Abstract: A polishing pad is provided with a compression elastic modulus of 0.17 MPa or more and 0.32 MPa or less produced by preparing a nonwoven fabric formed of bundles of ultrafine fibers with an average monofilament diameter of 3.0 ?m or more and 8.0 ?m or less, preparing a polishing pad base by impregnating the nonwoven fabric with a polyurethane based elastomer in an amount of 20 mass % or more and 50 mass % or less relative to the mass of the polishing pad base, and laminating the polishing pad base with a porous polyurethane layer containing wet-solidified polyurethane as primary component which has openings with an average opening diameter of 10 ?m or more and 90 ?m or less in its surface to serve as polishing surface layer.

Abstract: A polishing pad is provided with a compression elastic modulus of 0.17 MPa or more and 0.32 MPa or less produced by preparing a nonwoven fabric formed of bundles of ultrafine fibers with an average monofilament diameter of 3.0 ?m or more and 8.0 ?m or less, preparing a polishing pad base by impregnating the nonwoven fabric with a polyurethane based elastomer in an amount of 20 mass % or more and 50 mass % or less relative to the mass of the polishing pad base, and laminating the polishing pad base with a porous polyurethane layer containing wet-solidified polyurethane as primary component which has openings with an average opening diameter of 10 ?m or more and 90 ?m or less in its surface to serve as polishing surface layer.

Abstract: A polishing pad forms a planar surface on glass, semiconductors, dielectric material/metal composites and integrated circuits, as well as a polishing apparatus where it is difficult for the surface of the substrate to be scratched, the state of polishing can be accurately measured optically during polishing, and whether or not the entire surface of the workpiece is uniformly polished can be measured.

Abstract: A polishing pad which comprises a laminate of an abrasive layer with a cushioning layer. The abrasive layer has a Microrubber A hardness of 75 degrees or higher and a thickness of 0.8-3.0 mm. The cushioning layer comprises an unfoamed elastomer and has a thickness of 0.05-1.5 mm. The abrasive layer has at least two kinds of grooves formed in the surface. One of the two kinds of grooves is first grooves and the other is second grooves. The first grooves each has a groove width of 0.5-1.2 mm, and has a groove pitch of 7.5-50 mm. The second grooves each has a groove width of 1.5-3 mm, and has a groove pitch of 20-50 mm. Each of the first grooves and each of the second grooves are open to side edge faces of the abrasive layer.

Abstract: A polishing pad forms a planar surface on glass, semiconductors, dielectric material/metal composites and integrated circuits, as well as a polishing apparatus where it is difficult for the surface of the substrate to be scratched, the state of polishing can be accurately measured optically during polishing, and whether or not the entire surface of the workpiece is uniformly polished can be measured.

Abstract: It is an object of the present invention to provide a windowed polishing pad or a platen hole cover which is used to form planar surfaces in glass, semiconductors, dielectric/metal composites, integrated circuits, etc.; a polishing apparatus including the windowed polishing pad or the platen hole cover; a method for fabricating a semiconductor device using the polishing apparatus; and a polishing method, in which the number of scratches occurring on the surface of the substrate is small, and the polished state can be optically measured satisfactorily during polishing.

Abstract: The present invention relates to a polishing pad which is characterized in that it is of micro rubber A-type hardness at least 80°, has closed cells of average cell diameter no more than 1000 &mgr;m, is of density in the range 0.4 to 1.1 and contains polyurethane and polymer produced from a vinyl compound. When planarizing local unevenness on a semiconductor substrate with the polishing pad relating to the present invention, the polishing rate is high, the global step height is low, dishing does not readily occur at the metallic interconnects, clogging and permanent set of the surface layer region do not readily occur and the polishing rate is stable.

Abstract: The present invention relates to a polishing pad which is characterized in that it has a polishing layer of rubber A-type microhardness at least 80° and a cushioning layer of bulk modulus at least 40 MPa and tensile modulus in the range 0.1 MPa to 20 MPa, and to a polishing device which is characterized in that a semiconductor substrate is fixed to the polishing head, and an aforesaid polishing pad is fixed to the polishing platen so that the polishing layer faces the semiconductor substrate, and by rotating the aforesaid polishing head or the polishing platen, or both, the semiconductor substrate is polished.

Abstract: A composite membrane excelling in organic solvent resistance, heat resistance and organic vapor resistance is disclosed. The composite membrane of the present invention comprises a porous membrane including as a major constituent a polymer having a repeating unit represented by the formula (I)--Ph--S--Ph--SO.sub.2).sub.n (I)(wherein Ph represents phenyl group, n represents a natural number) and an active layer formed on said porous membrane. The composite membrane of the present invention may be used as a composite membrane for pervaporation, gas separation membrane and as a reverse osmosis membrane.

Abstract: A gas separation membrane with excellent gas separation properties is disclosed. The gas separation membrane is substantially free from pinholes and consists essentially of a crosslinked polyolefin or a crosslinked polyarylene oxide. This gas separation membrane is produced by evaporating a solution containing a polyolefin or a polyarylene oxide having an active functional group which can form crosslinking site therebetween or which can react with a crosslinking agent to form a crosslinking site.