An electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C. The top surface may be sapphire. The top surface is attached to the lower portion of the electrostatic chuck using a braze layer able to withstand corrosive processing chemistries. A method of manufacturing an electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C.

A ceramic structure of the present disclosure is provided with: a first member made of a single crystal of sapphire or an yttrium aluminum composite oxide; and a second member in contact with the first member, the second member being made of ceramic containing an aluminum oxide or an yttrium aluminum composite oxide as a principal component, wherein, of crystal grains constituting the second member, contact grains of the second member, which are grains in contact with the first member, include a first curved surface part that is convex toward the first member.

A ceramic structure of the present disclosure is provided with: a first member made of a single crystal of sapphire or an yttrium aluminum composite oxide; and a second member in contact with the first member, the second member being made of ceramic containing an aluminum oxide or an yttrium aluminum composite oxide as a principal component, wherein, of crystal grains constituting the second member, contact grains of the second member, which are grains in contact with the first member, include a first curved surface part that is convex toward the first member.

The present invention discloses a dielectric ceramic formula enabling one to obtain a multilayer ceramic capacitor by alternatively stacking the ceramic dielectric layers and base metal internal electrodes. The dielectric ceramic composition comprises a primary ingredient:

[(Na.sub.1-xK.sub.x).sub.sA.sub.1-s].sub.m[(Nb.sub.1-yTa.sub.y).sub.uB1.sub.vB2.sub.w)]O.sub.3

wherein:
A is at least one selected from the alkaline-earth element group of Mg, Ca, Sr, and Ba;
B1 is at least one selected from the group of Ti, Zr, Hf and Sn;
B2 is at least one selected from transition metal elements;
and wherein:
x, y, s, u, v, and w are molar fractions of respective elements, and m is the molar ratio of [(Na.sub.1-xK.sub.x).sub.sA.sub.1-s] and [(Nb.sub.1-yTa.sub.y).sub.uB1.sub.vB2.sub.w)]. They are in the following respective range:
0.93≤m≤1.07;
0.7≤s≤1.0;
0.00≤x≤0.05; 0.00≤y≤0.65;
0.7≤u≤1.0; 0.0≤v≤0.3; 0.001≤w≤0.100;
a first sub-component composes of at least one selected from the rare-earth compound,
wherein the rare-earth element is no more than 10 mol % parts with respect to the main component; and
a second sub-component composes a compound with low melting temperature to assist the ceramic sintering process, said frit, which is Li free and could be at least one selected from fluorides, silicates, borides, and oxides. The content of frit is within the range of 0.01 mol % to 15.00 mol % parts with respect to the main component.

In some examples, a method may include depositing, from a slurry comprising particles including silicon metal, a bond coat precursor layer including the particles comprising silicon metal directly on a ceramic matrix composite substrate. The method also may include locally heating the bond coat precursor layer to form a bond coat comprising silicon metal. Additionally, the method may include forming a protective coating on the bond coat. In some examples, an article may include a ceramic matrix composite substrate, a bond coat directly on the substrate, and a protective coating on the bond coat. The bond coat may include silicon metal and a metal comprising at least one of Zr, Y, Yb, Hf, Ti, Al, Cr, Mo, Nb, Ta, or a rare earth metal.

A module having a power semiconductor device and a ceramic capacitor which is configured for cooling the power semiconductor device.

A method to produce a ceramic matrix composite with controlled surface characteristics includes: applying a scrim ply to a surface of a fiber preform, where the fiber preform includes silicon carbide fibers coated with boron nitride; infiltrating the fiber preform and the scrim ply with a slurry, thereby forming an impregnated ply on an impregnated fiber preform; infiltrating the impregnated fiber preform and the impregnated ply with a melt comprising silicon, and then cooling, thereby forming a ceramic matrix composite having a ceramic surface layer thereon, where the ceramic surface layer has a predetermined thickness and is devoid of boron; machining or grit blasting the ceramic surface layer to form an intermediate layer suitable for coating; and depositing an environmental barrier coating on the intermediate layer. Thus, a ceramic matrix composite coated with the environmental barrier coating is formed with the intermediate layer in between.

A method for producing a member for a semiconductor manufacturing apparatus includes (a) a step of providing an electrostatic chuck, a supporting substrate, and a metal bonding material, the electrostatic chuck being made of a ceramic and having a form of a flat plate, the supporting substrate including a composite material having a difference in linear thermal expansion coefficient at 40 to 570° C. from the ceramic of 0.2×10.sup.−6/K or less in absolute value, and (b) a step of interposing the metal bonding material between a concave face of the supporting substrate and a face of the electrostatic chuck opposite to a wafer mounting face, and thermocompression bonding the supporting substrate and the electrostatic chuck at a predetermined temperature to deform the electrostatic chuck to the shape of the concave face.

A light absorbing member includes a ceramic composite having a plurality of first ceramic particles exhibiting positive resistance temperature characteristics in a first ceramics having an open porosity of 5% or lower.

A cordierite-based sintered body according to the present invention contains cordierite as a main component and silicon nitride or silicon carbide. The cordierite-based sintered body preferably has a thermal expansion coefficient less than 2.4 ppm/° C. at 40° C. to 400° C., an open porosity of 0.5% or less, and an average grain size of 1 μm or less.