Abstract: The base film of the invention is a base film of a pressure-sensitive adhesive sheet for laminating onto a semiconductor wafer composed of: (A) a layer of a cured product in which a composition including a polyether polyol urethan(meth)acrylate oligomer and an energy ray curable monomer is cured by energy ray irradiation, and (B) a thermoplastic resin layer. The present invention, by using a surface protection sheet, protects a circuit side of a wafer with bumps, prevents collapse of bumps on the circuit side when grinding the back surface, and prevents generation of dimples or cracks on the grinding surface.

Abstract: To prevent bumps on the circuit side of a bump-bearing wafer from getting crushed when grinding the back side of said wafer while protecting the circuit side with a surface-protection sheet, and also to minimize the formation of dimples and cracks on the side being ground. [Solution] This base film for a pressure-sensitive adhesive sheet bonded to a semiconductor wafer comprises: (A) a layer obtained by using energy rays to cure a formulation containing a urethane (meth)acrylate oligomer and a thiol-group-containing compound; and (B) a layer comprising a thermoplastic resin.

Abstract: To prevent bumps on the circuit side of a bump-bearing wafer from getting crushed when grinding the back side of said wafer while protecting the circuit side with a surface-protection sheet, and also to minimize the formation of dimples and cracks on the side being ground. [Solution] This base film for a pressure-sensitive adhesive sheet bonded to a semiconductor wafer comprises: (A) a layer obtained by using energy rays to cure a formulation containing a urethane (meth)acrylate oligomer and a thiol-group-containing compound; and (B) a layer comprising a thermoplastic resin.

Abstract: The base film of the invention is a base film of a pressure-sensitive adhesive sheet for laminating onto a semiconductor wafer composed of: (A) a layer of a cured product in which a composition including a polyether polyol urethan(meth)acrylate oligomer and an energy ray curable monomer is cured by energy ray irradiation, and (B) a thermoplastic resin layer. The present invention, by using a surface protection sheet, protects a circuit side of a wafer with bumps, prevents collapse of bumps on the circuit side when grinding the back surface, and prevents generation of dimples or cracks on the grinding surface.