of calculation, fitting is performed in order from the element having the largest energy spectrum measured in the same manner as in the RBS-HFS method, and the scattering intensity is calculated. The ratio of the average number of atoms of the elements in the structure is calculated based on the calculated scattering intensities. Then, the element having the largest ratio of the average number of atoms measured by the p-RBS method and the energy spectrum of the detected He atom measured by the RBS-HFS method (for example, if the structure is yttrium oxide, the element is detected. The amount of hydrogen is calculated as the concentration of hydrogen atoms (atomic%) by combining the element having the largest energy spectrum of He atoms (Y) and the ratio of the average number of hydrogen atoms.

  In the present invention, the order of performing the p-RBS method and the RBS-HFS method is not particularly limited.

  Next, measurement conditions will be described.

4He ⁺ is used for the RBS-HFS method incident ions. The incident energy is 2300 KeV, the incident angle is 75 °, the scattering angle is 160 °, and the recoil angle is 30 °. The sample current is 2 nA, the beam diameter is 1.5 mmφ, and the irradiation amount is 8 μC. There is no in-plane rotation.

Hydrogen ions (H ⁺ ) are used as incident ions for the p-RBS method . The incident energy is 1740 KeV, the incident angle is 0 °, the scattering angle is 160 °, and there is no recoil angle. The sample current is 1 nA, the beam diameter is 3 mmφ, and the irradiation amount is 19 μC. There is no in-plane rotation.

  By combining the p-RBS method in addition to the RBS-HFS method, the measurement accuracy of the hydrogen atom concentration can be further improved, and the amount of hydrogen (hydrogen atom concentration) can be quantified in association with particles.

  The concentration of hydrogen atoms contained in the structure constituting the composite structure of the present invention is 7 atom% or less. In the structure of the present invention, its surface is directly exposed to, for example, a plasma atmosphere. Therefore, the properties of the structure surface are particularly important. The present inventors have considered that even a structure having a porosity of 0.01 to 0.1% and containing almost no porosity, the particle problem has not been able to be solved due to the influence of the nano-level microstructure. As a result, we succeeded in controlling this nano-level microstructure and obtained a novel structure that can solve the particle problem at a higher level. In addition, they have newly found that the structure of this novel structure can be specified using the amount of hydrogen (hydrogen atom concentration) on the surface as an index. The inventors have found a correlation between the amount of hydrogen on the surface of the structure and the particle resistance, and have reached the present invention.

  Specifically, for example, in the atmosphere, a hydrogen atom is considered to exist in a state of, for example, a hydroxyl group (—OH). The size of the molecule is about 3% for a water molecule and about 1% for a hydroxyl group, and it is considered that the molecule slightly exists in the above-described crude structure 80 or the like. By using this hydrogen amount (hydrogen atom concentration) as an index, a nano-level microstructure can be represented.

  In the present invention, as a method for specifying the amount of hydrogen, a method combining the p-RBS method and the RBS-HFS method is used. In these methods, helium ions or hydrogen ions are incident on the sample surface, and hydrogen is scattered forward and helium is scattered backward by elastic scattering, and the amount of hydrogen is quantified by detecting the hydrogen. At this time, the measurement depth of the hydrogen amount is 400 to 500 nm from the surface 10a. Therefore, in the structure 10, the microstructure of the surface 10a that most affects the particle resistance can be appropriately quantified.

Third Aspect of the Present Invention As a finding that forms the basis of the third aspect of the present invention, it has been found that a new index called luminance Sa has a high correlation with particle resistance performance at an extremely high level. Then, a structure excellent in particle resistance, in which the luminance Sa was set to a predetermined value or less, was successfully formed. That is, it was found that a structure having extremely high particle resistance was obtained, and that the particle resistance could be quantified by the luminance Sa. Further, an evaluation method for obtaining the luminance Sa has been established.

  Furthermore, the present inventors have found that the luminance Sa correlated with the particle resistance is further reduced in the structure of ceramics, especially in the structure in which the porosity is evaluated to be 0.01 to 0.1% (finer structure). Structure) can be evaluated.

The composite structure according to the third aspect of the present invention comprises:
A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure comprises polycrystalline ceramics,
A composite structure having a luminance Sa value calculated by the following method of 19 or less:
The method for obtaining the luminance Sa is as follows:
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) preparing a digital black and white image of a bright field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method: Focused Ion Beam method) to suppress processing damage,
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
In the step (v),
For each of the luminance acquisition areas, an average of absolute values of the differences between the corrected luminance values for each pixel is calculated using a least squares method, and the average is set as the luminance Sa. Things.

The evaluation method according to the third aspect of the present invention includes:
A method for evaluating a microstructure of a structure having a surface, including a polycrystalline ceramic,
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) preparing a digital black and white image of a bright field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
In the step (v),
For each of the luminance acquisition areas, an average of absolute values of the differences between the corrected luminance values for each pixel is calculated using a least squares method, and the average is set as the luminance Sa. Things.

Luminance Sa according to the third embodiment of the present invention
In the third aspect of the present invention, the microstructure of the structure is represented by an index called “luminance Sa”. This “luminance Sa” is an index obtained by quantifying pixel information of a digital black-and-white image of a bright-field image of the structure obtained by a transmission electron microscope (TEM), as described in detail below. . The structure of the composite structure according to the present invention is characterized in that the luminance Sa is 19 or less, preferably 13 or less.

  The present inventors can evaluate a finer structure in a ceramic structure, particularly a structure in which the porosity is evaluated to be 0.01 to 0.1%, in which the luminance Sa correlated with the particle resistance is evaluated. It was mentioned above that it was found to be a good index. Therefore, in the present invention, the “microstructure” refers to a structure having a porosity of 0.01 to 0.1%, a higher level of particle resistance, and a difference in luminance Sa. Means a fine structure in the region where

  In the present specification, the “brightness value” represents color data of each pixel in a digital monochrome image represented by numerical values of gradation (0 to 255). Here, the “gradation” is a brightness level. Specifically, a color value of each pixel in a black-and-white image represented by 256 numerical values corresponding to different brightness levels is referred to as a luminance value (“Image processing apparatus and its usage”, Nikkan Kogyo Shimbun) 1989, first edition, p. 227). The black and white contrast in the TEM black and white image is represented as a luminance value.

  In this specification, the term “brightness Sa” refers to the concept of Sa (arithmetic mean height of the surface) defined in the international standard ISO25178 concerning three-dimensional surface texture applied to image processing of digital TEM images. Things. This will be specifically described with reference to FIG. 5 in which luminance values of a digital TEM image are three-dimensionally displayed. FIG. 5A is a digital black-and-white image of a structure that is a TEM bright-field image. FIG. 5B shows the digital black and white image in which the color data for each pixel is represented by a numerical value of gradation (0 to 255) and the numerical value is represented in the Z-axis direction. That is, in FIG. 5B, the Z axis is the luminance value, and the luminance value for each pixel on the XY plane is represented in three dimensions. The three-dimensional image of the luminance value is regarded as a three-dimensional image of the surface texture defined in ISO25178 (for example, see the following URL: https://www.keyence.co.jp/ss/3dprofiler/arasa/surface/), For the evaluation area, the average of the absolute value of the difference between the luminance values for each pixel is calculated using the least squares method, and the result is defined as “luminance Sa”.

  Next, “luminance Sa” in the present specification is roughly calculated as follows.

-In the calculation of the luminance Sa in the present invention, a TEM observation sample for obtaining a digital black-and-white image is formed using a focused ion beam method (FIB method) while suppressing processing damage. During FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure. When the FIB processing direction is the vertical direction, the thickness of the upper part of the sample, which is the length in the minor axis direction of the surface of the structure, on a plane perpendicular to the vertical direction is 100 ± 30 nm. At least three TEM observation samples are prepared from one structure.
Obtaining digital black and white images for each of the at least three TEM observation samples; Digital black and white images are acquired using a transmission electron microscope (TEM) at a magnification of 100,000 and an acceleration voltage of 200 kV. Digital black and white images include structures, carbon layers, and tungsten layers.
In a digital black and white image, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the structure surface is set. A plurality of the digital black-and-white images are obtained from each of at least three TEM observation samples so that the total area of the brightness acquisition regions is 6.9 μm ² or more.
-With respect to the luminance value of the color data for each pixel in the acquired digital black and white image represented by the numerical value of the gradation, the luminance value of the carbon layer is 255 and the luminance value of the tungsten layer is relatively corrected as 0.
Using the corrected luminance value, calculate the luminance Sa as follows. That is, for each of the luminance acquisition regions, the average of the absolute values of the differences between the corrected luminance values for each pixel is calculated using the least squares method, and the average is set as the luminance Sa.

  Hereinafter, the method of calculating the luminance Sa will be described in more detail with reference to FIGS.

FIG. 2 is a flowchart illustrating a method of calculating the luminance Sa. A description will be given below with reference to this flowchart.
(i): Preparation of TEM observation sample This step is a step of preparing a sample for TEM observation. This step will be described with reference to FIG. The TEM observation sample is created by a focused ion beam method (FIB method, Focused Ion Beam method). In the processing by the FIB method, a thin film can be formed aiming at a place to be observed (“Surface analysis technology selection transmission electron microscope” edited by The Surface Chemistry Society of Japan, Maruzen Co., Ltd., published on March 30, 1999).

  First, the structure 10 is cut in advance using a dicing machine or the like. At this time, a portion corresponding to a sample acquisition location 40 in FIGS. 8 and 9 described below is first cut out. Then, FIB processing is performed on the surface 10a of the structure, and processed into the shape shown in FIG. At this time, the arrow L in FIG. The vertical direction L is substantially parallel to the thickness direction of the structure 10. The vertical direction L is substantially the same as the vertical direction defined in the above-mentioned FIB processing direction.

  FIB processing will be described in more detail. A carbon layer 50 is deposited on the surface 10a of the structure 10 after the dicing process in order to suppress charge-up and protect the structure surface 10a. The deposition thickness of the carbon layer 50 is about 300 nm. Here, before forming the carbon layer 50, it is preferable to smooth the structure surface 10a by polishing or the like.

  Next, the structure 10 on which the carbon layer 50 has been deposited is sliced using a focused ion beam (FIB) apparatus. Specifically, first, a portion of the structure 10 is cut out together with the carbon layer 50 by irradiating a Ga ion beam around the portion to be sliced with the carbon layer 50 facing upward. The cut-out structure 10 is fixed to a FIB TEM sample table by a FIB pickup method using a tungsten deposition function. Next, in order to obtain a TEM observation sample 90, the cut structure 10 is sliced. In this procedure for thinning, first, a tungsten layer 60 is formed by a tungsten deposition process on the carbon layer 50 of the structure 10 and at a portion to be thinned for TEM observation. By providing the tungsten layer 60, it is possible to suppress the destruction of the TEM observation sample surface by the Ga ion beam during processing. The thickness of the tungsten layer 60 to be deposited is 500 to 600 nm. Then, the structure is shaved from both sides at the thinned portion with Ga ions, and a TEM observation sample 90 having a predetermined thickness (length along the arrow T in the figure) is produced.

  In the present invention, when the TEM observation sample 90 is manufactured, the TEM observation sample 90 is manufactured so as to suppress processing damage such as unevenness damage on the processing surface. Specifically, the accelerating voltage at the time of FIB processing is started from the maximum voltage of 40 kV, and finally, the finishing processing is performed at the minimum voltage of 5 kV in order to avoid damage to the processed surface of the structure and formation of the amorphous layer as much as possible. Alternatively, the damaged layer is finally removed by Ar ions. Observation may be performed after cleaning the surface by ion milling. For details of these FIB processes, see "Fine Machining Using FIB Apparatus" (Mitsuhiro Muroi, University of Tsukuba Technical Report 24: 69-72, 2004), "FIB / Ion Milling Technique Q & A" (Masao Hirasaka, Kentaro Asakura, Agune Shofusha).

  FIGS. 3A and 3B are schematic diagrams of the TEM observation sample 90 obtained as described above. As shown in FIGS. 3A and 3B, the TEM observation sample 90 has a thin rectangular parallelepiped shape. 3, in two directions perpendicular to the longitudinal direction L, the major axis direction is defined as the horizontal direction W (arrow W in the figure), and the minor axis direction is defined as the thickness direction T (arrow T in the figure). As shown in FIG. 3A, in the TEM observation, the electron beam is transmitted in the thickness direction T.

  As shown in FIG. 3A, since the thinning by Ga ions is performed from the top of the drawing, the sample 90 tends to have a lower thickness 90b larger than its upper thickness 90u. Here, the upper thickness 90u is the length of the sample 90 in the thickness direction T on the surface 10a side. The thickness of the TEM observation sample 90 affects the electron beam transmission ability. Specifically, when the sample thickness is too large, the sensitivity of the luminance Sa becomes low and a correlation with the particle resistance performance may not be obtained. If the sample thickness is too small, it is difficult to control the thickness at the time of processing, the thickness will vary within the TEM observation sample 90, and there is a possibility that a correlation with the particle resistance performance cannot be obtained. In the present invention, the upper thickness 90u is 100 nm ± 30 nm, more preferably 100 nm ± 20 nm.

  Further, in the present invention, in order to calculate the luminance Sa by image analysis using a TEM digital monochrome image, the difference in the thickness of the TEM observation sample 90 along the longitudinal direction L (the difference between the upper thickness 90u and the lower thickness 90b). (Difference) as small as possible. Normally, the sample has the form shown in FIG. 3A, and the sample height 90h (the length in the vertical direction L) is about 10 μm, and the sample width 90w (the length in the horizontal direction W) is tens μm to several tens. It is about μm.

  The method for confirming the upper thickness 90u of the TEM observation sample 90 is as follows. For the TEM observation sample 90, a secondary electron image (see FIG. 3C) is acquired using a scanning electron microscope (SEM), and an upper thickness 90u is obtained from the secondary electron image. For the SEM, for example, S-5500 manufactured by HITACHI is used. The SEM observation conditions are a magnification of 200,000 times, an acceleration voltage of 2 kV, a scan time of 40 seconds, and an image number of 2560 * 1920 pixels. At this time, the SEM image is to be a plane perpendicular to the longitudinal direction L. Using the scale bar of this SEM image, an upper thickness of 90 u is obtained. At this time, the upper thickness 90u is an average value of five times.

  An alternative method of confirming the upper thickness 90u is as follows. That is, the luminance value of the digital image of the secondary electron image is measured along the thickness direction T to obtain a luminance line profile. At this time, the line width is set to 11 pixels, and the average value of the luminance values for 11 pixels in the line width direction is used. FIG. 3D shows an example of the luminance line profile thus obtained. Next, the luminance line profile is first-order differentiated, and a maximum value and a minimum value of the first-order differentiation are set as ends of the structure 10 to obtain an upper thickness 90u of the structure 10 (see FIG. 3E). At this time, the upper thickness 90u is an average value of the five luminance line profiles.

  In the calculation of the luminance Sa in the present invention, at least three TEM observation samples 90 are prepared from one composite structure. The preparation of at least three TEM observation samples will be further described with reference to FIGS.

  FIGS. 8 and 9 are schematic diagrams illustrating an example in which the composite structure 100 is used as the semiconductor manufacturing apparatus member 301. FIG. In FIG. 8, in a semiconductor manufacturing apparatus member 301, a structure 10 is provided on a surface 70a of a columnar base material 70. In FIG. 9, in a semiconductor manufacturing apparatus member 302, a structure 10 is provided on a surface 70 a of a columnar base material 70 in which a hole 31 is provided in the center.

  In the semiconductor manufacturing apparatus members 301 and 302, the surface 10a of the structure 10 is exposed to corrosive plasma. The semiconductor manufacturing apparatus members 301 and 302 are members constituting an inner wall of the etching chamber, such as a shower plate, a focus ring, a window, and a sight glass. When the structure 10 has the plasma irradiation region 30a and the plasma non-irradiation region 30b that is not exposed to the plasma, the brightness Sa measurement sample acquisition position 40 is set to a position corresponding to the plasma irradiation region 30a. At this time, if there is a region irradiated with a lot of plasma, the structure surface 10a corresponding to the region is set as the sample acquisition location 40, so that the correlation between the particle resistance and the luminance Sa can be improved. it can.

  In the present invention, at least three sample acquisition points 40 for measuring the luminance Sa for producing the TEM observation sample 90 are provided. At this time, as shown in FIGS. 8 and 9, a plurality of sample acquisition locations 40 are uniformly arranged in the plasma irradiation region 30a. Thereby, a high correlation between the luminance Sa of the composite structure 100 and the particle resistance can be secured.

(Ii): Acquisition of TEM image G (bright-field image) In this step, a cross section of each of at least three TEM observation samples 90 obtained in (i) was taken with a TEM at a magnification of 100,000 and an accelerating voltage of 200 kV. To obtain a TEM image G (see FIG. 4) including the structure 10, the carbon layer 50, and the tungsten layer 60. The cross section of the TEM observation sample 90 is a cross section of the composite structure 100 shown in FIG. 1, more specifically, a cross section including the vicinity of the surface 10 a of the structure 10. At this time, a bright field image is acquired. A bright-field image is an image formed by passing only a transmitted wave through an objective aperture (“Surface Analysis Technology Selection Transmission Electron Microscope”, edited by The Surface Chemistry Society of Japan, Maruzen Co., Ltd., issued March 30, 1999, 43- 44).

  For photographing the TEM image G, for example, a transmission electron microscope (H-9500 / manufactured by Hitachi High-Technologies) is used. The accelerating voltage is 200 kV, and a digital camera (manufactured by OneView Camera Model 1095 / Gatan) is used to set the image capturing mode to 4096 × 4096 pixels, a capture speed of 6 fps, an exposure time of 2 sec. Perform under the same conditions as As shown in FIG. 4, in acquiring the image G, the structure 10, the structure surface 10a, the carbon layer 50, and the tungsten layer 60 are set in the same field of view.

  In the present invention, the luminance Sa is calculated by image analysis of the luminance information of the digital image. Therefore, focus accuracy in photographing is extremely important. Therefore, for example, when acquiring a 100,000-times TEM image, a 100,000-times TEM image is acquired after adjusting the focus at a high magnification of 300,000 times or more.

  The TEM image G which is a digital monochrome image will be further described with reference to FIG. FIG. 4 is a schematic diagram of a TEM image G (bright-field image). In the figure, a square portion having a vertical length Gl and a horizontal length Gw is the TEM image G. In FIG. 4, on the surface 10a of the structure 10, there are images corresponding to the carbon layer 50 and the tungsten layer 60 deposited in the step (i). The portion below the surface 10a corresponds to the structure 10. In the TEM image G, the carbon layer 50 is white to light gray, and the tungsten layer 60 is black.

  Note that in this specification, in the TEM image G, the direction in which the structure 10, the carbon layer 50, and the tungsten layer 60 are arranged, that is, the direction indicated by the arrow L in FIG. The direction of the arrow W in the figure, which is perpendicular to the direction, is referred to as the “lateral direction”. This vertical direction L corresponds to the vertical direction L in FIG.

  The physical properties and characteristics of the composite structure according to the present invention, for example, the particle resistance, are governed by the properties near the surface of the structure. The present inventors have found that the luminance Sa in a region where the vertical length dL along the vertical direction L from the structure surface 10a is 0.5 μm is most correlated with physical properties and characteristics such as particle resistance. The image vertical length Gl and the image horizontal length Gw of a TEM image obtained at a magnification of 100,000 times are generally about 1.5 μm to 2.0 μm, respectively, depending on the camera. . Therefore, in the present invention, the brightness acquisition region R is set using the TEM image of 100,000 times, the region vertical length dL is set to 0.5 μm, and the brightness Sa is determined from the brightness value in the brightness acquisition region R.

In the present invention, the brightness acquisition region R is set for each image G. Then, a plurality of digital black-and-white images are acquired from at least three TEM observation samples so that the total area of the luminance acquisition regions R is 6.9 μm ² or more. At this time, the number of images G obtained from each TEM observation sample is set to be the same. Details of the total area of the brightness acquisition region R will be described later.

(Iii): Acquisition of luminance value Next, in this step, for each of the “vertical” and “horizontal” coordinates in the TEM image G, which is the digital black and white image acquired in step (ii), the corresponding pixel Get the brightness value for each. Here, the luminance value of the tungsten layer and the luminance value of the carbon layer in the image G are also included. FIG. 5A is a plan view illustrating an example of the acquired TEM image G. The arrow Y in FIG. 5A corresponds to the vertical direction L in FIGS. The arrow X in FIG. 5A corresponds to the horizontal direction W in FIGS. FIG. 5B is a diagram in which the brightness value of each pixel in the image G is three-dimensionally represented in the arrow Z direction.

(Iv): Step of Correcting Brightness Value Next, in this step, an operation of correcting the brightness value of the TEM image G obtained in the step (iii) is performed. The specific contents will be described with reference to FIG. FIG. 6A is a diagram in which the brightness values of the TEM image G acquired in the step (iii) are three-dimensionally expressed for each pixel corresponding to the vertical and horizontal coordinates of the structure 10. It is. Here, as in the step (iii), the luminance value of the tungsten layer and the luminance value of the carbon layer in the image G are also included. In this step, the brightness value of the tungsten layer 60 in the image G is set to 0, the brightness value of the carbon layer 50 in the image G is set to 255, and the brightness value corresponding to the structure 10 is set for each pixel. Is corrected relative to. As described above, in the TEM image G, the tungsten layer 60 is black, and the carbon layer 50 is white to light gray. In this step, the luminance value of each pixel of the structure 10 is corrected and determined as a relative value between the luminance value 0 of the tungsten layer and the luminance value 255 of the carbon layer. FIG. 6B is a diagram three-dimensionally representing the luminance value of the image G after the correction. In comparison with FIG. 5, it can be seen that the luminance value of the structure 10 is relatively corrected based on black of the tungsten layer 60 and white to light gray of the carbon layer 50.

  In the TEM image G, the brightness value of each pixel of the carbon layer 50 / tungsten layer 60 usually shows a slight variation. In order to eliminate the influence of this variation, the values for the luminance value 0 of the tungsten layer and the luminance value 255 of the carbon layer are determined as follows. As the luminance value of the tungsten layer 60, the average value of the luminance values of 10,000 pixels is used in ascending order from the minimum luminance value in the tungsten layer 60 in the image G. As the luminance value of the carbon layer 50, the average value of the luminance values of 100,000 pixels is used in ascending order from the maximum luminance value in the carbon layer 50. The respective average values obtained here are treated as luminance values of the carbon layer 50 / tungsten layer 60 before correction. The brightness values of the plurality of TEM images G are similarly corrected.

(V): Calculation of luminance Sa In this step, the luminance Sa is calculated from the luminance value of the image G obtained in the step (iv). Specifically, for each of the luminance obtaining region R described above (hereinafter, the respective brightness acquisition area is expressed as R _n), the absolute of the difference between the luminance value after correction for each pixel by using the least square method calculating the average value, the average of them as the brightness Sa _n region R _n. The luminance of the luminance acquisition region _{R 1 + 2 + ··· + n} total area luminance Sa _n mean the structure 10 of the calculated plurality of luminance obtaining region _{R n} which is set to be 6.9 [mu] m ² or more of Sa.

In the present invention, the area of the luminance acquisition region R is set to 6.9 μm ² or more in calculating the luminance Sa in order to increase the correlation between the luminance Sa and the physical properties and characteristics of the structure, for example, the particle resistance. I do. By determining the luminance Sa on the basis of a region exceeding this area, the correlation between the luminance Sa and the physical properties and the like can be obtained even when there is a possibility that the physical properties and characteristics may vary in the limited region in the structure 10. Can be accurately and properly represented.

The size of one TEM observation sample 90 is very small with respect to the surface area of the structure 10, that is, the plasma irradiation area. On the other hand, physical properties and characteristics imparted to the structure, for example, particle resistance, are required in principle on the entire structure surface. In this regard, in the present invention, a total area of the luminance acquisition region R of 6.9 μm ² or more is required, and at least three TEM observation samples are created from the structure 10. That is, in the present invention, a plurality of TEM observation samples are uniformly obtained from the structure surface so as to cover as much information as possible on the entire structure surface. In obtaining at least three or more TEM observation samples, care must be taken so that information on the entire structure surface is covered.

  The luminance Sa correlates with the physical properties and characteristics of the structure, for example, the particle resistance. Therefore, according to the present invention, by calculating the luminance Sa of the structure, the performance such as the particle resistance of the structure is grasped before using the structure instead of evaluating the actual particle resistance of the structure. be able to.

  The process of calculating the luminance Sa will be described in more detail mainly on the description regarding the area of the luminance acquisition region R.

In order to enhance the correlation between the luminance Sa and the particle resistance, in the present invention, the luminance acquisition region R in the image G is set so that the total area thereof is 6.9 μm ² or more. Specifically, to get the image G _n of a plurality of (n) from at least three TEM observation sample for each of the images to set the region R _n. Then, an average value of the luminance Sa _n of each image Gn, and the brightness Sa of the structure.

4, FIGS. 6 (a) and, with reference to FIG. 7 (a) ~ (b) , a description will be given of a method of calculating one luminance Sa ₁ from the image _{G 1.}

As shown in FIG. 4 and 6 (a), for one of the image _{G 1,} it sets a region _{R 1.} In one region _{R 1,} the region vertical length dL and 0.5 [mu] m. This is because, as described above, the properties near the surface of the structure are considered to be most correlated with the properties and characteristics of the structure, for example, the particle resistance. Also, as an area horizontal length dW lateral direction W of the region R _1, it is set to be the longest in the image G. As an example, at a magnification of 100,000, the lateral width dW of the region is about 1.5 μm to 2.0 μm. In other words, the region _{R 1} area that can be set for the magnification 100,000 one taken at times TEM image _{G 1} becomes 0.75~1.0μm ^2.

Thus, in this example, the number of image G necessary for the total area of the brightness acquisition region _{R n} and 6.9 [mu] m ² becomes 7-9 sheets. On the other hand, as described above, in the present invention, at least three TEM observation samples 90 are prepared, and the same number of TEM images G are obtained from each TEM observation sample 90. Therefore, in this example, three images G are acquired for one TEM observation sample 90. When acquiring a plurality of TEM images _Gn from one TEM observation sample 90, the plurality of images _Gn are acquired so as to be continuous in the horizontal direction W as shown in FIG. In addition, the sizes of the plurality of images _Gn (the image vertical length Gl and the image horizontal length Gw) are substantially the same. Thereby, for example, the influence of measurement variation between observers can be reduced, and the correlation between the luminance Sa and the particle resistance can be further increased.

  As described above, the present inventors have found that the luminance Sa in the region of 0.5 μm from the structure surface 10a is most correlated with the physical properties and characteristics of the structure, for example, the particle resistance. Therefore, in the region R when calculating the luminance Sa, the region vertical length dL is set to 0.5 μm. Further, in step (i), as described with reference to FIG. 3, since the processing is performed from the direction of the surface 10 a of the structure 10, even when the processing accuracy is increased, the thickness of the TEM observation sample 90 is smaller than the sample upper thickness 90 u. 90d becomes a large tapered shape. Therefore, as the depth from the surface 10a of the structure 10 increases, the electron beam becomes more difficult to transmit, and the sensitivity of the luminance value decreases. That is, in the image G, the image becomes darker as a whole in the depth direction with respect to the surface 10a side, that is, the image becomes darker. Therefore, in order to sufficiently reduce the influence of the sample thickness, the region vertical length dL needs to be 0.5 μm.

  When setting the brightness acquisition region R, the region vertical length dL is set based on the vicinity of the surface 10a of the structure 10 as a base point. When a gap is observed between the surface 10a and the carbon layer 50 in the TEM image G, it is necessary to set the region R to avoid the gap. "Near the surface 10a" refers to a range of about 5 to 50 nm from the surface 10a. Details of specific settings can be made with reference to the examples described later.

  The processes in the above steps (iii) to (iv) can be performed continuously and collectively by image analysis software. Such software includes WinROOF2015 (available from Mitani Corporation). Can be used.

  It is considered that the smaller the brightness Sa of the structure of the composite structure according to the present invention, the better, but it is apparent to those skilled in the art that there is a practical limit in manufacturing. Since such a manufacturing limit becomes the lower limit value of the luminance Sa in the present invention, the fact that the lower limit value is not specifically specified does not obscure the present invention according to the third aspect. Absent. This point is the same in the following fourth embodiment.

Fourth Aspect of the Present Invention In a fourth aspect of the present invention, the luminance Sa is used as an index similarly to the third aspect of the present invention, but the step (iv) in the method for obtaining the luminance Sa in the first aspect That is, in the step of correcting the luminance value, a step of removing a noise component is added. Therefore, the description of the third embodiment in this specification other than the step of removing the noise component is the description of the fourth invention.

And the composite structure according to the fourth aspect of the present invention is:
A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure comprises polycrystalline ceramics,
A composite structure, wherein the luminance Sa value calculated by the following method is 10 or less:
The method for obtaining the luminance Sa is as follows:
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) obtaining a digital black-and-white image of a bright-field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
A noise removal using a low-pass filter is performed on the digital black-and-white image whose luminance value has been corrected, wherein a cut-off frequency in the noise removal using the low-pass filter is 1 / (10 pixels )
In the step (v),
For each of the luminance acquisition areas, an average of absolute values of the differences between the corrected luminance values for each pixel is calculated using a least squares method, and the average is set as the luminance Sa. Things.

Further, the evaluation method according to the present invention,
A method for evaluating a microstructure of a structure having a surface, including a polycrystalline ceramic,
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) obtaining a digital black-and-white image of a bright-field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
A noise removal using a low-pass filter is performed on the digital black-and-white image whose luminance value has been corrected, wherein a cut-off frequency in the noise removal using the low-pass filter is 1 / (10 pixels )
In the step (v), for each of the luminance acquisition regions, an average of absolute values of the differences between the corrected luminance values for each pixel is calculated using a least squares method, and the average is calculated as a luminance Sa. It is characterized by the following.

  As described above, the composite structure according to the fourth embodiment is characterized in that the luminance Sa is 10 or less, and preferably 5 or less.

  In the fourth embodiment of the present invention, step (i), that is, a step of preparing a transmission electron microscope (TEM) observation sample of the structure, in order to obtain the luminance Sa as in the third embodiment of the present invention. And step (ii), that is, a step of preparing a digital black-and-white image of a bright-field image of the TEM observation sample, and step (iii), that is, color data of each pixel in the digital black-and-white image is represented by a numerical value of gradation. The step of acquiring the obtained luminance value is performed. Further, in the step (iv), a step of removing a noise component from the image is performed as necessary so that the luminance Sa more accurately and appropriately represents the microstructure of the structure. The TEM image G contains noise having a high frequency component, and is removed by a filter in this additional step. In this embodiment, noise removal is performed on the image G using a low-pass filter (LPF). For details of noise removal in image processing, see "Image Processing-Second Edition from Basics to Applications" (by Hiroshi Ozaki and Keiji Taniguchi, Kyoritsu Shuppan Co., Ltd.).

  In this embodiment, a cut-off frequency in noise removal using a low-pass filter is set to 1 / (10 pixels). That is, the cutoff period is set to 10 pixels. For example, when WinROOF2015 is used as image processing software, a cutoff frequency is set using a noise removal command.

  FIGS. 7 (c) and 7 (d) show the image G after the luminance value correction. FIGS. 7 (a) and 7 (b) show the noise removal using a low-pass filter as the cutoff frequency 1 / (10 pixels). It is an example of an image. By performing the noise removal, it is possible to eliminate the influence of the focus accuracy of the TEM image G and the like, and it is possible to enhance the physical properties and characteristics of the structure, for example, the correlation between the particle resistance and the luminance Sa.

  In the fourth aspect of the present invention, the step (v) of calculating the luminance Sa using the corrected luminance value thus obtained is performed thereafter. This step (v) may be the same as in the third embodiment of the present invention.

Fifth Aspect of the Present Invention In a fifth aspect of the present invention, unlike the first to fourth aspects of the present invention, the object includes Y (yttrium element) and O (oxygen element). While limited to the structure, the microstructure of the structure is expressed using the refractive index as an index. That is, the present inventors have developed a composite structure including a structure containing Y (yttrium element) and O (oxygen element) used in a situation exposed to a corrosive plasma environment such as a semiconductor manufacturing apparatus. We succeeded in minimizing the effects of particles. Then, they have found that particle resistance performance can be evaluated at an extremely high level by using the refractive index as an index.

The composite structure according to the fifth aspect of the present invention comprises:
A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure includes a polycrystalline ceramic containing Y (yttrium element) and O (oxygen element);
The refractive index at a wavelength of 400 nm to 550 nm is larger than 1.92,
The refractive index is calculated by reflection spectroscopy using a microspectrophotometer,
As measurement conditions, the measurement spot size is 10 μm, the average surface roughness Ra of the substrate surface and the composite structure surface is ≦ 0.1 μm, the thickness of the structure is ≦ 1 μm, and the measurement wavelength range is 360 to 1100 nm.
As the analysis conditions, an analysis wavelength range of 360 to 1100 nm, an optimization method, and a least squares method are used.

Further, the composite structure according to the fifth other aspect of the present invention includes:
A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure comprises a polycrystalline ceramic containing Y (yttrium element) and O (oxygen element);
The refractive index is at least one of 1.99 or more at a wavelength of 400 nm, 1.96 or more at a wavelength of 500 nm, 1.94 or more at a wavelength of 600 nm, 1.93 or more at a wavelength of 700 nm, and 1.92 or more at a wavelength of 800 nm or more. Is satisfied, using a microspectrophotometer, is calculated by reflection spectroscopy,
As measurement conditions, the measurement spot size is 10 μm, the average surface roughness Ra of the substrate surface and the composite structure surface is ≦ 0.1 μm, the thickness of the structure is ≦ 1 μm, and the measurement wavelength range is 360 to 1100 nm.
As the analysis conditions, an analysis wavelength range of 360 to 1100 nm, an optimization method, and a least squares method are used.

In general, the average refractive index of Y ₂ O ₃ is 1.92 (Chemical Handbook, edited by The Chemical Society of Japan, Maruzen (1962), p919, “Ceramic Chemistry” p220, Table 8-24, Japan Ceramics Co., Ltd. Association, revised version on September 30, 1994). Also, the Chemical Society of Japan 1979, (8), p. 1106 to 1108 (Non-Patent Document 1) disclose a refractive index and a reflectance as optical characteristics of a transparent plate-like sample yttrium oxide sintered body (see FIG. 20). In contrast, the composite structure according to the fifth aspect of the present invention has, for example, a refractive index at a wavelength of 400 to 550 nm greater than 1.92. Alternatively, it satisfies at least one of 1.99 or more at a wavelength of 400 nm, 1.96 or more at a wavelength of 500 nm, 1.94 or more at a wavelength of 600 nm, 1.93 or more at a wavelength of 700 nm, and 1.92 or more at a wavelength of 800 nm or more.

  In the fifth embodiment, the basic structure of the composite structure is the same as the composite structures according to the first to fourth embodiments, except that in the basic structure in FIG. 1, the structure 10 is formed of Y (yttrium element). And a polycrystalline ceramic containing O (oxygen element) (hereinafter sometimes referred to as “YO compound”). The structure 10 provided in the composite structure has a predetermined refractive index.

  Therefore, the structure 10 including Y (yttrium element) and O (oxygen element) included in the composite structure according to the fifth embodiment is a so-called YO compound coat. By applying the YO compound coat, the base material 70 can be given various physical properties and characteristics. In this embodiment, the ceramic structure and the ceramic coat are used synonymously unless otherwise specified.

  According to one preferred embodiment, the structure 10 is mainly composed of a polycrystalline ceramic containing a YO compound, and preferably contains the YO compound in an amount of more than 50%, more preferably 70% or more, even more preferably 90% or more. , 95% or more. Most preferably, structure 10 comprises a YO compound.

In this embodiment, the YO compound is, for example, an oxide of yttrium. For example, Y ₂ O ₃ and Y _α O _β (non-stoichiometric composition) can be mentioned. In addition to the Y element and the O element, other elements may be included. For example, a YO compound further containing at least one of the F element, the Cl element, and the Br element can be used. The structure 10 includes, for example, Y ₂ O ₃ as a main component. The content of Y ₂ O ₃ is 70% or more, preferably 90% or more, more preferably 95% or more. Most preferably, structure 10 comprises 100% Y ₂ O ₃ .

The refractive index in the fifth embodiment may be measured by reflection spectroscopy using a microspectrophotometer (for example, OPTM-F2, FE-37S, manufactured by Otsuka Electronics Co., Ltd.). The measurement conditions are a measurement spot size of 10 μm and a measurement wavelength range of 360 to 1100 nm. The analysis condition is an analysis wavelength range of 360 to 1100 nm, and the optimization method and the least squares method are used.

  In the composite structure according to the fifth aspect of the present invention, the refractive index at a wavelength of 400 nm to 550 nm is larger than 1.92, preferably the refractive index at a wavelength of 400 nm to 600 nm is larger than 1.92, more preferably 400 nm to 800 nm. Is greater than 1.92. In the composite structure according to the fifth aspect of the present invention, the refractive index is 1.99 or more at a wavelength of 400 nm, 1.96 or more at a wavelength of 500 nm, 1.94 or more at a wavelength of 600 nm, and 1.93 or more at a wavelength of 700 nm. And at least 1.92 at a wavelength of 800 nm or more. The present inventors have newly found a novel structure that increases the refractive index as described above in a composite structure containing a YO compound. Surprisingly, the present inventors have found that a composite structure containing a YO compound having a very high refractive index has extremely excellent particle resistance, and arrived at the present invention. In one preferred embodiment of the present invention, the upper limit of the refractive index is 2.20.

Method for Preparing Composite Structure The composite structure according to the present invention may be manufactured by any suitable manufacturing method as long as the structure having the indicators of the first to fifth aspects described above can be realized. According to one aspect of the present invention, the composite structure according to the present invention can be preferably manufactured by forming the structure on a substrate by an aerosol deposition method (AD method). According to one preferred embodiment of the present invention, the structure of the composite structure according to the present invention can be realized by an AD method. In the AD method, an aerosol in which fine particles of a brittle material such as ceramics and a gas are mixed is sprayed onto the surface of the base material, and the fine particles collide with the base material at a high speed. This is a method of forming a structure (ceramic coat) on a material.

Apparatus for performing the AD method The apparatus used for the AD method for manufacturing the composite structure according to the first to fifth aspects of the present invention is not particularly limited, but has a basic configuration shown in FIG. That is, the device 19 used for the AD method includes the chamber 14, the aerosol supply unit 13, the gas supply unit 11, the exhaust unit 18, and the pipe 12. Inside the chamber 14, a stage 16 on which the base material 70 is arranged, a driving unit 17, and a nozzle 15 are arranged. The position of the base material 70 and the nozzle 15 arranged on the stage 16 can be relatively changed by the driving unit 17. At this time, the distance between the nozzle 15 and the substrate 70 may be constant or may be variable. In this example, the driving unit 17 drives the stage 16, but the driving unit 17 may drive the nozzle 15. The driving direction is, for example, the XYZθ direction.

  In the apparatus shown in FIG. 10, the aerosol supply unit 13 is connected to the gas supply unit 11 by a pipe 12. In the aerosol supply unit 13, the aerosol in which the raw material fine particles and the gas are mixed is supplied to the nozzle 15 via the pipe 12. The apparatus 19 further includes a powder supply unit (not shown) for supplying raw material fine particles. The powder supply unit may be arranged in the aerosol supply unit 13 or may be arranged separately from the aerosol supply unit 13. In addition to the aerosol supply unit 13, an aerosol forming unit that mixes the raw material fine particles and the gas may be provided. By controlling the supply amount from the aerosol supply unit 13 so that the amount of fine particles injected from the nozzle 15 is constant, a uniform structure can be obtained.

  The gas supply unit 11 supplies nitrogen gas, helium gas, argon gas, air, and the like. When the supplied gas is air, for example, it is preferable to use compressed air having a small amount of impurities such as moisture and oil, or to further provide an air treatment unit for removing impurities from the air.

  Next, the operation of the device 19 used for the AD method will be described. With the substrate placed on the stage 16 in the chamber 14, the inside of the chamber 14 is evacuated to a pressure lower than the atmospheric pressure, specifically about several hundred Pa, by an exhaust unit 18 such as a vacuum pump. On the other hand, the internal pressure of the aerosol supply unit 13 is set higher than the internal pressure of the chamber 14. The internal pressure of the aerosol supply unit 13 is, for example, several hundreds to several tens of thousands Pa. The powder supply unit may be at atmospheric pressure. The fine particles in the aerosol are accelerated by the pressure difference between the chamber 14 and the aerosol supply unit 13 so that the injection speed of the raw material particles from the nozzle 15 is in a subsonic to supersonic (50 to 500 m / s) region. . The injection speed is appropriately controlled by the flow rate of the gas supplied from the gas supply unit 11, the gas type, the shape of the nozzle 15, the length and inner diameter of the pipe 12, the amount of exhaust of the exhaust unit 18, and the like. For example, a supersonic nozzle such as a Laval nozzle can be used as the nozzle 15. The fine particles in the aerosol ejected at a high speed from the nozzle 15 collide with the base material and are crushed or deformed and deposited as a structure on the base material. By changing the relative position between the substrate and the nozzle 15, a composite structure having a structure having a predetermined area on the substrate is formed. Specific manufacturing conditions such as the pressure in the chamber and the gas flow rate vary depending on the combination of individual devices, and these conditions can be appropriately adjusted as long as the structure of the present invention can be formed.

  Before being ejected from the nozzle 15, a crushing unit (not shown) for breaking up the aggregation of the fine particles may be provided. An arbitrary method can be selected as the method of crushing in the crushing unit, as long as the below-described mode of collision of the fine particles with the base material is satisfied. For example, known methods such as vibration, mechanical crushing such as collision, static electricity, plasma irradiation, classification and the like can be mentioned.

  The composite structure according to the present invention is preferably used in the following applications in addition to the above. That is, coatings for the aerospace industry, such as electric vehicles, touch panels, LEDs, solar cells, dental implants, satellite mirrors, corrosion-resistant coatings on sliding members, chemical plants, etc., all-solid-state batteries, thermal barrier coatings, high refractive indexes It is preferably used in applications such as optical lenses, optical mirrors, optical elements, and jewelry.

  The present invention will be further described by the following examples, but the present invention is not limited to these examples.

1. Sample preparation
1-1 Raw material particles As raw material particles, yttrium oxide, yttrium oxyfluoride, yttrium fluoride, aluminum oxide powder, and zirconium oxide powder were prepared. The average particle size and particle state of the various powders were as shown in Table 1.

1-2 Film Formation of Samples Using the raw material particles and the base material shown in Table 1, composite structures of samples a to d and f to n were prepared. A commercially available sample prepared by the ion plating method was used as the sample e, and the other samples were prepared by the aerosol deposition method.

  The basic structure of the device used for the AD method was the same as the device shown in FIG. The raw material particles, base material, gas type, and gas flow rate of each sample were as shown in Table 1, and the injection speed from the nozzle was 150 m / s or more. Further, the thickness of each of the structures was about 5 μm. The formation of the structure was performed at room temperature (around 20 ° C.).

2. Characterization of structures (Part 1)
2-1 Average crystallite size

  For sample e and sample c, the average crystallite size was calculated from the TEM image taken at a magnification of 400,000. Specifically, the average crystallite size was calculated from the average value of 15 crystallites by circular approximation using an image acquired at a magnification of 400,000 times.

  The average crystallite size calculated from the TEM image of the sample c prepared by the AD method was 9 nm.

  In sample e produced by ion plating, the average crystallite size calculated from the TEM image was 1 nm.

2-2 For the porosity measurement samples a to h, the porosity was calculated by image analysis using the image analysis software WinRoof 2015 using images acquired by a scanning electron microscope (SEM). The magnification was 5,000 times to 20,000 times. The measurement of the porosity has been conventionally used as a method for evaluating the denseness of a structure.

  As a result, the porosity of each of the samples a to h was 0.01% or less. SEM images of samples a, c, e, f and g were as shown in FIG. 12, respectively. As will be described later, the porosity measurement of these samples having different particle resistances could not identify the difference in the structure of the samples.

3. Characterization of structures (Part 2)
3-1. Measurement of hydrogen amount by D-SIMS method A sample for hydrogen amount measurement was prepared by the following method. First, two samples a to c, f, i to k, m and n were prepared. The sample size was 3 mm x 3 mm and the thickness was 3 mm. For each of the samples, one was used as a standard sample and the other was used as a measurement sample. For each sample, the surface 10a of the structure 10 was polished to have a two-dimensional average surface roughness Ra of 0.01 μm. Next, each sample was allowed to stand at room temperature of 20-25 ° C., humidity of 60% ± 10% and atmospheric pressure for 24 hours or more, and then the amount of hydrogen was measured by D-SIMS.

  Secondary ion mass spectrometry: Measurement of hydrogen amount by Dynamic-Secondary Ion Mass Spectrometry (D-SIMS method) was performed using an IMF-7f manufactured by CAMECA as an apparatus.

  The preparation of the standard sample was as follows. An evaluation sample, a standard sample for an evaluation sample having a matrix component equivalent to that of the evaluation sample, a Si single crystal, and a standard sample for a Si single crystal were prepared. Of each of the two prepared samples, one was used as an evaluation sample and the other was used as a standard sample for evaluation samples. The standard sample for the evaluation sample is obtained by injecting deuterium into a sample having a matrix component equivalent to that of the evaluation sample. At this time, deuterium was simultaneously injected into the Si single crystal, and equivalent deuterium was injected into the standard sample for the evaluation sample and the Si single crystal. Thereafter, the amount of deuterium injected into the Si single crystal was identified using a standard sample for the Si single crystal. For the standard sample for the evaluation sample, the secondary ion intensities of deuterium and constituent elements were calculated using secondary ion mass spectrometry (D-SIMS method), and the interphase sensitivity coefficient was calculated. The hydrogen amount of the evaluation sample was calculated using the inter-phase sensitivity coefficient calculated from the standard sample for the evaluation sample. About others, ISO 18114_ "Determining relative sensitivity factors from ion-implanted reference materials" (International Organization for Standardization, Geneva, 2003) was suitably referred.

  Conductive platinum (Pt) was deposited on the surface of each structure of the measurement sample and the standard sample. Cesium (Cs) ion was used as a primary ion species as a measurement condition of D-SIMS. The primary acceleration voltage was 15.0 kV, the detection area was 8 μmφ, and the measurement depth was 500 nm, 2 μm, and 5 μm.

The obtained number of hydrogen atoms per unit volume (atoms / cm ³ ) was as shown in Table 2 below.

3-2. Measurement of hydrogen amount by RBS-HFS method and p-RBS method First, for samples a, c, f, and j, the surface 10a of the structure 10 was polished to obtain a two-dimensional average surface roughness Ra of 0.01 μm. And Next, the sample was allowed to stand at room temperature of 20-25 ° C., humidity of 60% ± 10%, and atmospheric pressure for 24 hours or more, and then the amount of hydrogen (hydrogen atom concentration) was measured.

  The measurement of the amount of hydrogen was performed by combining RBS-HFS and p-RBS. As an apparatus, Pelletron 3SDH manufactured by National Electrostatics Corporation was used.

The measurement conditions of the RBS-HFS method were as follows.
Incident ion: 4He ⁺
Incident energy: 2300 KeV, incident angle: 75 °, scattering angle: 160 °, recoil angle: 30 °
Sample current: 2 nA, beam diameter: 1.5 mmφ, irradiation amount: 8 μC
In-plane rotation: None

The measurement conditions of the p-RBS method were as follows.
Incident ion: hydrogen ion (H ⁺ )
Incident energy: 1740 KeV, incident angle: 0 °, scattering angle: 160 °, recoil angle: none, sample current: 1 nA, beam diameter: 3 mmφ, irradiation amount: 19 μC
In-plane rotation: None

  The obtained hydrogen atom concentration was as shown in Table 2 below.

3-3-1. For creating samples a to n TEM observation samples, the TEM observation sample focused ion beam method (FIB method, Focused Ion Beam) was prepared by. First, each sample was cut. Then, FIB processing was performed on the structure surface of each sample. First, a carbon layer 50 was deposited on the surface of the structure of each sample. The target thickness of the carbon layer was set to about 300 nm.

  After the carbon layer was deposited, each sample was sliced using a FIB apparatus. First, a portion of the structure of each sample was cut out together with the carbon layer by irradiating a Ga ion beam around the portion to be sliced with the carbon layer facing upward. The cut-out structure was fixed to a FIB TEM sample table by a FIB pickup method using a tungsten deposition function. Next, a tungsten layer was formed by a tungsten deposition process on the carbon layer 50 and at a portion to be sliced for TEM observation. The target thickness of the tungsten layer was 500 to 600 nm. Then, the structure of each sample was shaved from both sides at the flaked portion with Ga ions, to prepare a TEM observation sample. The target thickness of the TEM observation sample at this time was set to 100 nm. The accelerating voltage at the time of FIB processing was started from the maximum voltage of 40 kV, and finally the finishing processing was performed at the minimum voltage of 5 kV. Thus, three TEM observation samples were obtained.

  Next, the upper thickness 90u of the TEM observation sample 90 was confirmed. A secondary electron image was obtained using a TEM observation sample and a scanning electron microscope (SEM), and an upper thickness of 90 u was obtained from the secondary electron image. S-5500 manufactured by HITACHI was used for SEM. The SEM observation conditions were a magnification of 200,000, an acceleration voltage of 2 kV, a scan time of 40 seconds, and an image number of 2560 * 1920 pixels. Using the scale bar of this SEM image, an upper thickness of 90 u of each TEM observation sample was obtained from an average of five measurements. Table 1 shows the upper thickness 90u of each sample. When the sample upper thickness 90u is larger than 100 ± 30 nm, the brightness Sa tends to be small, and when the sample upper thickness 90u is smaller than 100 ± 30 nm, the brightness Sa tends to be larger. For sample g, the upper thickness of the sample was 138 nm, which was larger than the specified range, that is, the luminance Sa was considered to be smaller than originally expected, but it was confirmed that the luminance was still outside the scope of the present invention.

3-3-2. TEM bright-field image photographing A bright-field image was photographed by TEM for samples a to n obtained by FIB processing. Using a transmission electron microscope H-9500 (manufactured by Hitachi High-Technologies Corporation), an acceleration voltage of 200 kV, an observation magnification of 100,000 times, and a digital / camera (OneView Camera Model 1095 / Gatan), photographing pixels 4096 × 4096 pixels, capture The image was taken at a speed of 6 fps, an exposure time of 2 sec, an image capture mode of exposure time, and a camera position bottom mount. A TEM digital black-and-white image was obtained so that the carbon layer and the tungsten layer deposited during sample preparation were included in the same field of view.

  FIG. 13 is a TEM image of each of the samples a to g, i, j, and l taken at a magnification of 100,000. Three TEM images were obtained for each TEM observation sample so as to be continuous in the horizontal direction, and a total of nine TEM images were obtained for one sample.

3-3-3. The brightness value of the image was obtained from the TEM bright-field image obtained by obtaining the brightness value and calculating the brightness Sa by image analysis using the image analysis software WinROOF2015. Specifically, as shown in FIG. 13, for each image G, the region vertical length dL is 0.5 μm and the region horizontal length dw is the image horizontal length Gw of the image G, with the vicinity of the structure surface 10a as a base point. The luminance acquisition region R was set so as to be almost the same. For each luminance acquisition region R, the luminance value for each pixel was acquired, and the luminance value was relatively corrected by setting the luminance of the tungsten layer in the region R to 0 and the luminance of the carbon layer to 255. Here, as the luminance value of the tungsten layer, the average value of the luminance values of 10,000 pixels was used in ascending order from the minimum value of the luminance value in the tungsten layer in the TEM image. Further, as the luminance value of the carbon layer, an average value of luminance values of 100,000 pixels was used in ascending order from the maximum value of the luminance value in the carbon layer. The respective average values obtained here were treated as the luminance values of the carbon layer / tungsten layer before correction.

For each of the luminance acquisition regions R, the average of the absolute value of the difference between the luminance values after correction for each pixel was calculated using the least squares method. The values obtained from the nine TEM images in this manner were averaged to obtain the luminance Sa. At this time, the total area of the luminance acquisition regions R was 6.9 μm ² or more.

  Further, as shown in FIGS. 13E, 13F, and 13G, when the interface between the surface 10a of the structure 10 and the tungsten layer 50 is not linear, the luminance acquisition region R is avoided by avoiding the region. It was set. In addition, as shown in FIG. 13E, when unevenness on the surface 10a of the structure 10 is observed, the region vertical length dL is set with the point closest to the surface 10a as a starting point.

  The obtained luminance Sa value was as shown in Table 2 described later.

3-4. Calculation of luminance Sa excluding noise component 3-3-3. In the process of acquiring the luminance value and calculating the luminance Sa by the image analysis, the luminance value of the image was acquired by setting the image analysis software WinROOF2015 in a mode for removing noise components.

  The obtained luminance Sa value was as shown in Table 2 described later.

3-5. With respect to the refractive index calculation samples a and c, the surface 10a of the structure 10 was polished so that the two-dimensional average surface roughness Ra was 0.1 μm or less and the thickness of the structure 10 was 1 μm or less.

  The refractive index was measured by reflection spectroscopy using a microspectrophotometer (OPTM-F2 manufactured by Otsuka Electronics Co., Ltd., FE-37S manufactured by Otsuka Electronics). The measurement conditions were a measurement spot size of 10 μm and a measurement wavelength range of 360 to 1100 nm.

  The analysis conditions were an analysis wavelength range of 360 to 1100 nm, and an optimization method and a least squares method were used. For each sample, the refractive index for each wavelength was as shown in Table 3 below and FIG.

As shown in Table 3 and FIG. 19, the refractive index of the structure containing the YO compound according to the present invention is higher than the conventionally known refractive index of Y ₂ O ₃ of 1.92, and the particle resistance is high. Had.

4. Structure property evaluation
4-1. For the plasma resistance evaluation samples a to n, a “standard plasma resistance test” was performed.

Specifically, in the test, an inductively coupled plasma reactive ion etching apparatus (Muc-21 Rv-Aps-Se / Sumitomo Seimitsu Kogyo) was used as a plasma etching apparatus. The plasma etching conditions were as follows: an ICP output of 1500 W as a power output, a bias output of 750 W, a mixed gas of 100 ccm of CHF ₃ gas and 10 ccm of O ₂ gas as a process gas, a pressure of 0.5 Pa, and a plasma etching time of 1 hour.

  The state of the surface 10a of the structure 10 after the plasma irradiation was photographed by SEM. They were as shown in FIG. The SEM observation conditions were a magnification of 5,000 and an acceleration voltage of 3 kV.

  Next, from the obtained SEM image, the area of the corrosion trace on the surface after plasma irradiation was calculated. The results were as shown in Table 2.

  The state of the surface 10a of the structure 10 after the plasma irradiation was photographed with a laser microscope. Specifically, a laser microscope “OLS4500 / Olympus” was used, and the objective lens was MPLAPON 100 × LEXT (numerical aperture 0.95, working distance 0.35 mm, focused spot diameter 0.52 μm, measurement area 128 × 128 μm). And the magnification was 100 times. The λc filter for removing the undulation component was set to 25 μm. The measurement was performed at three arbitrary positions, and the average value was defined as the arithmetic average height Sa. In addition, three-dimensional surface texture international standard ISO25178 was appropriately referred. The value of the arithmetic mean height Sa of the surface 10a after the plasma irradiation was as shown in Table 4.

FIG. 15 is a graph of the corrosion trace area (μm ² ) for each sample. As shown in FIG. 15, the sample formed by the aerosol deposition method generally had a smaller corrosion scar area and a better result than the sample (e) formed by ion plating.

FIG. 16 shows the relationship between the luminance Sa and the area of the corrosion mark (μm ² ) for each sample formed by the aerosol deposition method. As shown in FIG. 16, it can be seen that the corrosion mark area can be significantly reduced by setting the luminance Sa to a predetermined value or less.

  Further, as shown in FIG. 17 and Table 2, it can be seen that the particle resistance can be improved by reducing the amount of hydrogen (the number of hydrogen atoms per unit volume / hydrogen atom concentration) on the surface of the structure.

100: Composite structure, 10: Structure, 10a: Structure surface, 10u: Upper region, 10b: Lower region, 11: Gas supply unit, 12: Piping , 13 ... aerosol supply unit, 14 ... chamber, 15 ... nozzle, 16 ... stage, 17 ... drive unit, 18 ... exhaust unit, 19 ... device, 50 ...・ Carbon layer, 60 ・ ・ ・ Tungsten layer, 70 ・ ・ ・ Base, 70a ・ ・ ・ Base surface, dL ・ ・ ・ Region vertical length, dW ・ ・ ・ Region horizontal length, R ・ ・ ・ Luminance acquisition region, G: Image area, Gl: Image vertical length, Gw: Image horizontal length, L: Vertical direction, W: Horizontal direction, 90: TEM observation sample, 90h・ ・ ・ Sample height, 90u ・ ・ ・ Sample upper thickness, 90b ・ ・ ・ Sample lower thickness, 90w ・ ・ ・ Sample width, 301 ・ ・ ・ Semiconductor manufacturing equipment member, 302 ・ ・ ・ Semiconductor manufacturing equipment member, 30a ・ ・ ・ Plasma irradiation area, 30b ・ ・ ・Plasma non-irradiation area, 40: sample acquisition point for luminance Sa measurement, 31: hole, 81: primary particle, 82: secondary particle, 10c: crystallite

The standard sample is generally used in the SIMS method to normalize the signal intensity of the ion species to be analyzed with the signal intensity of the ion species including the matrix element of the sample for the purpose of canceling out the factors relating to the measurement conditions. More specifically, an evaluation sample, a standard sample for an evaluation sample having a matrix component equivalent to the evaluation sample, an Si single crystal, and a standard sample for a Si single crystal are used. The standard sample for the evaluation sample is obtained by injecting deuterium into a sample having a matrix component equivalent to that of the evaluation sample. At this time, it is assumed that deuterium is simultaneously injected into the Si single crystal, and that equivalent deuterium is injected into the standard sample for the evaluation sample and the Si single crystal. Thereafter, the amount of deuterium injected into the Si single crystal is identified using a standard sample for the Si single crystal. For the standard sample for the evaluation sample, the secondary ion intensities of deuterium and constituent elements are calculated using secondary ion mass spectrometry (D-SIMS method), and the relative sensitivity coefficient is calculated. The amount of hydrogen in the evaluation sample is calculated using the relative sensitivity coefficient calculated from the standard sample for the evaluation sample. For others, reference can be made to ISO 18114_ “Determining relative sensitivity factors from ion-implanted reference materials” (International Organization for Standardization, Geneva, 2003).

Claims (28)

A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure includes polycrystalline ceramics,
The number of hydrogen atoms per unit volume at a measurement depth of 500 nm or 2 μm measured by secondary ion mass spectrometry (Dynamic-Secondary Ion Mass Spectrometry_D-SIMS) is 7 * 10 ²¹ atoms / cm ³ or less. Is a composite structure. The composite structure according to claim 1, wherein the number of hydrogen atoms per unit volume of the structure is 5 * 10 < ²¹ > atoms / cm < ³ > or less. A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure includes polycrystalline ceramics,
Hydrogen forward scattering analysis (HFS)-A composite structure having a hydrogen atom concentration of 7 atomic% or less as measured by Rutherford backscattering spectroscopy (RBS) and proton-hydrogen forward scattering analysis (p-RBS). A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure comprises polycrystalline ceramics,
A composite structure having a luminance Sa value calculated by the following method of 19 or less:
The method for obtaining the luminance Sa is as follows:
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) preparing a digital black and white image of a bright field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
In the step (v),
For each of the luminance acquisition areas, an average of absolute values of the differences between the corrected luminance values for each of the pixels is calculated using a least squares method, and the average is defined as luminance Sa.   The composite structure according to claim 4, wherein the brightness Sa is 13 or less. A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure comprises polycrystalline ceramics,
A composite structure, wherein the luminance Sa value calculated by the following method is 10 or less:
The method for obtaining the luminance Sa is as follows:
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) obtaining a digital black-and-white image of a bright-field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
At the time of the FIB processing, a carbon layer and a tungsten layer for antistatic and sample protection are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
A noise removal using a low-pass filter is performed on the digital black-and-white image whose luminance value has been corrected, wherein a cut-off frequency in the noise removal using the low-pass filter is 1 / (10 pixels )
In the step (v),
For each of the luminance acquisition areas, an average of absolute values of the differences between the corrected luminance values for each of the pixels is calculated using a least squares method, and the average is defined as luminance Sa.   The composite structure according to claim 6, wherein the luminance Sa is 5 or less. A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure includes a polycrystalline ceramic containing Y (yttrium element) and O (oxygen element);
The refractive index at a wavelength of 400 nm to 550 nm is larger than 1.92,
The refractive index is calculated by reflection spectroscopy using a microspectrophotometer,
As measurement conditions, the measurement spot size is 10 μm, the average surface roughness Ra of the substrate surface and the composite structure surface is ≦ 0.1 μm, the thickness of the structure is ≦ 1 μm, and the measurement wavelength range is 360 to 1100 nm.
A composite structure that uses an analysis wavelength range of 360 to 1100 nm, an optimization method, and a least squares method as analysis conditions. A composite structure including a substrate and a structure provided on the substrate and having a surface,
The structure includes a polycrystalline ceramic containing Y (yttrium element) and O (oxygen element);
The refractive index is at least one of 1.99 or more at a wavelength of 400 nm, 1.96 or more at a wavelength of 500 nm, 1.94 or more at a wavelength of 600 nm, 1.93 or more at a wavelength of 700 nm, and 1.92 or more at a wavelength of 800 nm or more. The filling,
The refractive index is calculated by reflection spectroscopy using a microspectrophotometer,
As measurement conditions, the measurement spot size is 10 μm, the average surface roughness Ra of the substrate surface and the composite structure surface is ≦ 0.1 μm, the thickness of the structure is ≦ 1 μm, and the measurement wavelength range is 360 to 1100 nm.
A composite structure that uses an analysis wavelength range of 360 to 1100 nm, an optimization method, and a least squares method as analysis conditions. A method for evaluating a microstructure of a structure having a surface, including a polycrystalline ceramic,
(I) preparing a transmission electron microscope (TEM) observation sample of the structure;
(Ii) preparing a digital black and white image of a bright field image of the TEM observation sample;
(Iii) obtaining a luminance value in which color data of each pixel in the digital monochrome image is represented by a gradation value;
(Iv) correcting the luminance value;
(V) calculating a luminance Sa using the corrected luminance value,
In the step (i),
The TEM observation sample is prepared at least three from the structure,
Each of the at least three TEM observation samples is formed by using a focused ion beam method (FIB method) while suppressing processing damage.
During the FIB processing, a carbon layer and a tungsten layer are provided on the surface of the structure,
When the FIB processing direction is the vertical direction, the sample upper thickness, which is the length in the minor axis direction of the surface of the structure in a plane perpendicular to the vertical direction, is 100 ± 30 nm,
In the step (ii),
The digital black and white image is obtained for each of the at least three TEM observation samples,
Each of the digital black and white images uses a transmission electron microscope (TEM) at a magnification of 100,000 and an accelerating voltage of 200 kV, and includes the structure, the carbon layer, and the tungsten layer,
In each of the digital black-and-white images, a brightness acquisition area having an area vertical length of 0.5 μm in the vertical direction from the surface of the structure is set,
Acquiring the plurality of digital black-and-white images from each of the at least three TEM observation samples so that the total area of the luminance acquisition regions is 6.9 μm ² or more,
In the step (iv),
Regarding the brightness value, the brightness value of the carbon layer is 255, the brightness value of the tungsten layer is 0, and the brightness value after correction is relatively corrected to obtain a brightness value,
In the step (v),
For each of the luminance acquisition regions, calculate the average of the absolute value of the difference between the corrected luminance values for each pixel using the least squares method, and set the average as the luminance Sa.
Evaluation method. In the step (iv),
The method further includes the step of performing noise removal using a low-pass filter on the digital black-and-white image whose luminance value has been corrected, wherein a cut-off frequency in the noise removal using the low-pass filter is 1 / ( The evaluation method according to claim 10, wherein the number of pixels is 10 pixels.   The method of suppressing the processing damage is at least one of performing finishing processing at a low voltage of 5 kV, removing the processing damage by Ar ions, and cleaning a surface by ion milling before the TEM observation. Item 12. The evaluation method according to item 10 or 11. The sample upper thickness is obtained by a secondary electron image using a scanning electron microscope (SEM) for the TEM observation sample,
The observation conditions of the SEM were 200,000 times magnification, 2 kV acceleration voltage, 40 seconds scan time, and 2560 * 1920 pixels.
The evaluation method according to claim 10, wherein the SEM image forms a plane perpendicular to the vertical direction.   The evaluation method according to any one of claims 10 to 13, wherein the at least three TEM observation samples are obtained evenly from the surface of the structure.   The evaluation method according to any one of claims 10 to 14, wherein in the acquisition of the digital monochrome image, after adjusting the focus at a magnification of 300,000 or more, the digital monochrome image of 100,000 is acquired. . In the step (iv),
As the brightness value of the tungsten layer before correction, in the brightness value of the tungsten layer in the digital black and white image, using the average value of the brightness values of 10,000 pixels in ascending order from the minimum value,
The brightness value of the carbon layer before the correction, the brightness value of the carbon layer in the digital black and white image, using the average value of the brightness value of 100,000 pixels in order from the largest value to the largest continuously. Item 15. The evaluation method according to any one of Items 15.   The evaluation method according to any one of claims 10 to 16, wherein, in the luminance acquisition region, a region horizontal length perpendicular to the region vertical length is set to be the longest in the digital monochrome image.   When acquiring the plurality of digital monochrome images from each of the at least three TEM observation samples, the plurality of digital monochrome images are continuous in the horizontal direction perpendicular to the vertical direction of the digital monochrome image. The evaluation method according to any one of claims 10 to 17, wherein the evaluation method is performed to perform the evaluation.   The evaluation method according to any one of claims 10 to 18, wherein image analysis software is used in each of the steps (iii) to (iv).   The composite structure according to any one of claims 1 to 9, wherein an average crystallite size of the polycrystalline ceramic, calculated from a TEM image at a magnification of 400,000 to 2,000,000 times, is 3 nm or more and 50 nm or less.   The composite structure according to any one of claims 1 to 9, wherein the crystallite size is 30 nm or less.   22. The composite structure according to claim 21, wherein the crystallite size is 5 nm or more.   23. The composite structure according to any one of claims 1 to 9, 21 and 22, wherein the structure is selected from rare earth oxides, fluorides, and oxyfluorides, and mixtures thereof.   The rare earth element is at least one selected from the group consisting of Y, Sc, Yb, Ce, Pr, Eu, La, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu. A composite structure according to claim 23.   The composite structure according to any one of claims 1 to 9, 21 to 23, wherein the structure has an arithmetic mean height Sa of 0.060 or less after the reference plasma resistance test.   The composite structure according to any one of claims 1 to 9, 21 to 25, which is used in an environment where particle resistance is required.   A semiconductor manufacturing apparatus comprising the composite structure according to any one of claims 1 to 9, 21 to 26. A display manufacturing apparatus comprising the composite structure according to any one of claims 1 to 9, 21 to 26.