Abstract: Provided are a purification method and purification apparatus for an alkaline treatment liquid for a semiconductor substrate, which use adsorption purification means that can purify various alkaline treatment liquids to be used for treating semiconductor substrates for various purposes so as to have an ultrahigh purity, in particular, an Fe concentration in a ppq region, and that is excellent in chemical resistance and mechanical strength. The adsorption purification means is purification means for an alkaline treatment liquid for treating a semiconductor substrate for various purposes at the time of producing, for example, a semiconductor substrate or a semiconductor device.

Abstract: Provided is an electrode for electrolysis with excellent corrosion resistance and durability which can be used sustainably in the production of a high-purity quaternary ammonium hydroxide by the electrolysis of a quaternary ammonium inorganic acid salt in an electrolytic cell partitioned by a cation exchange membrane on a commercial scale with reduced electric power consumption at low cost. The electrode for electrolysis is useful for the production of a quaternary ammonium hydroxide by the electrolysis of a quaternary ammonium inorganic acid salt in an electrolytic cell partitioned by a cation exchange membrane and comprises an electrode base material of an electrically conductive metal, an electrode active layer containing an electrode active material covering the electrode base material, and an intermediate layer of a mixed oxide of an oxide of at least one kind of metal selected from In, Ir, Ta, Ti, Ru, and Nb and an oxide of Sn disposed between the electrode base material and the electrode active layer.

Abstract: Disclosed is a uniformly-dispersed photocatalyst coating liquid having excellent dispersion stability of titanium oxide particles which have photocatalytic activity, which coating liquid places no burden on the environment while being excellent in handling properties. In addition, this uniformly-dispersed photocatalyst coating liquid enables to form a photocatalyst coating film, which is excellent in photocatalytic activities (antifouling property and/or antibacterial property), transparency and durability, on the surface of a base when applied thereto. Also disclosed are a method for producing such a uniformly-dispersed photocatalyst coating liquid, and a photocatalytically active composite material obtained by using such a uniformly-dispersed photocatalyst coating liquid.

Abstract: Provided is an electrode for electrolysis with excellent corrosion resistance and durability which can be used sustainably in the production of a high-purity quaternary ammonium hydroxide by the electrolysis of a quaternary ammonium inorganic acid salt in an electrolytic cell partitioned by a cation exchange membrane on a commercial scale with reduced electric power consumption at low cost. The electrode for electrolysis is useful for the production of a quaternary ammonium hydroxide by the electrolysis of a quaternary ammonium inorganic acid salt in an electrolytic cell partitioned by a cation exchange membrane and comprises an electrode base material of an electrically conductive metal, an electrode active layer containing an electrode active material covering the electrode base material, and an intermediate layer of a mixed oxide of an oxide of at least one kind of metal selected from In, Ir, Ta, Ti, Ru, and Nb and an oxide of Sn disposed between the electrode base material and the electrode active layer.

Abstract: To provide an abrasive slurry having high dispersion stability, including: abrasive fine particles made of one or more kinds of oxides; colloidal fine particles made of colloidal oxide with an average particle size smaller than an average particle size of the abrasive fine particles; and a dispersion medium in which the abrasive fine particles and the colloidal fine particles are dispersed, and a manufacturing method for a substrate as an inorganic substrate, including polishing the substrate using the abrasive slurry. An abrasive slurry according to the present invention keeps high dispersion stability for a long time and shows a satisfactory redispersion property, which can eliminate a problem about precipitation/aggregation as much as possible and can be used as a dispersant-free abrasive containing absolutely no organic dispersant.

Abstract: The copper-based metal polishing composition causes Cu or Cu alloy not to be dissolved at all in immersing Cu or Cu alloy therein, and makes it possible to polish Cu or Cu alloy at a high rate in polishing treatment. Such a copper-based metal polishing composition comprises a water-soluble first organic acid capable of reaction with copper to produce a copper complex compound which is substantially insoluble in water and has a mechanical strength lower than that of copper, at least one second organic acid selected from an organic acid having a single carboxyl group and a single hydroxyl group and oxalic acid, an abrasive grain, an oxidizing agent, and water.

Abstract: To provide an abrasive slurry having high dispersion stability, including: abrasive fine particles made of one or more kinds of oxides; colloidal fine particles made of colloidal oxide with an average particle size smaller than an average particle size of the abrasive fine particles; and a dispersion medium in which the abrasive fine particles and the colloidal fine particles are dispersed, and a manufacturing method for a substrate as an inorganic substrate, including polishing the substrate using the abrasive slurry. An abrasive slurry according to the present invention keeps high dispersion stability for a long time and shows a satisfactory redispersion property, which can eliminate a problem about precipitation/aggregation as much as possible and can be used as a dispersant-free abrasive containing absolutely no organic dispersant.

Abstract: The copper-based metal polishing composition causes Cu or Cu alloy not to be dissolved at all in immersing Cu or Cu alloy therein, and makes it possible to polish Cu or Cu alloy at a high rate in polishing treatment. Such a copper-based metal polishing composition comprises a water-soluble first organic acid capable of reaction with copper to produce a copper complex compound which is substantially insoluble in water and has a mechanical strength lower than that of copper, at least one second organic acid selected from an organic acid having a single carboxyl group and a single hydroxyl group and oxalic acid, an abrasive grain, an oxidizing agent, and water.

Abstract: The copper-based metal polishing composition causes Cu or Cu alloy not to be dissolved at all in immersing Cu or Cu alloy therein, and makes it possible to polish Cu or Cu alloy at a high rate in polishing treatment. Such a copper-based metal polishing composition comprises a water-soluble first organic acid capable of reaction with copper to produce a copper complex compound which is substantially insoluble in water and has a mechanical strength lower than that of copper, at least one second organic acid selected from an organic acid having a single carboxyl group and a single hydroxyl group and oxalic acid, an abrasive grain, an oxidizing agent, and water.

Abstract: An apparatus of this invention for supplying an abrasive for use in the manufacture of semiconductors comprises a storage tank of the abrasive and a supply line for guiding the abrasive from the storage tank to a nozzle for supplying the abrasive to an object to be polished and said storage tank or supply line is provided with a device for furnishing ultrasonic wave to sonicate the abrasive. A process of this invention for supplying an abrasive for use in the manufacture of semiconductors comprises sonicating the abrasive by ultrasonic wave before supplying it to an object to be polished. The apparatus and process of this invention for supplying an abrasive for use in the manufacture of semiconductors make it possible to supply an abrasive containing a minimized amount of abnormally agglomerated particles to the surface of an object to be polished in the manufacturing step of semiconductors and improve the yield of polished products.

Abstract: A process which comprises reacting a high molecular weight polyorganosiloxane or a composition containing the same with an alkoxysilane and/or a partially hydrolyzed condensate thereof at a temperature of lower than 300.degree. C. in the presence of an alcoholate compound and recovering the resulting organoalkoxysilane and, in addition thereto, at least one of a distillable polyorganosiloxane low molecular weight compound, a non-volatile liquid polyorganosiloxane and a silica; and a process which comprises reacting a high molecular weight polyorganosiloxane or a composition containing the same with an alcoholate compound at a temperature of 50.degree. to 150.degree. C. in an anhydrous state and recovering the resulting distillable polyorganosiloxane low molecular weight compound and, in addition thereto, at least one of an organoalkoxysilane and a non-volatile liquid polyorganosiloxane.

Abstract: The invention is a method of processing a waste liquid containing at least an organic quaternary ammonium hydroxide. The waste liquid is brought into contact with a cation-exchanging material so as to make the organic quaternary ammonium ions adsorbed by the material to thereby remove the ions from the liquid (adsorbing step), and optionally the cation-exchanged water obtained by the contact is again processed to separate and remove resist peelings and surfactants therefrom. The invention is also a method of processing the organic quaternary ammonium hydroxide-containing waste liquid for recovering a valuable substance of the organic quaternary ammonium hydroxide therefrom.

Abstract: This invention relates to a process for preparing dialkyl carbonates by the reaction of one kind or a mixture of two or more kinds selected from urea, methyl carbamate and ethyl carbamate with methanol and/or ethanol in the presence of a catalyst under pressure at 100.degree. to 250.degree. C. and the process does not use poisonous phosgene or carbon monoxide as raw material and readily yields dimethyl carbonate and diethyl carbonate in simple equipment.

Abstract: The invention is a method of processing a waste liquid containing at least an organic quaternary ammonium hydroxide. The waste liquid is brought into contact with a cation-exchanging material so as to make the organic quaternary ammonium ions adsorbed by the material to thereby remove the ions from the liquid (adsorbing step), and optionally the cation-exchanged water obtained by the contact is again processed to separate and remove resist peelings and surfactants therefrom. The invention is also a method of processing the organic quaternary ammonium hydroxide-containing waste liquid for recovering a valuable substance of the organic quaternary ammonium hydroxide therefrom.

Abstract: A distillable liquid containing non-volatile impurities is freed of those impurities by boiling the liquid to form vapors of the liquid, passing the vapors through a packed column heated to a temperature such that liquid entrained in the vapors is completely vaporized and the non-volatile impurities remain in the packed column, and condensing the vapors from the column.

Abstract: A method of producing synthetic silica which is characterized by hydrolyzing a tetraalkoxysilane under a basic condition in the presence of an ammonium salt.

Abstract: An aqueous quaternary ammonium hydroxide solution is produced by a method which is characterized by the steps of synthesizing an inorganic acid salt of quaternary ammonium by the reaction of a trialkylamine with a dialkyl carbonate and the electrolyzing the inorganic acid salt with an electrolytic cell using a cation-exchange membrane as a diaphragm thereby producing quaternary ammonium hydroxide.