Ceramic sintered body

Abstract

This ceramic sintered body comprises alumina as a main component and magnesium, silicon, calcium and zirconium as secondary components. For example, the zirconium content, in terms of zirconium oxide, is 0.01-1.0 mass%.

Description

Ceramic sintered body

[0001] The embodiments of the disclosure relate to ceramic sintered bodies.

[0002] Alumina sintered bodies are suitably used as components for semiconductor manufacturing equipment. Various properties are required for alumina sintered bodies; for example, alumina sintered bodies with low dielectric loss and alumina sintered bodies with high strength are desired.

[0003] For example, an alumina sintered body with low dielectric loss is known, which contains 0.01 to 1.0 mass% of one or more elements selected from Ta, Nb, and V in terms of oxide (see, for example, International Publication No. 2019 / 026871).

[0004] A ceramic sintered body according to one embodiment contains alumina as the main component, and magnesium, silicon, calcium, and zirconium as minor components.

[0005] Figure 1 shows the composition and properties of a ceramic sintered body according to an example. Figure 2 shows the composition and properties of a ceramic sintered body according to an example. Figure 3 shows the composition and properties of a ceramic sintered body according to a comparative example.

[0006] The embodiments for carrying out the ceramic sintered body according to this disclosure (hereinafter referred to as "embodiments") will be described in detail below with reference to the drawings. The ceramic sintered body according to this disclosure is not limited by these embodiments. Each embodiment can be combined as appropriate without contradicting its content.

[0007] Alumina sintered bodies are suitably used as components for semiconductor manufacturing equipment. Various properties are required for alumina sintered bodies; for example, alumina sintered bodies with low dielectric loss and alumina sintered bodies with high strength are desired.

[0008] However, conventional technologies still have room for improvement in terms of low dielectric loss and high strength.

[0009] Therefore, there is a need for a technology that can overcome the aforementioned problems and provide ceramic sintered bodies with low dielectric loss and high strength.

[0010] The ceramic sintered body according to this embodiment is a sintered body obtained by sintering ceramic raw materials. ２ O ３ The ceramic sintered body according to this embodiment contains alumina, and also contains magnesium (Mg), silicon (Si), calcium (Ca), and zirconium (Zr) as minor components. Since the ceramic sintered body according to this embodiment contains alumina, it contains aluminum (Al) and oxygen (O) as constituent elements. Here, "alumina as the main component" means that the alumina content in the ceramic sintered body is 99.0% by mass or more. The ceramic sintered body according to this embodiment is also called an alumina sintered body. "Magnesium, silicon, calcium, and zirconium as minor components" means that magnesium, silicon, calcium, and zirconium are contained in the ceramic sintered body as components other than alumina as the main component. Each of the magnesium, silicon, calcium, and zirconium contained in the ceramic sintered body is contained as a constituent element in the ceramic sintered body.

[0011] The ceramic sintered body according to this embodiment may contain impurities other than alumina as the main component and magnesium, silicon, calcium, and zirconium as minor components. The impurities contained in the ceramic sintered body are, for example, caused by impurities contained in the ceramic raw material. Examples of impurities that may be contained in the ceramic sintered body include component elements such as sodium (Na), chromium (Cr), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), gallium (Ga), and rare earth elements such as yttrium (Y).

[0012] In the ceramic sintered body according to this embodiment, the sum of the alumina content, the magnesium content in terms of magnesium oxide, the silicon content in terms of silicon oxide, the calcium content in terms of calcium oxide, and the zirconium content in terms of zirconium oxide is 100% by mass or less.

[0013] The types and percentages of constituent elements and impurities contained in the ceramic sintered body according to this embodiment can be confirmed by elemental analysis, such as X-ray fluorescence analysis (XRF) or inductively coupled plasma (ICP) emission spectroscopy.

[0014] The alumina content is calculated by multiplying the aluminum content by the formula weight of alumina and the atomic weight of aluminum. The magnesium content in terms of magnesium oxide is calculated by multiplying the magnesium content by the formula weight of magnesia (MgO) and the atomic weight of magnesium. The silicon content in terms of silicon oxide is calculated by multiplying the silicon content by silica (SiO₂) ２ The formula weight of ) is calculated as / the atomic weight of silicon. The calcium content in terms of calcium oxide is calculated as calcium content × formula weight of calcia (CaO) / atomic weight of calcium. The zirconium content in terms of zirconium oxide is calculated as zirconium content × zirconia (ZrO) ２ It is calculated by dividing the formula weight of zirconium by the atomic weight of zirconium.

[0015] The ceramic sintered body according to this embodiment contains alumina as the main component and magnesium, silicon, calcium, and zirconium as minor components, thereby reducing the dielectric loss of the ceramic sintered body and improving its strength. More specifically, the ceramic sintered body according to this embodiment can reduce the dielectric loss of the ceramic sintered body by containing magnesium, silicon, and calcium as minor components in addition to alumina as the main component. By further containing zirconium as a minor component in addition to alumina as the main component, the ceramic sintered body according to this embodiment can appropriately promote the growth of crystal grains contained in the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. In other words, it becomes possible to appropriately reduce the occurrence of defects (voids) in the ceramic sintered body. Accordingly, it becomes possible to improve the bulk density of the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. As a result, it becomes possible to improve the strength of the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. In this way, it becomes possible to provide a ceramic sintered body with low dielectric loss and high strength.

[0016] An indicator of dielectric loss in a ceramic sintered body is, for example, the dielectric loss tangent (tanδ) of the ceramic sintered body. The dielectric loss tangent of a ceramic sintered body is measured, for example, according to the Japanese Industrial Standard JIS C2138:2007 "Electrical insulating materials - Measurement of relative permittivity and dielectric loss tangent". For example, the dielectric loss tangent of a ceramic sintered body is measured by the bridge circuit method using a Keysight E4990A impedance analyzer.

[0017] Bulk density of ceramic sintered body (g / cm³) ３ ) is measured, for example, by the Archimedes method.

[0018] One indicator of the strength of a ceramic sintered body is the three-point bending strength (MPa). The three-point bending strength of a ceramic sintered body is measured, for example, according to the Japanese Industrial Standard JIS R1601:2008 "Test Method for Room Temperature Bending Strength of Fine Ceramics". For example, the three-point bending strength of a ceramic sintered body is measured using the Autograph AG-IS tensile and compression testing machine manufactured by Shimadzu Corporation.

[0019] In the ceramic sintered body according to this embodiment, for example, the alumina content may be 99.0% by mass or more. In this case, the sum of the magnesium content in terms of magnesium oxide, the silicon content in terms of silicon oxide, the calcium content in terms of calcium oxide, and the zirconium content in terms of zirconium oxide may be, for example, 0.80% by mass or more and 0.95% by mass or less. The impurity content contained in the ceramic sintered body may be, for example, 0.05% by mass or more and 0.20% by mass or less. This makes it easier to reduce the dielectric loss of the ceramic sintered body and to improve its strength. In this way, it becomes easier to provide a ceramic sintered body with low dielectric loss and high strength.

[0020] In the ceramic sintered body according to this embodiment, for example, the alumina content may be 99.7% by mass or more. In this case, the sum of the magnesium content in terms of magnesium oxide, the silicon content in terms of silicon oxide, the calcium content in terms of calcium oxide, and the zirconium content in terms of zirconium oxide may be, for example, 0.20% by mass or more and 0.25% by mass or less. The impurity content contained in the ceramic sintered body may be, for example, 0.05% by mass or more and 0.10% by mass or less. This makes it possible to more easily reduce the dielectric loss of the ceramic sintered body and to more easily improve the strength of the ceramic sintered body. In this way, it becomes possible to more easily provide a ceramic sintered body with low dielectric loss and high strength.

[0021] In the ceramic sintered body according to the present embodiment, for example, the magnesium content may be 0.01% by mass or more and 0.84% by mass or less in terms of magnesium oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0022] In the ceramic sintered body according to the present embodiment, for example, the magnesium content may be 0.07% by mass or more and 0.08% by mass or less in terms of magnesium oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0023] In the ceramic sintered body according to the present embodiment, for example, the silicon content may be 0.01% by mass or more and 0.74% by mass or less in terms of silicon oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0024] In the ceramic sintered body according to the present embodiment, for example, the silicon content may be 0.06% by mass or more and 0.09% by mass or less in terms of silicon oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0025] In the ceramic sintered body according to the present embodiment, for example, the calcium content may be 0.01% by mass or more and 0.56% by mass or less in terms of calcium oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0026] In the ceramic sintered body according to the present embodiment, for example, the calcium content may be 0.03% by mass or more and 0.04% by mass or less in terms of calcium oxide. In this case, it becomes possible to more easily reduce the dielectric loss of the ceramic sintered body. Thus, it becomes possible to more easily provide a ceramic sintered body having a low dielectric loss and high strength.

[0027] In the ceramic sintered body according to the present embodiment, for example, the zirconium content may be 0.01% by mass or more and 1.0% by mass or less in terms of zirconium oxide. In this case, the zirconium content may be 0.01% by mass or more in terms of zirconium oxide, and in such a case, it becomes possible to more easily promote the growth of crystal grains contained in the ceramic sintered body. The zirconium content may be 1.0% by mass or less in terms of zirconium oxide, and in such a case, it becomes possible to more easily reduce excessive growth of crystal grains contained in the ceramic sintered body. Accordingly, it becomes possible to more appropriately improve the bulk density of the ceramic sintered body. As a result, it becomes possible to more easily improve the strength of the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. Thus, it becomes possible to provide a ceramic sintered body having a low dielectric loss and high strength.

[0028] In the ceramic sintered body according to this embodiment, for example, the zirconium content may be 0.01% by mass or more and 0.50% by mass or less in terms of zirconium oxide. In this case, the zirconium content may be 0.01% by mass or more in terms of zirconium oxide, and in such a case, it becomes possible to more easily promote the growth of crystal grains contained in the ceramic sintered body. The zirconium content may be 0.50% by mass or less in terms of zirconium oxide, and in such a case, it becomes possible to more easily reduce the excessive growth of crystal grains contained in the ceramic sintered body. Accordingly, it becomes possible to more appropriately improve the bulk density of the ceramic sintered body. As a result, it becomes possible to more easily improve the strength of the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. In this way, it becomes possible to provide a ceramic sintered body with low dielectric loss and high strength.

[0029] In the ceramic sintered body according to this embodiment, for example, the zirconium content may be 0.04% by mass or more and 0.10% by mass or less in terms of zirconium oxide. In this case, the zirconium content may be 0.04% by mass or more in terms of zirconium oxide, and in such a case, it becomes possible to more easily promote the growth of crystal grains contained in the ceramic sintered body. The zirconium content may be 0.10% by mass or less in terms of zirconium oxide, and in such a case, it becomes possible to more easily reduce the excessive growth of crystal grains contained in the ceramic sintered body. Accordingly, it becomes possible to more appropriately improve the bulk density of the ceramic sintered body. As a result, it becomes possible to more easily improve the strength of the ceramic sintered body without significantly increasing the dielectric loss of the ceramic sintered body. In this way, it becomes possible to provide a ceramic sintered body with low dielectric loss and high strength.

[0030] In the ceramic sintered body according to this embodiment, for example, the alumina content may be 99.0% by mass or more, the magnesium content may be 0.01% by mass or more and 0.84% ​​by mass or less in terms of magnesium oxide, the silicon content may be 0.01% by mass or more and 0.74% by mass or less in terms of silicon oxide, the calcium content may be 0.01% by mass or more and 0.56% by mass or less in terms of calcium oxide, and the zirconium content may be 0.01% by mass or more and 0.50% by mass or less in terms of zirconium oxide. In this case, it becomes easier to provide a ceramic sintered body with low dielectric loss and high strength.

[0031] In the ceramic sintered body according to this embodiment, for example, the alumina content may be 99.7% by mass or more, the magnesium content may be 0.07% by mass or more and 0.08% by mass or less in terms of magnesium oxide, the silicon content may be 0.06% by mass or more and 0.09% by mass or less in terms of silicon oxide, the calcium content may be 0.03% by mass or more and 0.04% by mass or less in terms of calcium oxide, and the zirconium content may be 0.04% by mass or more and 0.10% by mass or less in terms of zirconium oxide. In this case, it becomes possible to more easily provide a ceramic sintered body with low dielectric loss and high strength.

[0032] The ceramic sintered body according to this embodiment can be used, for example, as a material for components that have low dielectric loss and high strength. The ceramic sintered body according to this embodiment can be used, for example, as a component included in semiconductor manufacturing equipment. Examples of such components include exposure stages and process chamber components included in plasma processing equipment used for etching semiconductor substrates.

[0033] The ceramic sintered body according to the present embodiment is manufactured, for example, according to a known Bayer method, an ammonium aluminum carbonate hydroxide (AACH) method, or the like. For example, the ceramic sintered body according to the present embodiment is manufactured according to the Bayer method as described below.

[0034] First, as ceramic raw materials, alumina (Al ２ O ３ ), powder of magnesium compound such as magnesium oxide (MgO) or magnesium hydroxide (Mg(OH) ２ ), powder of silicon dioxide (SiO ２ ), powder of calcium compound such as calcium oxide (CaO), calcium hydroxide (Ca(OH) ２ ), or calcium carbonate (CaCO ３ ), and powder of zirconium oxide (ZrO ２ ) are prepared. The powder of magnesium compound, silica powder, powder of calcium compound, and zirconium oxide powder function as sintering aids when sintering alumina powder.

[0035] Next, a predetermined amount of alumina powder, a predetermined amount of magnesium compound powder, a predetermined amount of silica powder, a predetermined amount of calcium compound powder, and a predetermined amount of zirconia powder are mixed to obtain a mixed powder. The amount of each powder is determined in consideration of the design values of the contents of alumina, magnesium, silicon, calcium, and zirconium in the ceramic sintered body and the purity of each powder. A predetermined amount of water is added to the obtained mixed powder, and the obtained mixture is wet pulverized by a pulverizer to obtain a primary slurry.

[0036] Next, after adding a dispersant to the obtained primary slurry, the obtained slurry is wet pulverized. Here, as the dispersant, for example, an ammonium polyacrylate (PAA) solution or the like can be used. The dispersant is added, for example, at a ratio of 0.02 parts by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the powder of the ceramic raw material which is the solid content in the primary slurry.

[0037] Next, a secondary slurry is obtained by adding and mixing an organic binder to the obtained slurry. Examples of organic binders include aqueous solutions of polyvinyl alcohol, aqueous solutions of acrylic resin, and aqueous solutions of polyethylene glycol. The amount of water contained in the secondary slurry is, for example, 50 parts by mass or more and 100 parts by mass or less per 100 parts by mass of the ceramic raw material powder contained in the secondary slurry.

[0038] Next, the obtained secondary slurry is spray-dried using a spray dryer to obtain granules. Here, the rotation speed of the disk to which the secondary slurry is sprayed is, for example, between 5,000 revolutions per minute (rpm) and 10,000 revolutions per minute.

[0039] Next, the obtained granules are molded using a press to obtain a molded body with a predetermined shape. The molding pressure in the press is, for example, 50 MPa to 170 MPa. The obtained molded body is fired at a temperature of 1450°C to 1600°C to obtain a ceramic sintered body. Instead of molding with a press, cold isostatic pressing (CIP) molding may be used to produce the molded body.

[0040] Next, if necessary, the obtained ceramic sintered body may be ground, for example, using a surface grinding machine. For example, the ceramic sintered body may be ground using a #200 grit grinding wheel, or the ceramic sintered body may be finished using a #400 grit grinding wheel.

[0041] The embodiments of this disclosure will be described below in detail. This disclosure is not limited to the embodiments shown below.

[0042] (Ceramic sintered body according to the example) First, a predetermined amount of alumina powder, a predetermined amount of magnesium compound powder, a predetermined amount of silica powder, a predetermined amount of calcium compound powder, and a predetermined amount of zirconia powder were mixed to obtain a mixed powder. A predetermined amount of water was added to the obtained mixed powder, and the resulting mixture was wet-ground using a pulverizer to obtain a primary slurry.

[0043] Next, an ammonium polyacrylate (PAA) solution was added to the obtained primary slurry as a dispersant, and then the resulting slurry was wet-milled.

[0044] Next, a secondary slurry was obtained by adding and mixing an organic binder to the resulting slurry.

[0045] Next, the obtained secondary slurry was spray-dried using a spray dryer to obtain granules.

[0046] Next, the obtained granules were molded using a press to produce a molded body. The obtained molded body was then fired to produce a ceramic sintered body. In this way, ceramic sintered bodies according to the examples of sample No. 1 to sample No. 80 were obtained.

[0047] Next, the bulk density (g / cm³) of the ceramic sintered bodies of the examples No. 1 to No. 80 was determined by the Archimedes method. ３ ) was measured.

[0048] Next, the three-point bending strength (MPa) of ceramic sintered bodies according to the Japanese Industrial Standard JIS R1601:2008 "Test Method for Room Temperature Bending Strength of Fine Ceramics" was measured for examples No. 1 to No. 50. Specifically, the three-point bending strength of the ceramic sintered bodies was measured using a Shimadzu Corporation Autograph AG-IS tensile and compression testing machine.

[0049] Next, the dielectric loss tangent (tanδ) of the ceramic sintered bodies according to the Japanese Industrial Standard JIS C2138:2007 "Electrical insulating materials - Measurement of relative permittivity and dielectric loss tangent" was measured for the examples of sample No. 1 to No. 50. Specifically, the dielectric loss tangent of the ceramic sintered bodies was measured using the bridge circuit method with a Keysight E4990A impedance analyzer. The frequency of the AC electric field applied to the ceramic sintered bodies was 400 kHz.

[0050] Figures 1 and 2 show the composition and properties of ceramic sintered bodies according to the examples. Figures 1 and 2 show the composition and properties of ceramic sintered bodies according to the examples from sample No. 1 to sample No. 80. Al ２ O ３The content (mass%) of SiO indicates the alumina content. The MgO content (mass%) indicates the magnesium content in terms of magnesium oxide. ２ The content (mass%) of ZrO indicates the silicon content in terms of silicon oxide. The content (mass%) of CaO indicates the calcium content in terms of calcium oxide. ２ The content (mass%) indicates the zirconium content in terms of zirconium oxide. Bulk density (g / cm³) ３ ) is the bulk density (g / cm³) of the ceramic sintered body. ３ The three-point bending strength (MPa) indicates the three-point bending strength (MPa) of the ceramic sintered body. tanδ indicates the dielectric loss tangent of the ceramic sintered body.

[0051] As shown in Figure 1, the alumina content in the ceramic sintered bodies of Examples No. 1 to No. 50 was 99.7% by mass. The MgO content (by mass%) in the ceramic sintered bodies of Examples No. 1 to No. 50 was 0.01% by mass or more and 0.84% ​​by mass or less. The SiO content in the ceramic sintered bodies of Examples No. 1 to No. 50 ２ The content (mass%) of was 0.01% by mass or more and 0.74% by mass or less. The CaO content (mass%) in the ceramic sintered bodies according to the examples of sample No. 1 to sample No. 50 was 0.01% by mass or more and 0.56% by mass or less.

[0052] ZrO in ceramic sintered bodies according to the examples of sample No. 1 to sample No. 10 ２ The content (mass%) of was 0.02 mass%. ZrO in ceramic sintered bodies according to examples No. 11 to No. 20 ２ The content (mass%) of was 0.04 mass%. ZrO in ceramic sintered bodies according to examples No. 21 to No. 30 ２ The content (mass%) of was 0.06 mass%. ZrO in ceramic sintered bodies according to examples No. 31 to No. 40 ２The content (mass%) of was 0.08 mass%. ZrO in ceramic sintered bodies according to examples No. 41 to No. 50 ２ The content (mass%) of was 0.10 mass%. Thus, the ZrO content in the ceramic sintered bodies according to the examples of Sample No. 1 to Sample No. 50 was 0.10 mass%. ２ The content (mass%) was between 0.01% by mass and 1.0% by mass, more specifically, between 0.01% by mass and 0.50% by mass.

[0053] As shown in Figure 2, the alumina content in the ceramic sintered bodies of Examples No. 51 to No. 80 was 95.0% by mass to 99.2% by mass. The MgO content (by mass%) and SiO content in the ceramic sintered bodies of Examples No. 51 to No. 80 are also shown. ２ The content (mass%) of ZrO in the ceramic sintered bodies according to the examples of Sample No. 51 to Sample No. 80 was as shown in Figure 2. ２ The content (mass%) was 0.40 mass%.

[0054] (Ceramic sintered body according to comparative example) First, a predetermined amount of alumina powder, a predetermined amount of magnesium compound powder, a predetermined amount of silica powder, and a predetermined amount of calcium compound powder were mixed to obtain a mixed powder. A predetermined amount of water was added to the obtained mixed powder, and the resulting mixture was wet-ground using a pulverizer to obtain a primary slurry.

[0055] Next, an ammonium polyacrylate (PAA) solution was added to the obtained primary slurry as a dispersant, and then the resulting slurry was wet-milled.

[0056] Next, a secondary slurry was obtained by adding and mixing an organic binder to the resulting slurry.

[0057] Next, the obtained secondary slurry was spray-dried using a spray dryer to obtain granules.

[0058] Next, the obtained granules were molded using a press to produce a molded body. The obtained molded body was then fired to produce a ceramic sintered body. In this way, ceramic sintered bodies corresponding to comparative examples No. 81 to No. 94 were obtained.

[0059] Next, the bulk density (g / cm³) of the ceramic sintered bodies of comparative examples No. 81 to No. 94 was measured in the same manner as the measurement of the bulk density of the ceramic sintered bodies in the examples. ３ Next, the three-point bending strength (MPa) of the comparative examples, from sample No. 81 to sample No. 94, was measured in the same manner as the measurement of the three-point bending strength of the ceramic sintered body according to the example. Next, the dielectric loss tangent tanδ of the comparative examples, from sample No. 81 to sample No. 94, was measured in the same manner as the measurement of the dielectric loss tangent of the ceramic sintered body according to the example.

[0060] Figure 3 shows the composition and properties of the ceramic sintered bodies related to the comparative examples. In Figure 3, the composition and properties of the ceramic sintered bodies related to the comparative examples from sample No. 81 to sample No. 94 are shown. Al in Figure 3 ２ O ３ Content (mass%) of SiO ２ The content (mass%) of ZrO, the content (mass%) of CaO, and ZrO ２ Content (mass%), bulk density (g / cm³) ３ The three-point bending strength (MPa) and tanδ are the same as those shown in Figures 1 and 2, respectively.

[0061] As shown in Figure 3, the alumina content in the comparative examples of samples No. 81 to No. 94 was 99.7% by mass. The MgO content (by mass%) in the comparative examples of samples No. 81 to No. 94 was 0.01% by mass or more and 0.84% ​​by mass or less. The SiO content in the comparative examples of samples No. 81 to No. 94 ２The content (mass%) of was 0.01% by mass or more and 0.74% by mass or less. The CaO content (mass%) in the ceramic sintered bodies of comparative examples from sample No. 81 to sample No. 94 was 0.01% by mass or more and 0.56% by mass or less.

[0062] ZrO in ceramic sintered bodies related to comparative examples of samples No. 81 to No. 94 ２ The content (mass%) was 0.00 mass%.

[0063] As shown in Figures 1, 2, and 3, it was confirmed that ceramic sintered bodies containing alumina as the main component and magnesium, silicon, and calcium as minor components tend to improve in bulk density and three-point bending strength without significantly increasing the dielectric loss tangent of the ceramic sintered body by further adding zirconium as a minor component.

[0064] As shown in Figures 1, 2, and 3, ZrO in a ceramic sintered body containing alumina as the main component and magnesium, silicon, and calcium as minor components. ２ We were able to confirm that increasing the content of [substance name] tends to further improve the bulk density and three-point bending strength of the ceramic sintered body without significantly increasing the dielectric loss tangent of the ceramic sintered body.

[0065] As shown in Figures 1, 2, and 3, it was confirmed that when the ceramic sintered body contains alumina as the main component and magnesium, silicon, calcium, and zirconium as minor components, and the zirconium content is 0.01% by mass or more and 1.0% by mass or less in terms of zirconium oxide, it has excellent properties. As shown in Figures 1 and 2, Al ２ O ３ When the content of is 98.6% by mass or more, it was confirmed that the ceramic sintered body has excellent properties. In particular, as shown in Figure 1, Al ２ O ３The content of is 99.7% by mass, the content of MgO is 0.07% by mass or more and 0.08% by mass or less, and SiO ２ The content of is 0.06% by mass or more and 0.09% by mass or less, and the content of CaO is 0.03% by mass or more and 0.04% by mass or less, and ZrO ２ When the content of is between 0.04% by mass and 0.10% by mass, it was confirmed that there is a tendency to further improve the bulk density and three-point bending strength of the ceramic sintered body without significantly increasing the dielectric loss tangent of the ceramic sintered body.

[0066] <Notes> (1) A ceramic sintered body containing alumina as the main component, and magnesium, silicon, calcium, and zirconium as minor components. For example, the zirconium content is 0.01% by mass or more and 1.0% by mass or less in terms of zirconium oxide. (2) The ceramic sintered body according to (1), wherein the alumina content is 99.0% by mass or more. (3) The ceramic sintered body according to (2), wherein the alumina content is 99.7% by mass or more. (4) The ceramic sintered body according to any one of (1) to (3), wherein the magnesium content is 0.01% by mass or more and 0.84% ​​by mass or less in terms of magnesium oxide. (5) The ceramic sintered body according to (4), wherein the magnesium content is 0.07% by mass or more and 0.08% by mass or less in terms of magnesium oxide. (6) The ceramic sintered body according to any one of (1) to (5), wherein the silicon content is 0.01% by mass or more and 0.74% by mass or less in terms of silicon oxide. (7) The ceramic sintered body according to (6), wherein the silicon content is 0.06% by mass or more and 0.09% by mass or less in terms of silicon oxide. (8) The ceramic sintered body according to any one of (1) to (7), wherein the calcium content is 0.01% by mass or more and 0.56% by mass or less in terms of calcium oxide. (9) The ceramic sintered body according to (8), wherein the calcium content is 0.03% by mass or more and 0.04% by mass or less in terms of calcium oxide. (10) The ceramic sintered body according to any one of (1) to (9), wherein the zirconium content is 0.01% by mass or more and 0.50% by mass or less in terms of zirconium oxide. (11) The ceramic sintered body according to (10), wherein the zirconium content is 0.04% by mass or more and 0.10% by mass or less in terms of zirconium oxide.

[0067] Further effects and modifications can be readily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents.

Claims

1. A ceramic sintered body containing alumina as the main component, and magnesium, silicon, calcium, and zirconium as minor components, wherein the zirconium content is 0.01% by mass or more and 1.0% by mass or less in terms of zirconium oxide.

2. The ceramic sintered body according to claim 1, wherein the alumina content is 99.0% by mass or more.

3. The ceramic sintered body according to claim 2, wherein the alumina content is 99.7% by mass or more.

4. The ceramic sintered body according to any one of claims 1 to 3, wherein the magnesium content is 0.01% by mass or more and 0.84% ​​by mass or less in terms of magnesium oxide.

5. The ceramic sintered body according to claim 4, wherein the magnesium content is 0.07% by mass or more and 0.08% by mass or less in terms of magnesium oxide.

6. The ceramic sintered body according to any one of claims 1 to 5, wherein the silicon content is 0.01% by mass or more and 0.74% by mass or less in terms of silicon oxide.

7. The ceramic sintered body according to claim 6, wherein the silicon content is 0.06% by mass or more and 0.09% by mass or less in terms of silicon oxide.

8. The ceramic sintered body according to any one of claims 1 to 7, wherein the calcium content is 0.01% by mass or more and 0.56% by mass or less in terms of calcium oxide.

9. The ceramic sintered body according to claim 8, wherein the calcium content is 0.03% by mass or more and 0.04% by mass or less in terms of calcium oxide.

10. The ceramic sintered body according to any one of claims 1 to 9, wherein the zirconium content is 0.01% by mass or more and 0.50% by mass or less in terms of zirconium oxide.

11. The ceramic sintered body according to claim 10, wherein the zirconium content is 0.04% by mass or more and 0.10% by mass or less in terms of zirconium oxide.