Ngk Insulators, Inc.

Masao Nishioka

Keiichiro Watanabe

Mitsuji Ikeda

Naotaka Kato

Kiyoshi Araki

Masayuki Nozaki

Naotaka Katoh

Shinji Kawasaki

Shoji Seike

Hirotake Yamada

Yasufumi Aihara

Hiroya Sugimoto

Toshiichi Ikami

Mitsuru Ohta

An electrostatic chuck includes an electrostatic electrode embedded in a ceramic base having a wafer-supporting surface capable of holding a wafer, the electrostatic electrode being parallel to the wafer-supporting surface. The ceramic base is composed of a dense ceramic having a MgO content of 99% by weight or more. The electrostatic electrode is a disc-like electrode composed of, for example, at least one metal selected from the group consisting of Ni, Co, and Fe. The electrostatic electrode includes a conductive tablet connected to the center thereof. The tablet is exposed at the bottom of a counter-bored hole formed so as to reach the tablet from a back surface of the ceramic base, and is connected to a feeding terminal, composed of Ni, inserted into the counter-bored hole.

Electrostatic chuck and method for producing the same

A heating device includes an electrode embedded near the heating surface of the ceramic base substantially in parallel to the heating surface. In the rear surface of the ceramic base, a terminal hole extending toward the electrode is formed. Between the bottom surface of the terminal hole and electrode, a conductive ceramic member is embedded and connected to the electrode. The conductive ceramic member has a thermal expansion coefficient equal to that of the ceramic base. The electrode and terminal are electrically connected through the conductive ceramic member.

Heating device

A heating device includes a high-frequency electrode embedded substantially in parallel with a heating surface of a ceramics base in the vicinity of the heating surface. A conducting hole toward this high-frequency electrode is formed in a back face of the ceramics base. This high-frequency electrode has a trapezoidal cone-like concave section toward the conducting hole at a region opposed to the conducting hole.

A heating device is provided, including an insulating ceramic base having a heating surface for heating an object. A high frequency electrode is embedded in the insulating ceramic base in the vicinity of the heating surface, and a heating body is embedded in the base in a location that is further from the heating surface than the location of the high frequency electrode. A low resistance ceramic member is provided so as to be exposed to a part of the heating surface of the insulating ceramic base and to be connected to a conductive member inside of the insulating ceramic base. A main component of the material of the low resistance ceramic member is common to that of the insulating ceramic base, and the respective thermal expansion coefficients are equivalent.

This invention relates to a corrosion-resistant member comprising a ceramic substrate and a silicon carbide film formed through a chemical vapor deposition process and having a resistivity at room temperature of 20-500 &OHgr;&middot;cm, and a method of manufacturing the same as well as an heating apparatus using the same.

Corrosion-resistant member, method of manufacturing the same and apparatus for heating corrosive substance

A corrosion-resistant member includes a substrate made of a ceramic material and having a diameter of at least 200 mm, and a film of chemically vapor deposited silicon carbide having a thickness of not less than 0.5 mm and covering at least such a portion of the surface of the substrate that is to contact a corrosive material. A process is disclosed for producing such a corrosion-resistant member, which process includes thermally treating the film at a temperature higher, by not less than 50&deg; C. centigrade, than a film-forming temperature at which the film of silicon carbide is formed, after the formation of the silicon carbide film.

Process for producing a corrosion-resistant member

A structural body has an aluminum nitride sintered body, a silicon carbide film formed on a surface of the sintered body, and an intermediate layer generated between the sintered body and the silicon carbide film. The intermediate layer is mainly made of a silicon nitride. Preferably, the intermediate layer includes smaller than 5 wt % of carbon and smaller than 5 wt % of aluminum, and a thickness of the intermediate layer is greater than 0.2 &mgr;m.

Structural body and method of producing the same

A ceramic article having a base made of an insulating ceramic material, the insulating ceramic material includes a metal element, and a conductive surface layer provided on the base, wherein the conductive surface layer includes carbon atoms as its main component, and wherein the conductive surface layer further includes silicon atoms and atoms of the metal element present in the insulating ceramic material.

Ceramic articles and method for manufacturing the same

A corrosion-resistant member against a chlorine-based gas, which member is to be exposed to a chlorine-based gas atmosphere at temperatures of not less than 600&deg; C. and includes a sintered body made of aluminum nitride and a film of silicon carbide covering a surface of the sintered body and formed by chemical vapor deposition.

Corrosion-resistant members against a chlorine-based gas

A light-impermeable, high purity silicon carbide material including polycrystals of silicon carbide as a main ingredient, wherein the silicon carbide material has a porosity of not more than 0.1%, the content of each of metal elements contained in the silicon carbide material is not more than 200 ppb, a weight ratio of silicon relative to the entire weight of the silicon carbide material is 69.00 to 69.90 wt %, and a light transmittance of the silicon carbide material in a wavelength range of 0.4 to 25 .mu.m is not more than 0.05% per a thickness of 0.5 mm.

Light-impermeable, high purity silicon carbide material, a light

A corrosion-resistant member includes a substrate made of a ceramic material and having a diameter of at least 200 mm, and a film of chemically vapor deposited silicon carbide having a thickness of not less than 0.5 mm and covering at least such a portion of the surface of the substrate that is to contact a corrosive material. A process is disclosed for producing such a corrosion-resistant member, which process includes thermally treating the film at a temperature higher, by not less than 50.degree. C. centigrade, than a film-forming temperature at which the film of silicon carbide is formed, after the formation of the silicon carbide film.

Corrosion-resistant member and a producing process thereof

A gas-tight article includes a sintered body composed mainly of a silicon carbide, and a film of silicon carbide formed on a surface of the sintered body by chemical vapor deposition and covering said surface of the sintered body, wherein cracks are formed in the film of the silicon carbide, and the cracks are filled with metallic silicon.

Gas-tight article and a producing process thereof

For the production of sintered lanthanum manganite bodies, such as tubes for solid oxide fuel cell air electrodes, there is used extrudable lanthanum manganite paste having a pH of not less than 8, of a dried unfired extruded lanthanum manganite body formed of material having a pH, measured by grinding the material and diluting with water, of at least 7.3. Providing alkalinity in such a paste or body reduces crack formation and increases productivity.

Extrudable lanthanum manganite paste, extruded lanthanum manganite body

A porous sintered lanthanum manganite body has an alkali metal content of at least 100 ppm and the alkali metal concentration in the lanthanum manganite crystal grains is higher adjacent the grain boundaries than away from the grain boundaries. The body is made by forming a shaped green body of material and firing the shaped green body, the sinterable material has a content of alkali metal of at least 100 ppm. The sintered body has improved strength, and is suitable for example as an air electrode of a solid oxide fuel cell.

Porous sintered lanthanum manganite bodies and method of manufacturing

A process is disclosed for producing a solid oxide fuel cell including a solid electrolyte plate, and an air electrode and a fuel electrode provided on opposite surfaces of said solid electrolyte plate. The process comprising the step of joining a film of oxygen ion-conductive zirconia as the solid electrolyte plate to lanthanum manganate as the air electrode through a layer containing a compound selected from a manganese compound and a cobalt compound by press contacting them under heating.

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Tokoname, Japan

Masao Nishioka