| abstract |
An adhesive sheet comprising a pressure-sensitive adhesive layer and a substrate layer, wherein the strength of adhesion between the pressure-sensitive adhesive layer and the substrate layer is controlled by means of irradiation with a radiation and the pressure-sensitive adhesive layer comprises the following ingredients: (a) a thermoplastic resin, (b) a heat-polymerizable ingredient, and (c) a compound which generates a base upon irradiation with the radiation. The adhesive sheet satisfies the following inconsistent requirements: it should have tackiness sufficient to keep semiconductor elements held thereon during dicing and, upon subsequent irradiation with a radiation for regulating the strength of adhesion between the pressure-sensitive adhesive layer and the substrate, come to have such low tackiness that it does not damage the elements during pickup. |