Abstract: A tube-type ozone generator 1 including an ozone generation unit 30A is provided. The ozone generation unit 30A includes an outer electrode tube 31 and an inner electrode tube 32 provided inside the outer electrode tube with a discharge gap 36 interposed between the outer and inner electrode tubes 31 and 32. The inner electrode tube 32 has a dielectric tube 33 and a cylindrical electrode 34 being in close contact with an inner circumferential surface of the dielectric tube 33. The electrode 34 is removably disposed inside the dielectric tube 33.

Abstract: A tube-type ozone generator 1 including an ozone generation unit 30A is provided. The ozone generation unit 30A includes an outer electrode tube 31 and an inner electrode tube 32 provided inside the outer electrode tube with a discharge gap 36 interposed between the outer and inner electrode tubes 31 and 32. The inner electrode tube 32 has a dielectric tube 33 and a cylindrical electrode 34 being in close contact with an inner circumferential surface of the dielectric tube 33. The electrode 34 is removably disposed inside the dielectric tube 33.

Abstract: Oxygen gas having a high purity is supplied to an electric discharge type ozonizer to generate ozone. An ozone density is prevented from decreasing without the use of nitrogen gas by adding moisture to the high-purity oxygen gas via a humidifier when the high-purity oxygen gas is supplied to an ozonizer from an oxygen gas source. Through the addition, the moisture volume in the high-purity oxygen gas supplied to the ozonizer is adjusted to be within the range of 0.05-40 ppm.

Abstract: The method of polishing a copper layer of a substrate is capable of improving a stock removal rate, etc. The method comprises the steps of: supplying a substrate onto an polishing pad of an polishing plate with a copper layer facing the polishing pad; pressing the substrate onto the polishing pad, with a backing pad, by a press head; relatively rotating the press head with respect to the polishing plate, with supplying polishing slurry onto the polishing pad. The backing pad is made of a material whose Asker C hardness is 75-95 and whose compressibility is 10% or less. The polishing slurry includes a chelating agent for chelating copper, an etching agent for etching the surface of copper layer, an oxidizing agent for oxidizing the surface of copper layer, and water.

Abstract: The method of polishing a copper layer of a substrate is capable of improving a stock removal rate, etc. The method comprises the steps of: supplying a substrate onto an polishing pad of an polishing plate with a copper layer facing the polishing pad; pressing the substrate onto the polishing pad, with a backing pad, by a press head; relatively rotating the press head with respect to the polishing plate, with supplying polishing slurry onto the polishing pad. The backing pad is made of a material whose Asker C hardness is 75-95 and whose compressibility is 10% or less. The polishing slurry includes a chelating agent for chelating copper, an etching agent for etching the surface of copper layer, an oxidizing agent for oxidizing the surface of copper layer, and water.

Abstract: There is disclosed an optical disk unit. Optical parts, including a laser unit and objective, are integrally mounted on a bobbin, and focusing coils and tracking and feed coils are mounted on the bobbin. The bobbin is resiliently supported, and is slidable along guide shafts extending radially of an optical disk loaded on the optical disk unit. The bobbin is moved by the focusing coils and the tracking and feed coils, thereby effecting a focusing drive, a tracking drive and a feed drive. With this construction, the optical disk unit can be compact in size, and light in weight.

Abstract: A dot-matrix impact printer includes a print head in a housing for printing a recording sheet fed around a platen. The recording sheet is pressed against the platen by a sheet presser roller. A roller cover or a flap is disclosed as a sound insulating wall closely to the sheet presser roller and has an edge held against the housing. The space above the print head is closed by the housing, the platen, the sheet presser roller, and the platen, so that the impact noise produced when the printer is in operation will not leak out of the housing, while at the same time the recording sheet fed around the platen is not blocked by the closure mechanism.