Abstract: In order to provide a multi-layer electronic component in which the occurrence of delamination between the ceramic layer and the internal electrode is restricted and a method for manufacturing the same, the multi-layer electronic component of the present invention comprises a stack formed by stacking piezoelectric layers and internal electrodes one on another alternately and a pair of external electrodes formed on two opposing side faces of the stack, wherein the internal electrode consists of a first internal electrode connected to the external electrode formed on one of the two side faces and a second internal electrode located between the first internal electrode and connected to the external electrode formed on the other one of the two side faces, and wherein the internal electrodes and the piezoelectric layers are faced in proximity so that a space between them is 2 ?m or less over an area occupying 50% or more of the active region where the first internal electrode and the second internal electrode oppo

Abstract: Disclosed is an electrostatic chuck comprising a ceramic dielectric layer having a surface for placing thereon a work that is to be held, and an electrode provided on a surface opposite to the surface of the ceramic dielectric layer for placing the work thereon, wherein: the placing surface of the ceramic dielectric layer is sectionalized into an outer peripheral region and a central region by gas injection grooves extending in a circumferential manner; the surface roughness Ra(o) of the outer peripheral region of the placing surface and the surface roughness Ra(i) ot the central region satisfy the following conditions: 0.6≦Ra(i)≦1.5 &mgr;m Ra(o)≦0.7 &mgr;m Ra(i)≧Ra(o)  and the outer peripheral region of the placing surface is higher than the inner peripheral region by not less than 0.6 &mgr;m.

Abstract: Disclosed is an electrostatic chuck comprising a ceramic dielectric layer having a surface for placing thereon a work that is to be held, and an eloctrode provided on a surface opposite to the surface of the ceramic dielectric layer for placing the work thereon, wherein:

Abstract: A sintered product of silicon nitride has a crystal phase of RE2Si3N2O5 or RE3AlSi2O7N2 (RE is an element of the Group 3a of periodic table) precipitated on the grain boundaries of the silicon nitride crystal phase, and exhibits a high strength over a wide temperature region of from normal temperature to a temperature of as high as 1000° C., as well as excellent oxidation resistance and static fatigue property. The sintered product of silicon nitride is very useful as parts for heat engines, such as parts for engines and parts for gas turbines.

Abstract: A silicon nitride sintered body containing a .beta.-silicon nitride crystal phase and further containing at least a rare earth element component and an aluminium component in a grain boundary phase, wherein the intensity ratio (X2/X1) of the Si peak X.sub.2 at 521 cm.sup.-1 to the Si.sub.3 N.sub.4 peak X.sub.1 at 206 cm.sup.-1, as detected by a Raman spectrochemical analysis method, is 0.2 to 3. A very minor amount of Si (elemental silicon), as detected by the Raman spectrochemical analysis method, is precipitated in the sintered body, and by this precipitation of Si, strength and toughness are markedly increased.

Abstract: The whiskers-reinforced ceramics of the present invention is prepared from alumina powder activated by dry milling, with which Ti-based whiskers are mixed, by molding and sintering said mixture.By the present invention the bending strength of the sintered body can be increased without impairing the effect of improving the fracture toughness which is imparted by the incorporation of Ti-based whiskers, since the particle size of alumina crystal in the sintered body can be controlled to 3 microns or less.