Abstract: A lanthanum boride sintered body 10 includes a phase 16 including lanthanum and silicon at grain boundaries 14 between crystal grains 12 of lanthanum boride. In this lanthanum boride sintered body 10, the phase 16 exists in various configurations such as a phase 16a present at a triple point of grain boundary 14, and a phase 16b present along the grain boundary 14. This phase 16 is based on a lanthanum silicide (represented by the composition formula LaSix (0<x?2)). The lanthanum boride sintered body 10 is fabricated through a sintering step of sintering a lanthanum boride green compact by press-free sintering in an inert atmosphere or under vacuum in the presence of a silicon-containing material around and/or within the green compact. The lanthanum boride sintered body 10 having this structure exhibits a relative density of not less than 92%, and more preferably not less than 94%.

Abstract: A manufacturing method of a sintered ceramic body mixes barium silicate with aluminum oxide, a glass material, and an additive oxide to prepare a material mixture, molds the material mixture and fires the molded object. The barium silicate is monoclinic and has an average particle diameter in a range of 0.3 ?m to 1 ?m and a specific surface area in a range of 5 m2/g to 20 m2/g. The aluminum oxide has an average particle diameter in a range of 0.4 ?m to 10 ?m, a specific surface area in a range of 0.8 m2/g to 8 m2/g. A volume ratio of the aluminum oxide to the barium silicate is in a range of 10% by volume to 25% by volume.

Abstract: A manufacturing method of a sintered ceramic body mixes barium silicate with aluminum oxide, a glass material, and an additive oxide to prepare a material mixture, molds the material mixture and fires the molded object. The barium silicate is monoclinic and has an average particle diameter in a range of 0.3 ?m to 1 ?m and a specific surface area in a range of 5 m2/g to 20 m2/g. The aluminum oxide has an average particle diameter in a range of 0.4 ?m to 10 ?m, a specific surface area in a range of 0.8 m2/g to 8 m2/g. A volume ratio of the aluminum oxide to the barium silicate is in a range of 10% by volume to 25% by volume.

Abstract: A ceramic material mainly contains magnesium, aluminum, oxygen, and nitrogen, in which the ceramic material has a magnesium-aluminum oxynitride phase serving as a main phase, wherein XRD peaks of the magnesium-aluminum oxynitride phase measured with CuK? radiation appear at at least 2?=47 to 50°.

Abstract: A ceramic material according to the present invention mainly contains magnesium, aluminum, oxygen, and nitrogen, the ceramic material has the crystal phase of a MgO—AlN solid solution in which aluminum nitride is dissolved in magnesium oxide, the crystal phase serving as a main phase. Preferably, XRD peaks corresponding to the (200) and (220) planes of the MgO—AlN solid solution measured with CuK? radiation appear at 2?=42.9 to 44.8° and 62.3 to 65.2°, respectively, the XRD peaks being located between peaks of cubic magnesium oxide and peaks of cubic aluminum nitride. More preferably, the XRD peak corresponding to the (111) plane appears at 2?=36.9 to 39°, the XRD peak being located between a peak of cubic magnesium oxide and a peak of cubic aluminum nitride.

Abstract: Electrostatic chucks (1A to 1F) are provided with: susceptors (11A to 11F) having an attracting surface (11a) that attracts and holds semiconductors; and electrostatic chuck electrodes (4) that are embedded in the susceptors. The susceptors are provided with plate-shape bodies (3) and surface corrosion-resistant layers (2) that face the attracting surface. The surface corrosion-resistant layer (2) is made from a ceramic material having magnesium, aluminum, oxygen and nitrogen as main components, the ceramic material having, as a main phase, an MgO—AlN solid solution crystal phase obtained by dissolving aluminum nitride in magnesium oxide.

Abstract: An electrostatic chuck 1A includes a susceptor 11A having an adsorption face 11a of adsorbing a semiconductor, and an electrostatic chuck electrode 4 embedded in the susceptor. The susceptor 11A includes a plate shaped main body 3 and a surface corrosion resistant layer 2 including the adsorption face 2. The surface corrosion resistant layer 2 is made of a ceramic material comprising magnesium, aluminum, oxygen and nitrogen as main components. The ceramic material comprises a main phase comprising magnesium-aluminum oxynitride phase exhibiting an XRD peak at least in 2?=47 to 50° by CuK? X-ray.

Abstract: A heating apparatus 11A includes a susceptor having a heating face 12a of heating a semiconductor. The susceptor includes a plate shaped main body 13 and a surface corrosion resistant layer 14 including the heating face. The surface corrosion resistant layer 14 is made of a ceramic material comprising magnesium, aluminum, oxygen and nitrogen as main components. The ceramic material comprises a main phase comprising magnesium-aluminum oxynitride phase exhibiting an XRD peak at least in 2?=47 to 50° by CuK? X-ray.

Abstract: A heating apparatus 1A includes a susceptor part 9A having a heating face 9a of heating a semiconductor W, and a ring shaped part 6A provided in the outside of the heating face 9a. The ring shaped part 6A is composed of a ceramic material comprising magnesium, aluminum, oxygen and nitrogen as main components. The ceramic material comprises a main phase comprising magnesium-aluminum oxynitride phase exhibiting an XRD peak at least in 2?=47 to 50° taken by using CuK? ray.

Abstract: An electrostatic chuck is provided with a ceramic substrate 12 in which an electrode 14 is embedded, an electrode terminal 14a exposed at the bottom of a concave portion 16 disposed on the back surface of the ceramic substrate 12, a power feed member 20 to supply an electric power to the electrode 14, and a joining layer 22 to connect this power feed member 20 to the ceramic substrate 12. The joining layer 22 is formed by using a AuGe based alloy, a AuSn based alloy, or a AuSi based alloy. The ceramic substrate 12 and the power feed member 20 are selected in such a way that the thermal expansion coefficient difference D calculated by subtracting the thermal expansion coefficient of the ceramic substrate 12 from the thermal expansion coefficient of the power feed member 20 satisfies ?2.2?D?6 (unit: ppm/K).

Abstract: A ceramic material mainly contains magnesium, aluminum, oxygen, and nitrogen, in which the ceramic material has a magnesium-aluminum oxynitride phase serving as a main phase, wherein XRD peaks of the magnesium-aluminum oxynitride phase measured with CuK? radiation appear at at least 2?=47 to 50°.

Abstract: A ceramic material according to the present invention mainly contains magnesium, aluminum, oxygen, and nitrogen, the ceramic material has the crystal phase of a MgO—AlN solid solution in which aluminum nitride is dissolved in magnesium oxide, the crystal phase serving as a main phase. Preferably, XRD peaks corresponding to the (200) and (220) planes of the MgO—AlN solid solution measured with CuK? radiation appear at 2?=42.9 to 44.8° and 62.3 to 65.2°, respectively, the XRD peaks being located between peaks of cubic magnesium oxide and peaks of cubic aluminum nitride. More preferably, the XRD peak corresponding to the (111) plane appears at 2?=36.9 to 39°, the XRD peak being located between a peak of cubic magnesium oxide and a peak of cubic aluminum nitride.

Abstract: An aluminum oxide sintered product including a layer phase containing a rare-earth element and fluorine among grains of aluminum oxide serving as a main component, or a phase containing a rare-earth element and fluorine along edges of grains of aluminum oxide serving as a main component. The product includes a phase containing a rare-earth element and a fluorine element among grains of aluminum oxide, the phase not being in the form of localized dots but in the form of line segments, when viewed in an SEM image. The product can be readily adjusted to have a volume resistivity in the range of 1×1013 to 1×1016 ?·cm, the volume resistivity being calculated from a current value after the lapse of 1 minute from the application of a voltage of 2 kV/mm to the aluminum oxide sintered product at room temperature.

Abstract: An aluminum oxide sintered body is provided, including europium and nitrogen, and plate-like crystals having peaks coinciding with EuAl12O19 in an X-ray diffraction profile are dispersed over a whole sintered body. Such an aluminum oxide sintered body can be obtained by forming a mixed powder containing an alumina powder, a europium compound powder and an aluminum nitride powder into a green body having a predetermined shape, and sintering the green body under a non-oxidizing atmosphere.

Abstract: The aluminum-nitride-based composite material according to the present invention is an aluminum-nitride-based composite material that is highly pure with the content ratios of transition metals, alkali metals, and boron, respectively as low as 1000 ppm or lower, has AlN and MgO constitutional phases, and additionally contains at least one selected from the group consisting of a rare earth metal oxide, a rare earth metal-aluminum complex oxide, an alkali earth metal-aluminum complex oxide, a rare earth metal oxyfluoride, calcium oxide, and calcium fluoride, wherein the heat conductivity is in the range of 40 to 150 W/mK, the thermal expansion coefficient is in the range of 7.3 to 8.4 ppm/° C., and the volume resistivity is 1×1014 ?·cm or higher.

Abstract: The aluminum-nitride-based composite material according to the present invention is an aluminum-nitride-based composite material that is highly pure with the content ratios of transition metals, alkali metals, and boron, respectively as low as 1000 ppm or lower, has AlN and MgO constitutional phases, and additionally contains at least one selected from the group consisting of a rare earth metal oxide, a rare earth metal-aluminum complex oxide, an alkali earth metal-aluminum complex oxide, a rare earth metal oxyfluoride, calcium oxide, and calcium fluoride, wherein the heat conductivity is in the range of 40 to 150 W/mK, the thermal expansion coefficient is in the range of 7.3 to 8.4 ppm/° C., and the volume resistivity is 1×1014 ?·cm or higher.

Abstract: A method for manufacturing an alumina sintered body of the present invention comprises: (a) forming a mixed powder containing at least Al2O3 and MgF2 or a mixed powder containing Al2O3, MgF2, and MgO into a compact having a predetermined shape; and (b) performing hot-press sintering of the compact in a vacuum atmosphere or a non-oxidizing atmosphere to form an alumina sintered body, in which when a amount of MgF2 to 100 parts by weight of Al2O3 is represented by X (parts by weight), and a hot-press sintering temperature is represented by Y (° C.), the hot-press sintering temperature is set to satisfy the following equations (1) to (4) 1,120?Y?1,300??(1) 0.15?X?1.89??(2) Y??78.7X+1,349??(3) Y??200X+1,212??(4).

Abstract: The aluminum-nitride-based composite material according to the present invention is an aluminum-nitride-based composite material that is highly pure with the content ratios of transition metals, alkali metals, and boron, respectively as low as 1000 ppm or lower, has AlN and MgO constitutional phases, and additionally contains at least one selected from the group consisting of a rare earth metal oxide, a rare earth metal-aluminum complex oxide, an alkali earth metal-aluminum complex oxide, a rare earth metal oxyfluoride, calcium oxide, and calcium fluoride, wherein the heat conductivity is in the range of 40 to 150 W/mK, the thermal expansion coefficient is in the range of 7.3 to 8.4 ppm/° C., and the volume resistivity is 1×1014 ?·cm or higher.

Abstract: A method for manufacturing cordierite ceramics is provided, including forming and heating a cordierite-forming raw material containing ?-alumina. The degree of orientation, expressed by (I006/(I300+I006), where Ihkl is height of X-ray diffraction intensity of an hkl-face of an ?-alumina crystal, by X-ray diffraction measurement of an ?-alumina crystal in a formed article of the raw material for forming cordierite is 0.10 or more.

Abstract: A method of producing cordierite ceramic where the degree of stacking faults and the particle diameter of kaolinite used as a component of a cordierite-forming raw material are appropriately adjusted so that microcracks having an average width of 0.3 ?m or more are introduced into the resulting cordierite ceramic to produce a high-quality cordierite ceramic that includes a cordierite crystal oriented in a specific direction and has a porosity of 25% or more and a coefficient of thermal expansion of 0.30×10?6/° C. or less.