Abstract: The present invention relates to a process for producing an interpenetrating polymer network structure, which comprises the steps of impregnating a polymer molding with a radical polymerizable composition containing an ethylenically unsaturated compound and a radical polymerization initiator; and polymerizing the ethylenically unsaturated compound in a swollen state of the polymer molding impregnated with the radical polymerizable composition; wherein a chain transfer agent and/or a radical polymerization inhibitor are added to the radical polymerizable composition and/or the polymer molding before impregnating the polymer molding with the radical polymerizable composition. According to the present invention, a highly uniform interpenetrating polymer network structure can be obtained.

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: The present invention relates to a process for producing an interpenetrating polymer network structure, which comprises the steps of impregnating a polymer molding with a radical polymerizable composition containing an ethylenically unsaturated compound and a radical polymerization initiator; and polymerizing the ethylenically unsaturated compound in a swollen state of the polymer molding impregnated with the radical polymerizable composition; wherein a chain transfer agent and/or a radical polymerization inhibitor are added to the radical polymerizable composition and/or the polymer molding before impregnating the polymer molding with the radical polymerizable composition. According to the present invention, a highly uniform interpenetrating polymer network structure can be obtained.

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.