An object of the present invention is to provide a ceramic bonded body comprising a ceramic substrate and a ceramic body such as a cylindrical body firmly bonded to each other and excellent in corrosion resistance in the ceramic substrate for the use for a semiconductor product producing/examining step. The ceramic bonded body according to the present invention comprises: a ceramic substrate in which a conductor is provided; and a ceramic body bonded to a bottom face of the ceramic substrate The ceramic bondedbody has a region, where no conductor is formed, in at least a part of a region above a bonding interface between the ceramic substrate and the ceramic body.

It is to provide a ceramic joint body and a ceramic structural body effectively used in semiconductor production and inspection devices including a hot plate or the like, and proposes a ceramic joint body by joining ceramic bodies to each other, in which coarse pores having an average diameter larger than an average particle size of ceramic particles constituting the ceramic body and a size of not more than 2000 µm are formed in a joining interface between the one ceramic body and the other ceramic body as well as a method of joining ceramics to each other.

An obj ect of the present invention is to provide a ceramic heater capable of stably supporting a semiconductor wafer and evenly heating the whole of a semiconductor wafer or the like without generating any warp in the semiconductor wafer or the like. The ceramic heater according to the present invention comprises: a disk-like ceramic substrate; a heating element formed on a surface of or inside the ceramic substrate; and through holes for letting lifter pins pass through the ceramic substrate, wherein the number of the formed through holes is three or more, and the through holes are formed in an area whose distance from the center of the ceramic substrate is 1/2 or more of the distance from the center to the outer edge of the ceramic substrate.

The present invention mainly relates to a method for reducing X-Y shrinkage during sintering low temperature ceramic comprising piling a constrain layer on a dielectric layer on a green ceramic body, which is printed with heterogeneous materials for conductors, resistors, capacitors and the like and/or disposed conductors, resistors, capacitors and the like to reduce shrinkage of the dielectric layer and the green ceramic body. The invention is characterized in that the constrain layer comprises windows in positions complying with the heterogeneous materials and/or conductors, resistors, capacitors and the like printed and/or disposed on the dielectric layer and the green ceramic body to make the heterogeneous materials and/or conductors, resistors, capacitors and the like not being covered when piling the constrain layer and the dielectric layers of the green ceramic body.

The object of the present invention is to provide an aluminum nitride sintered body which has excellent mechanical strength and in which ceramic particles is prevented from coming off from the surface and/or side thereof and generation of free particles is suppressed. The aluminum nitride sintered body of the present invention is wherein it contains sulfur.

A method of producing a material having a layer of ceramic as a first component, a layer of a metal as a second component and an intermediate layer lying between said layers and including said first and second components in continuously gradient ratios so that the properties of the material may change continuously; including a step to form said intermediate layer by igniting the mixture of powders of metallic and nonmetallic constitutive elements of said ceramic and powder of said metal and causing synthetic reaction of the powder mixture.