Ngk Insulators, Inc.

Ngk Insulatores, Ltd.

Toru Hayase

Kenji Morimoto

Yoshimasa Kobayashi

Yuji Katsuda

Naohito Yamada

Satoshi Yamazaki

Shinji Kawasaki

Naomi Teratani

Kosuke Ujihara

Yukihisa Takeuchi

Morimichi Watanabe

Masahiro Kida

Takahiro Tomita

Jun Yoshikawa

Masaki Ishikawa

Asumi Jindo

Shinji Suzuki

Shinpei Oshima

Satoshi Yamakazi

A honeycomb structure has a plurality of cells formed by a plurality of partition walls. The partition walls are formed of a porous material composed predominantly of cordierite. Each partition wall includes surface layer portions having a porosity of 50% or more and an inside portion having a porosity of 50% or more, the surface layer portions being portions ranging respectively from opposite surfaces to a depth corresponding to 25% of the thickness of the partition wall, and the inside portion being the other portion. The surface layer portions and the inside portion both include pores having axial pore widths of less than 30 &#x3bc;m and pores having axial pore widths of 30 &#x3bc;m or more. A mean axial pore width in the surface layer portions is smaller than a mean axial pore width in the inside portion.

Honeycomb structure and method of producing honeycomb structure

A heater part of a planar sensor element includes: a Pt heater element; and an insulating layer including 90-99.9 wt % of an insulating material having a different coefficient of thermal expansion from a solid electrolyte forming a base part of the element. The heater part other than a heater electrode is buried in the base part. The heater element has a thickness of 10-50 &#x3bc;m and is covered with the insulating layer. The insulating layer has a porosity of 4% or less and a thickness of 50-150 &#x3bc;m. The distances of the insulating layer from an end portion of the element, from a main surface on which the heater electrode is located, and from a side surface of the element are respectively 0.25-0.75 mm, 0.20-0.60 mm, and 0.20-0.60 mm. The total length of the element is 80.0 mm or less.

Sensor element

A heater part of a planar sensor element includes: a heater element containing Pt; an insulating layer covering the heater element; and a heater electrode located on a main surface of the sensor element to be exposed. A portion of the heater part other than the heater electrode is buried in a base part formed of a solid electrolyte. The insulating layer at least contains MgO, MgAlO, and MgNbOin a weight percentage of 97 wt % to 100 wt % in total. MgO, MgAlO, and MgNbOare contained in weight percentages of 30 wt % to 60 wt %, 30 wt % to 60 wt %, and 0.5 wt % to 15 wt %, respectively. The insulating layer has a porosity of 4% or less.

A heater part of a planar sensor element includes: a Pt heater element; and an insulating layer including 90-99.9 wt % of an insulating material having a different coefficient of thermal expansion from a solid electrolyte forming a base part of the element. The heater part other than a heater electrode is buried in the base part. The insulating layer includes: a porous portion having a porosity of 20-40%; and a dense portion having a porosity of 4% or less. The heater element is covered with the dense portion. A laminated portion in which the porous portion and the dense portion are laminated has a total thickness of 25-100 &#x3bc;m. The dense portion has a thickness of 5 &#x3bc;m or more. A thickness ratio of the dense portion to the porous portion is 0.05 to 2.0.

The honeycomb structure includes a honeycomb structure body made of a zeolite material containing at least a coarse particle zeolite having a large average particle diameter (coarse zeolite particles). A fine particle zeolite having an average particle diameter smaller than that of the coarse particle zeolite (fine zeolite particles), and an inorganic bonding material, the coarse particle zeolite (the coarse zeolite particles) is a chabazite type zeolite in which an average particle diameter of primary particles is 2 &#x3bc;m or more and 6 &#x3bc;m or less, and in the fine particle zeolite (the fine zeolite particles), an average particle diameter of primary particles is 0.02 &#x3bc;m or more and smaller than 2 &#x3bc;m, and in the zeolite material which is comprised the honeycomb structure body, a ratio of a volume of pores having pore diameters of 0.02 to 0.15 &#x3bc;m to a volume of all pores is 42% or less.

Honeycomb structure

The manufacturing method includes a step of mixing a coarse particle zeolite, a fine particle zeolite, and a raw material of an inorganic bonding material to prepare a zeolite raw material; a step of forming the prepared zeolite raw material into a honeycomb shape to prepare a honeycomb formed body; and a step of firing the prepared honeycomb formed body to prepare the honeycomb structure. In the step of preparing the zeolite raw material, as the coarse particle zeolite, a chabazite type zeolite having a specific average particle diameter, the fine particle zeolite having a specific average particle diameter, the raw material of the inorganic bonding material which includes at least basic aluminum lactate is used.

Manufacturing method of honeycomb structure

A voltage-nonlinear resistor elementincludes a voltage-nonlinear resistor (referred simply as 'resistor')and a pair of electrodesandbetween which the resistoris interposed. The resistorhas a multilayer structure including a first layercomposed primarily of zinc oxide, a second layercomposed primarily of zinc oxide, and a third layercomposed primarily of a metal oxide other than zinc oxide. The second layeris adjacent to the first layerand has a smaller thickness and a higher volume resistivity than the first layerThe third layeris adjacent to the second layer

Voltage-nonlinear resistor element and method for producing the same

A voltage nonlinear resistive element includes a resistor containing a joined body in which a zinc oxide ceramic layer composed mainly of zinc oxide and having a volume resistivity of 1.0&#xd7;10&#x3a9;cm or less is joined to a bismuth oxide layer composed mainly of bismuth oxide, and a pair of electrodes disposed on the resistor such that an electrically conductive path passes through a joint surface between the zinc oxide ceramic layer and the bismuth oxide layer. In this element, the zinc oxide ceramic layer of the joined body has a lower volume resistivity than before. This can result in a lower clamping voltage in a high-current region than before.

Voltage nonlinear resistive element and method for manufacturing the same

The voltage nonlinear resistive element includes a resistor containing a joined body in which a zinc oxide ceramic layer composed mainly of zinc oxide and having a volume resistivity of less than 1.0&#xd7;10&#x3a9;cm is joined to a rare-earth metal oxide layer composed mainly of a rare-earth metal oxide, and a pair of electrodes disposed on the resistor such that an electrically conductive path passes through a junction between the zinc oxide ceramic layer and the rare-earth metal oxide layer. In this element, the zinc oxide ceramic layer of the joined body has a lower volume resistivity than before. This can result in a lower clamping voltage in a high electric current region than before.

The present invention provides a voltage nonlinear resistor containing zinc oxide as a major component, wherein the degree of orientation f(100) of the (100) plane of zinc oxide is 0.40 or more and is represented by the following equation: f(100)=I(100)/(I(100)+I(002)+I(101)), where I(hkl) represents the peak intensity (integral) of a (hkl) plane.

Voltage nonlinear resistor

An electrostatic chuck is provided with a ceramic substratein which an electrodeis embedded, an electrode terminalexposed at the bottom of a concave portiondisposed on the back surface of the ceramic substrate, a power feed memberto supply an electric power to the electrode, and a joining layerto connect this power feed memberto the ceramic substrate. The joining layeris formed by using a AuGe based alloy, a AuSn based alloy, or a AuSi based alloy. The ceramic substrateand the power feed memberare selected in such a way that the thermal expansion coefficient difference D calculated by subtracting the thermal expansion coefficient of the ceramic substratefrom the thermal expansion coefficient of the power feed membersatisfies &#x2212;2.2&#x2266;D&#x2266;6 (unit: ppm/K).

Member for semiconductor manufacturing apparatus

A mixed powder was prepared by weighing YbOand SrCOin such a way that the molar ratio became 1:1. The resulting mixed powder was subjected to uniaxial pressure forming, so as to produce a disc-shaped compact. The compact was heat-treated in an air atmosphere, so that a complex oxide was synthesized. The resulting complex oxide was pulverized. After the pulverization, a slurry was taken out and was dried in a nitrogen gas stream, so as to produce a synthesized powder material. The resulting synthesized powder material was subjected to uniaxial pressure forming, so as to produce a disc-shaped compact. The resulting compact was fired by a hot-press method, so as to obtain a corrosion-resistant member for semiconductor manufacturing apparatus. The resulting corrosion-resistant member was made from a SrYbO.

Corrosion-resistant member for semiconductor manufacturing apparatus and method for manufacturing the same

Initially, an YbOraw material was subjected to uniaxial pressure forming at a pressure of 200 kgf/cm, so that a disc-shaped compact having a diameter of about 35 mm and a thickness of about 10 mm was produced, and was stored into a graphite mold for firing. Subsequently, firing was performed by using a hot-press method at a predetermined firing temperature (1,500&#xb0; C.), so as to obtain a corrosion-resistant member for semiconductor manufacturing apparatus. The press pressure during firing was specified to be 200 kgf/cmand an Ar atmosphere was kept until the firing was finished. The retention time at the firing temperature (maximum temperature) was specified to be 4 hours. In this manner, the corrosion-resistant member for semiconductor manufacturing apparatus made from an YbOsintered body having an open porosity of 0.2% was obtained.

A method for manufacturing an alumina sintered body of the present invention comprises: (a) forming a mixed powder containing at least AlOand MgFor a mixed powder containing AlO, MgF, and MgO into a compact having a predetermined shape; and (b) performing hot-press sintering of the compact in a vacuum atmosphere or a non-oxidizing atmosphere to form an alumina sintered body, in which when a amount of MgFto 100 parts by weight of AlOis represented by X (parts by weight), and a hot-press sintering temperature is represented by Y (&#xb0; C.), the hot-press sintering temperature is set to satisfy the following equations (1) to (4)1,120&#x2266;&#x2266;1,300&#x2003;&#x2003;(1)0.15&#x2266;&#x2266;1.89&#x2003;&#x2003;(2)&#x2266;&#x2212;78.7+1,349&#x2003;&#x2003;(3)&#x2267;&#x2212;200+1,212&#x2003;&#x2003;(4).

Alumina sintered body, method for manufacturing the same, and semiconductor manufacturing apparatus member

A method for producing an aluminum nitride sintered product according to the present invention includes the steps of (a) preparing a powder mixture that contains AlN, 2 to 10 parts by weight of EuOwith respect to 100 parts by weight of AlN, AlOsuch that a molar ratio of AlOto EuOis 2 to 10, and TiOsuch that a molar ratio of TiOto AlOis 0.05 to 1.2, but not Sm; (b) producing a compact from the powder mixture; and (c) firing the compact by subjecting the compact to hot-press firing in a vacuum or in an inert atmosphere.

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Nagoya, Japan

Toru Hayase