Abstract: A nickel-rhenium alloy powder comprising nickel as a main component, 0.1 to 10% by weight of rhenium, and having an average particle size of 0.05 to 1.0 ?m is provided. The nickel-rhenium alloy powder has a surface oxide film containing a nickel oxide and a rhenium oxide, and the amount of oxygen in the surface oxide film is 0.1 to 3.0% by weight relative to the total weight of the powder. The nickel-rhenium alloy powder is suitable, in particular, for forming internal electrode layers of a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. The surface oxide film allows bringing the sintering shrinkage behavior of electrode layers and ceramic layers closer to each other when the nickel-rhenium alloy powder is used, in particular, for forming internal electrodes of a multilayer ceramic electronic component.

Abstract: The invention provides a nickel-rhenium alloy powder that comprises nickel as a main component, 0.1 to 10% by weight of rhenium and 50 to 10,000 ppm of silicon in terms of silicon atoms, and that is suitable, in particular, for the formation of an internal electrode layer for a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. When used in particular for forming an internal electrode of a multilayer ceramic electronic component, the nickel-rhenium alloy powder of the invention delays sintering initiation and slows down sintering progress during firing, even for extremely fine powders, while bringing the sintering shrinkage behaviors of electrode layers and ceramic layers closer to each other. Moreover, there occurs no electrode spheroidizing caused by oversintering. A thinner, dense internal electrode having excellent continuity can be formed as a result.

Abstract: A nickel powder with a mean particle size of 0.05 to 1.0 ?m, the nickel powder having a thin oxidized layer of nickel on a surface thereof, an oxygen content of 0.3 to 3.0 wt. % and a carbon content of 100 ppm or less per specific surface area of 1 m2/g of the powder, in a weight proportion of carbon to the nickel powder of unit weight. When the powder is used for a conductive paste for forming inner electrode layers of a multilayer electronic component, it enables a decrease in the residual carbon amount after a binder removal process, thereby making it possible to obtain a multilayer ceramic electronic component excellent electrical characteristics and high reliability in which electrode layers excelling in continuity are formed without decreasing the strength and electrical characteristics of the electronic component or creating structural defects.

Abstract: A vacuum package has a chamber in which pressure is reduced to less than the atmospheric pressure, a functional component sealed in the chamber, and a material forming at least a part of the chamber. The material has at least one through hole to evacuate the chamber. In a cross section perpendicular to the material taken along the through hole, an edge portion of the material forming the through hole has an obtuse angle. The through hole is sealed with a sealing material.

Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.

Abstract: A nickel powder with an average particle size of 0.05 to 1.0 ?m, which is composed of nickel particles having an oxidized surface layer and containing sulfur, wherein the sulfur content with respect to the total weight of the powder is 100 to 2000 ppm, and the intensity of a peak identified to sulfur bonded to nickel in surface analysis by ESCA of the nickel particles varies in a direction toward the center from the surface of the particles, and this intensity has its maximum at a location deeper than 3 nm from the particle outermost surface. This nickel powder is manufactured by bringing a nickel powder containing sulfur and dispersed in a non-oxidizing gas atmosphere into contact with an oxidizing gas at a high temperature.

Abstract: A conductive paste for a terminal electrode of a multilayer ceramic electronic part, comprising (A) a spherical conductive powder which comprises chiefly copper, and which has a vitreous thin film on at least a portion of the surfaces thereof, (B) a flaky conductive powder comprising chiefly copper, (C) a glass powder, and (D) an organic vehicle, and may further contain (E) an aliphatic amine. When baked to form terminal electrodes for multilayer ceramic electronic parts, this paste exhibits extremely superior binder removal characteristics at low temperatures, and furthermore, it is superior in terms of oxidation resistance, binder removal characteristics and firing characteristics with no need for strict control of the firing conditions, thereby dense terminal electrodes that are superior in terms of adhesion and conductivity can be formed.

Abstract: A melt of nickel nitrate hydrate is introduced as droplets or liquid flow into a heated reaction vessel and thermally decomposed in a gas phase at a temperature of 1200° C. or more and at an oxygen partial pressure equal to or below the equilibrium oxygen pressure of nickel-nickel oxide at that temperature to manufacture a highly crystalline fine nickel powder with an extremely narrow particle size distribution. The oxygen partial pressure during the thermal decomposition is preferably 10?2 Pa or less, and a metal other than nickel, a semimetal and/or a compound of these may be added to the nickel nitrate hydrate melt to manufacture a highly crystalline nickel alloy powder or highly crystalline nickel composite powder. The resultant powder is suited in particular to thick film pastes such as conductor pastes for manufacturing ceramic multilayer electronic components.

Abstract: A nickel powder with a mean particle size of 0.05 to 1.0 ?m, the nickel powder comprising a thin oxidized layer of nickel on a surface thereof and having an oxygen content of 0.3 to 3.0 wt. % and a carbon content of 100 ppm or less per specific surface area of 1 m2/g of the powder, in a weight proportion of carbon to the nickel powder of unit weight. When the powder is used for a conductive paste for forming inner electrode layers of a multilayer electronic component, it enables the decrease in the residual carbon amount after a binder removal process, thereby making it possible to obtain a multilayer ceramic electronic component with excellent electric characteristics and high reliability in which electrode layers excelling in continuity are formed without decreasing the strength and electric characteristics of the electronic component or creating structural defects.

Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.

Abstract: Disclosed is a method of forming bump electrodes on wired circuit boards. A high-concentration impurity Si template doped with boron and having a pit formed therein is prepared. A plated resist is formed on the high-concentration impurity Si template and an opening is formed at the position of the pit. Then, an electric field is applied to the high-concentration impurity Si template and Au is buried in the opening in the plated resist to form a Au-plated buried layer. An electrode pad is formed on a semiconductor chip. With the plated resist separated from the high-concentration impurity Si template, the electrode pad of the semiconductor chip is aligned with the Au-plated buried layer and is bonded by thermo-compression bonding. The Au-plated buried layer is transferred to the electrode pad to form an Au bump on the semiconductor chip.

Abstract: A method for manufacturing a highly-crystallized double oxide powder composed of a single crystal phase which can be used as a phosphor material, a dielectric material, a magnetic material, etc. The method involves forming fine droplets of a raw material solution containing a raw material compound that includes at least one metal element and/or at least one semi-metal element that constitutes a double oxide, and heating these droplets at a high temperature, wherein the raw material solution is a solution which exhibits only one main peak attributable to the decomposition reaction of the raw material compound or a reaction intermediate thereof in a DTA profile when the solution is dried and solidified and subjected to TG-DTA measurement.

Abstract: A method for manufacturing a highly-crystallized oxide powder, wherein an oxide powder is produced by ejecting a starting material powder containing at least one metal element and/or semimetal element, which will become a constituent component of the oxide, into a reaction vessel together with a carrier gas through a nozzle; and heating the starting material powder at a temperature higher than the decomposition temperature or reaction temperature thereof and not lower than (Tm/2)° C., where Tm° C. stands for a melting point of the oxide, in a state in which the starting material powder is dispersed in a gas phase at a concentration of not higher than 10 g/L. In the above method, the starting material powder may be mixed and dispersed in the carrier gas by using a dispersing machine prior to being ejected into the reaction vessel through a nozzle.

Abstract: A method in which a metal powder is produced by ejecting a thermally decomposable metal compound powder into a reaction vessel through a nozzle together with a carrier gas under the condition V/S>600, where V is the flow rate of the carrier gas per unit time (liter/min), and S is the cross-sectional area of the nozzle opening part (cm2), and heating this metal powder at a temperature which is higher than the decomposition temperature of the metal compound powder and not lower than (Tm?200)° C., where Tm is the melting point of the metal, in a state where the metal compound powder is dispersed in the gas phase at a concentration of 10 g/liter or less. The method provides a fine, spherical, highly-crystallized metal powder which has a high purity, high density, high dispersibility and extremely uniform particle size, at low cost and using a simple process.

Abstract: A conductive paste for a terminal electrode of a multilayer ceramic electronic part, comprising (A) a spherical conductive powder which comprises chiefly copper, and which has a vitreous thin film on at least a portion of the surfaces thereof, (B) a flaky conductive powder comprising chiefly copper, (C) a glass powder, and (D) an organic vehicle, and may further contain (E) an aliphatic amine. When baked to form terminal electrodes for multilayer ceramic electronic parts, this paste exhibits extremely superior binder removal characteristics at low temperatures, and furthermore, it is superior in terms of oxidation resistance, binder removal characteristics and firing characteristics with no need for strict control of the firing conditions, thereby dense terminal electrodes that are superior in terms of adhesion and conductivity can be formed.

Abstract: A ferrite fine powder having a mean particle size of 0.1 to 30 &mgr;m and made of spherical single-crystal particles. The ferrite fine powder has superior physical properties and excellent magnetic properties desirable for use as a raw material for a dust core of coils, transformers, etc. The powder is prepared by forming a solution or suspension containing a compound or compounds of at least one of the metals forming the ferrite into fine droplets, and thermally decomposing the droplets at elevated temperatures.

Abstract: Disclosed is a wired board with a bump electrode whose production efficiency is improved. A high-concentration impurity Si template doped with boron and having a pit formed therein is prepared. A plated resist is formed on the high-concentration impurity Si template and an opening is formed in portion for the pit. Then, an electric field is applied to the high-concentration impurity Si template and Au is buried in the opening in the plated resist to form an Au-plated buried layer. An electrode pad is formed on a semiconductor chip. With the plated resist separated from the high-concentration impurity Si template, the electrode pad of the semiconductor chip is aligned with the Au-plated buried layer and is bonded by thermo-compression bonding. The Au-plated buried layer is transferred to the electrode pad to form Au bump on the semiconductor chip.

Abstract: A method in which a metal powder is produced by ejecting a thermally decomposable metal compound powder into a reaction vessel through a nozzle together with a carrier gas under the condition V/S>600, where V is the flow rate of the carrier gas per unit time (liter/min), and S is the cross-sectional area of the nozzle opening part (cm2), and heating this metal powder at a temperature which is higher than the decomposition temperature of the metal compound powder and not lower than (Tm−200)° C., where Tm is the melting point of the metal, in a state where the metal compound powder is dispersed in the gas phase at a concentration of 10 g/liter or less. The method provides a fine, spherical, highly-crystallized metal powder which has a high purity, high density, high dispersibility and extremely uniform particle size, at low cost and using a simple process.

Abstract: A method for manufacturing a highly-crystallized oxide powder, wherein an oxide powder is produced by ejecting a starting material powder comprising at least one metal element and/or semimetal element, which will become a constituent component of the oxide, into a reaction vessel together with a carrier gas through a nozzle; and heating the starting material powder at a temperature higher than the decomposition temperature or reaction temperature thereof and not lower than (Tm/2)° C., where Tm° C. stands for a melting point of the oxide, in a state in which the starting material powder is dispersed in a gas phase at a concentration of not higher than 10 g/L. In the above method, the starting material powder may be mixed and dispersed in the carrier gas by using a dispersing machine prior to being ejected into the reaction vessel through a nozzle.

Abstract: A method for manufacturing a highly-crystallized double oxide powder composed of a single crystal phase by forming fine droplets of a raw material solution containing a raw material compound that includes at least one metal element and/or at least one semi-metal element that constitutes a double oxide, and heating these droplets at a high temperature, wherein the raw material solution is a solution which exhibits only one main peak attributable to the decomposition reaction of the raw material compound or a reaction intermediate thereof in a DTA profile when the solution is dried and solidified and subjected to TG-DTA measurement. The method provides a highly-crystallized double oxide powder which is free from inclusion of impurities, has a high dispersibility and a uniform particle size, and composed of a single crystal phase, by a simple procedure at low cost.