One embodiment of the present invention discloses an electrostatic chuck made of an aluminum nitride sintered body, wherein the aluminum nitride sintered body comprises aluminum nitride and a composite oxide formed along the grain boundaries of the aluminum nitride, wherein the composite oxide comprises at least two kinds of rare earth metals which have a solid-solution relationship with each other, and wherein the composite oxide comprises a collection area having a higher oxygen content than a surrounding area.

Silicon particles for active materials and electro-chemical cells are provided. The active materials comprising silicon particles described herein can be utilized as an electrode material for a battery. In certain embodiments, the composite material includes greater than 0% and less than about 90% by weight of silicon particles. The silicon particles have an average particle size between about 0.1 μm and about 30 μm and a surface including nanometer-sized features. The composite material also includes greater than 0% and less than about 90% by weight of one or more types of carbon phases. At least one of the one or more types of carbon phases is a substantially continuous phase.

A refractory article includes a body having a first portion defining at least a portion of a first exterior surface of the body, the first portion including a carbide, and further including a second portion defining at least a portion of a second exterior surface of the body opposite the first exterior surface, the second portion including an oxide, and a thermal conductivity difference (ΔTC) of at least 10 W/mK between the first exterior surface and the second exterior surface, and an average Shell Temperature of not greater than 400° C.

A composite sintered body, wherein the composite sintered body consists of ceramic composite sintered body, the ceramic composite sintered body comprises aluminum oxide as a main phase, and silicon carbide as a sub-phase, in which the composite sintered body has mullite in crystal grains of the aluminum oxide.

According to an embodiment, a silicon nitride sintered body includes silicon nitride crystal grains and a grain boundary phase, and in a case where Raman spectroscopy of a 20 μm×20 μm region in a central cross section of the silicon nitride sintered body is performed, two or more peaks are detected in ranges of 780 cm.sup.−1 to 810 cm.sup.−1 and 1340 cm.sup.−1 to 1370 cm.sup.−1, and four to six peaks are detected in ranges of 170 cm.sup.−1 to 190 cm.sup.−1, 607 cm.sup.−1 to 627 cm.sup.−1, 720 cm.sup.−1 to 740 cm.sup.−1, and 924 cm.sup.−1 to 944 cm.sup.−1.

Provided is a composite sintered body for an electrostatic chuck, which is not easily broken even if it is exposed to high-power plasma. Further, provided are an electrostatic chuck device using such a composite sintered body for an electrostatic chuck and a method of manufacturing a composite sintered body for an electrostatic chuck. The composite sintered body for an electrostatic chuck is a composite sintered body including an insulating ceramic and silicon carbide, in which crystal grains of the silicon carbide are dispersed in at least one selected from the group consisting of a crystal grain boundary and a crystal grain of a main phase formed by sintering crystal grains of the insulating ceramic.

Silicon particles for active materials and electro-chemical cells are provided. The active materials comprising silicon particles described herein can be utilized as an electrode material for a battery. In certain embodiments, the composite material includes greater than 0% and less than about 90% by weight of silicon particles. The silicon particles have an average particle size between about 0.1 μm and about 30 μm and a surface including nanometer-sized features. The composite material also includes greater than 0% and less than about 90% by weight of one or more types of carbon phases. At least one of the one or more types of carbon phases is a substantially continuous phase.

Silicon particles for active materials and electro-chemical cells are provided. The active materials comprising silicon particles described herein can be utilized as an electrode material for a battery. In certain embodiments, the composite material includes greater than 0% and less than about 90% by weight of silicon particles. The silicon particles have an average particle size between about 0.1 μm and about 30 μm and a surface including nanometer-sized features. The composite material also includes greater than 0% and less than about 90% by weight of one or more types of carbon phases. At least one of the one or more types of carbon phases is a substantially continuous phase.

The present application relates to a magnesium oxide based dielectric ceramics with ultrahigh dielectric breakdown strength and a preparation method thereof. The composition of the magnesium oxide based dielectric ceramic material comprises: (1−x)MgO—xAl.sub.2O.sub.3, wherein 0<x≤0.12 and x is a mole percentage. The material has a specific composite structure with magnesium aluminate spinel acting as a second phase surrounding a principal crystalline phase, MgO.

A refractory article includes a body having a first portion defining at least a portion of a first exterior surface of the body, the first portion including a carbide, and further including a second portion defining at least a portion of a second exterior surface of the body opposite the first exterior surface, the second portion including an oxide, and a thermal conductivity difference (ΔTC) of at least 10 W/mK between the first exterior surface and the second exterior surface, and an average Shell Temperature of not greater than 400° C.