Abstract: A ceramic member, in a carrier device, including: a plurality of ceramic layers; a clamping electrode formed on a first ceramic layer among the plurality of ceramic layers and inside of the plurality of ceramic layers, and configured to attract a dielectric material by electrostatic force; an electric heating element formed on a second ceramic layer, which is more distant from a side holding a carried object than the first ceramic layer among the plurality of ceramic layers, and configured to generate heat using electric power; a power feed port; a land formed on a third ceramic layer among the plurality of ceramic layers, and configured to receive electric power through the power feed port; and a via arranged to pass through at least one of the plurality of ceramic layers and provided as a conductive material to electrically connect the electric heating element with the land.

Abstract: A method of making a semiconductor manufacturing equipment component, such as an electrostatic chuck, includes an application step of applying a photosensitive metal paste onto a ceramic green sheet, which is to become the body substrate, the photosensitive metal paste being a heating element material; an exposure-and-development step of exposing the photosensitive metal paste, which has been applied onto the ceramic green sheet, to light and developing the photosensitive metal paste to form an intermediate heating element, which is to become the heating element, on the ceramic green sheet; and a firing step of co-firing the ceramic green sheet and the intermediate heating element to form the body substrate and the heating element.

Abstract: A ceramic member, in a carrier device, includes: a plurality of ceramic layers that have insulating properties and are integrally sintered; a clamping electrode formed on a first ceramic layer among the plurality of ceramic layers and inside of the plurality of ceramic layers, and configured to attract a dielectric material by electrostatic force; a power feed port configured to receive a supply of electric power to the clamping electrode from outside of the ceramic member; a land formed on a second ceramic layer, which is different from the first ceramic layer among the plurality of ceramic layers, and configured to receive electric power through the power feed port; and a via arranged to pass through at least one of the plurality of ceramic layers and provided as a conductive material to electrically connect the clamping electrode with the land.

Abstract: A ceramic member, in a carrier device, includes: a plurality of ceramic layers that have insulating properties and are integrally sintered; a clamping electrode formed on a first ceramic layer among the plurality of ceramic layers and inside of the plurality of ceramic layers, and configured to attract a dielectric material by electrostatic force; a power feed port configured to receive a supply of electric power to the clamping electrode from outside of the ceramic member; a land formed on a second ceramic layer, which is different from the first ceramic layer among the plurality of ceramic layers, and configured to receive electric power through the power feed port; and a via arranged to pass through at least one of the plurality of ceramic layers and provided as a conductive material to electrically connect the clamping electrode with the land.

Abstract: A ceramic member, in a carrier device, including: a plurality of ceramic layers; a clamping electrode formed on a first ceramic layer among the plurality of ceramic layers and inside of the plurality of ceramic layers, and configured to attract a dielectric material by electrostatic force; an electric heating element formed on a second ceramic layer, which is more distant from a side holding a carried object than the first ceramic layer among the plurality of ceramic layers, and configured to generate heat using electric power; a power feed port; a land formed on a third ceramic layer among the plurality of ceramic layers, and configured to receive electric power through the power feed port; and a via arranged to pass through at least one of the plurality of ceramic layers and provided as a conductive material to electrically connect the electric heating element with the land.

Abstract: A method for manufacturing ceramic balls useful as ball bearings is described, wherein spherical green bodies are formed into ceramic balls having few pores and substantially uniform strength distribution, using a rubber die having a hardness not higher than 65.

Abstract: A zirconia containing ceramic ball is formed of a zirconia containing ceramic material which contains in an amount of not less than 10% by volume the zirconia ceramic phase composed predominantly of zirconium oxide. The size of the largest pore among pores present in a region extending radially from the surface of the ball to a depth of 50 &mgr;m as observed on a polished cross section of the ball taken substantially across the center of the ball is not greater than 3 &mgr;m. The ceramic ball can be manufactured through firing a green body whose relative density is enhanced to not lower than 61% by use of rolling granulation.

Abstract: A zirconia sintered body comprising a zirconia and a titanium oxide and a process for producing a zirconia sintered body which comprises sintering a raw material mixture comprising a zirconia and a titanium oxide in an oxygen-free atmosphere comprising one of hydrogen, nitrogen and water.

Abstract: A ceramic bearing ball in which at least a portion of a constituent ceramic is formed of an electrically conductive inorganic compound phase, whereby a proper electrical conductivity is imparted to the ceramic. Thus, electrifying of a bearing ball is prevented or effectively suppressed. This prevents the problem involved in production of balls of small diameter wherein such balls adhere to an apparatus (e.g., a container) during production thereof, thus hindering smooth progress of the production process. In addition, when ceramic balls are used in precision electronic equipment, such as a hard disk drive of a computer, which is operated at high rotational speed, adhesion of foreign substance due to electrification of the balls, and resultant generation of abnormal noise or vibration can be prevented or effectively suppressed.

Abstract: A conductive ceramic bearing ball made of composite ceramic and having a mixed microstructure of a silicon nitride phase and a titanium nitride phase. The content ratio of the silicon nitride phase to the titanium nitride phase is such that the conductive ceramic bearing ball has an average coefficient of linear expansion within a temperature range of 20° C.-100° C. of from 2×10−6/K to 5×10−6/K.

Abstract: A high-purity alumina sintered body having an alumina purity of not less than 99.9% by mass and a relative density of not less than 97% and exhibiting a weight loss of not greater than 100×10−4 kg/m2 when immersed in boiling 6N H2SO4 or 6N NaOH aqueous solution for 24 hours as measured according to JIS R1614 (1993). The high-purity alumina sintered body is obtained by firing a green body formed from an alumina powder having an alumina purity of not less than 99.9% by mass and containing, as impurities, Si, an Mg, Fe and alkali metals including Na, K and Li in a total amount of less than 100 ppm.

Abstract: A sintered silicon nitride member formed predominantly of silicon nitride, wherein at least a surface of the sintered member has a lightness VS of 3.0 to 9.0 and/or a chroma CS of not greater than 3.0. The sintered member facilitates identification of defects such as pore and/or foreign matter of different color formed at the surface and is capable of enhancing inspection accuracy. Also disclosed is a sintered silicon nitride member in the form of a ceramic ball having such a lightness on its surface.

Abstract: A method of making spherical bodies from powder, which comprises (1) preparing an adjusted powder so as to have at least one powder characteristic selected from the group consisting of an average particle size, a powder particle size distribution and a BET specific surface area, (2) preparing nuclei having a particle size larger than that of the adjusted powder, (3) rotating the nuclei, and (4) adding the adjusted powder and a solvent to the rotating nuclei so that particles of the adjusted powder accumulate on the nuclei to form granular bodies. Also disclosed is a spherical body having a core or nucleus formed in the spherical body, an adjusted powder composition for forming a spherical body, and a method for manufacturing spherical sintered bodies of silicon nitride.

Abstract: A conductive ceramic bearing ball made of composite ceramic and having a mixed microstructure of a silicon nitride phase and a titanium nitride phase. The content ratio of the silicon nitride phase to the titanium nitride phase is such that the conductive ceramic bearing ball has an average coefficient of linear expansion within a temperature range of 20° C.-100° C. of from 2×10−6/K to 5×10−6/K.

Abstract: A method for manufacturing ceramic balls useful as ball bearings is described, wherein spherical green bodies are formed into ceramic balls having few pores and substantially uniform strength distribution, using a rubber die having a hardness not higher than 65.

Abstract: A ceramic ball is described wherein no magnetic inclusion is observed on a surface of said ceramic ball, or when a magnetic inclusion is observed on the surface, dmax of the observed magnetic inclusion is not greater than 20 &mgr;m, wherein dmax is the distance between parallel lines circumscribing the observed magnetic inclusion and whose distance is the greatest among such circumscribing parallel lines.

Abstract: A silicon nitride sintered body, e.g., a ball, exhibiting excellent machinability is disclosed, having an X-ray diffraction profile measured on a cross section of the silicon nitride sintered body by means of a diffractometer such that X&bgr;/(X&agr;+X&bgr;) is 0.9−1, wherein X&agr; is the highest peak intensity associated with a silicon nitride phase and X&bgr; is the highest peak intensity associated with &bgr; silicon nitride phase, and silicon nitride grains of said body have an average grain size dav of 0.5-5.0 &mgr;m and a grain aspect ratio &agr; of 1-5, and are present in an average number of not less than 2×104 per square millimeter in a predominant crystalline phase observed on the cross section.

Abstract: A ceramic bearing ball in which at least a portion of a constituent ceramic is formed of an electrically conductive inorganic compound phase, whereby a proper electrical conductivity is imparted to the ceramic. Thus, electrifying of a bearing ball is prevented or effectively suppressed. This prevents the problem involved in production of balls of small diameter wherein such balls adhere to an apparatus (e.g., a container) during production thereof, thus hindering smooth progress of the production process. In addition, when ceramic balls are used in precision electronic equipment, such as a hard disk drive of a computer, which is operated at high rotational speed, adhesion of foreign substance due to electrification of the balls, and resultant generation of abnormal noise or vibration can be prevented or effectively suppressed.

Abstract: A high-purity alumina sintered body having an alumina purity of not less than 99.9% by mass and a relative density of not less than 97% and exhibiting a weight loss of not greater than 100×10-−4 kg/m2 when immersed in boiling 6N H2SO4 or 6N NaOH aqueous solution for 24 hours as measured according to JIS R1614 (1993). The high-purity alumina sintered body is obtained by firing a green body formed from an alumina powder having an alumina purity of not less than 99.9% by mass and containing, as impurities, Si, an Mg, Fe and alkali metals including Na, K and Li in a total amount of less than 100 ppm.

Abstract: A ceramic bearing ball capable of preventing irregular vibrations of, for example, a hard disk drive and having a high accuracy. The ceramic ball is characterized as having a sphericity of not more than 0.08 &mgr;m, a surface roughness of not more than 0.012 &mgr;m and a maximum surface pore size of 5 &mgr;m.