Abstract: Disclosed is a pressure-sensitive adhesive sheet for use in processing a product such a semiconductor wafer. To provide a pressure-sensitive adhesive sheet that provides a minimized number of broken semiconductor wafers during the process of polishing them and that produces a less curl of the wafer due to the residual stress of the pressure-sensitive adhesive sheet, the pressure-sensitive adhesive sheet includes a composite film formed from a composition containing a urethane polymer and a vinyl polymer as effective components, a first film comprising a material different from that of the composite film, and a pressure-sensitive adhesive layer, in which the pressure-sensitive adhesive sheet has a modulus of 9 N/mm2 or more and 250 N/mm2 or less when an oblong piece of the pressure-sensitive adhesive sheet with a width of 20 mm is bent at a radius of curvature of 3.0 mm.

Abstract: An ultraviolet curing pressure-sensitive adhesive sheet prepared by forming an ultraviolet curing pressure-sensitive adhesive layer on at least one surface of a substrate film and adhering a separator to the surface of the ultraviolet curing pressure-sensitive adhesive layer, wherein the separator has an ultraviolet transmittance at a wavelength of 300 to 400 nm of 65% or lower. The separator is obtained by forming a layer containing an ultraviolet absorber on the surface of the substrate film opposite the surface adhering to the pressure-sensitive adhesive layer or incorporating an ultraviolet absorber in the film. The ultraviolet curing pressure-sensitive adhesive sheet is useful as a semiconductor-protective pressure-sensitive adhesive sheet and a semiconductor wafer-fixing sheet, which can be used without causing a curing reaction with the exposure of a slight amount of ultraviolet rays from a surrounding environment at the standby for adhering wafers.