A zirconia sintered body is provided in which the strength between layers of powders is improved. A flexural strength of a test sample of the zirconia sintered body, measured pursuant to JISR1601, is not less than 1100 MPa. The test sample is formed by preparing a plurality of zirconia powders, each containing zirconia and a stabilizer that suppresses phase transition of zirconia, the zirconia powders differing in a composition, layering the zirconia powders to form a zirconia composition, and sintering the zirconia composition to form a zirconia sintered body. The flexural strength is measured such that a load point is positioned at a boundary of the zirconia powders, the boundary traversing the test sample of the sintered body along a direction of load application.

Provided is at least any of a layered body, which has a change in texture derived from zirconia, particularly a change in translucency and is suitable as a dental prosthetic member, a precursor thereof, or a method for producing these. There is provided a layered body having a structure in which two or more layers containing zirconia containing a stabilizer are layered, the layered body including at least: a first layer containing zirconia having a stabilizer content of higher than or equal to 4 mol %; and a second layer containing zirconia having a stabilizer content different from that of the zirconia contained in the first layer.

A semiconductor manufacturing device member according to the present invention includes a ceramic disc with an internal electrode and a ceramic shaft that supports the disc. The disc and the shaft are integrated without having a bonding interface.

A proton-conductive solid electrolyte member has an electrolyte layer and an anode layer. The electrolyte layer contains a metal oxide having a perovskite crystal structure. The anode layer contains Fe.sub.2O.sub.3 and the metal oxide. The metal oxide is a metal oxide expressed by the following formula [1], or a mixture or a solid solution of a metal oxide expressed by the following formula [1]: A.sub.aB.sub.bM.sub.cO.sub.3-, where A denotes one element selected from the group consisting of Ba and Ca; B denotes one element selected from the group consisting of Ce and Zr; M denotes one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc; a is a number satisfying 0.85a1; b is a number satisfying 0.50b1; c is a number satisfying c=1b; and is an oxygen deficiency amount.

A method for manufacturing an electrostatic chuck with multiple chucking electrodes made of ceramic pieces using metallic aluminum as the joining. The aluminum may be placed between two pieces and the assembly may be heated in the range of 770C to 1200C. The joining atmosphere may be non-oxygenated. After joining the exclusions in the electrode pattern may be machined by also machining through one of the plate layers. The machined exclusion slots may then be filled with epoxy or other material. An electrostatic chuck or other structure manufactured according to such methods.

A method for producing a component includes a) providing at least two preforms each made of a carbon composite material, b) joining the at least two preforms at least at one respective connecting surface to form a composite, in which a joining compound is introduced between the joining surfaces of the preforms and then cured and the joining compound contains silicon carbide and at least one polymer adhesive, and c) siliconizing the composite to form the component. A component, such as an optical component produced thereby, is also provided.

A method for producing a dielectric ceramic includes: shaping mixed powdery particles including a cordierite material (2MgO.2Al.sub.2O.sub.3.5SiO.sub.2) and a low-temperature-sintering material including Al, Si and Sr, the Si being partially vitrified; and firing the resultant shaped body. The method includes the step of wet-pulverizing the low-temperature-sintering material together with at least the cordierite material to prepare mixed powder particles having a median diameter D50 less than 1 m; and, in a process until a time of the preparation of the mixed powder particles, the low-temperature-sintering material undergoes no step of wet-pulverizing only the low-temperature-sintering material, and drying the resultant pulverized material.

A method for the joining of ceramic pieces with a hermetically sealed joint comprising brazing a layer of joining material between the two pieces. The wetting and flow of the joining material is controlled by the selection of the joining material, the joining temperature, the joining atmosphere, and other factors. The ceramic pieces may be aluminum nitride and the pieces may be brazed with an aluminum alloy under controlled atmosphere. The joint material is adapted to later withstand both the environments within a process chamber during substrate processing, and the oxygenated atmosphere which may be seen within the shaft of a heater or electrostatic chuck.

A method for the joining of ceramic pieces with a hermetically sealed joint comprising brazing a layer of joining material between the two pieces. The wetting and flow of the joining material is controlled by the selection of the joining material, the joining temperature, the joining atmosphere, and other factors. The ceramic pieces may be on a non-diffusable type, such as aluminum nitride, alumina, beryllium oxide, and zirconia, and the pieces may be brazed with an aluminum alloy under controlled atmosphere. The joint material is adapted to later withstand both the environments within a process chamber during substrate processing, and the oxygenated atmosphere which may be seen within the shaft of a heater or electrostatic chuck.

A power-module substrate and a heat sink made of an aluminum-impregnated silicon carbide formed by impregnating aluminum in a porous body made of silicon carbide; where yield strength of a circuit layer is 1 (MPa), a thickness of the circuit layer is t1 (mm), a bonding area of the circuit layer and a ceramic board is A1 (mm.sup.2), yield strength of a metal layer is 2 (MPa), a thickness of the metal layer is t2 (mm), a bonding area of the metal layer and the ceramic board is A2 (mm.sup.2); the thickness t1 is formed to be between 0.1 mm and 3.0 mm (inclusive); the thickness t2 is formed to be between 0.15 mm and 5.0 mm (inclusive); the thickness t2 is formed larger than the thickness t1; and a ratio {(2t2A2)/(1t1A1)} is in a range between 1.5 and 15 (inclusive).