Abstract: The invention provides a connecting structure for a flip-chip semiconductor package in which cracking and delamination are inhibited or reduced to improve reliability, and in which the potential range of designs is expanded for the inner circuitry of circuit boards and the inductance is reduced. The invention is a connecting structure for a flip-chip semiconductor package, including: a circuit board having a core layer and at least one build-up layer; a semiconductor element connected via metal bumps to the circuit board; and a sealing resin composition with which gaps between the semiconductor element and circuit board are filled, wherein a cured product of the sealing resin composition has a glass transition temperature between 60° C. and 150° C. and a coefficient of linear expansion from room temperature to the glass transition temperature being between 15 ppm/° C. and 35 ppm/° C., a cured product of the build-up layer has a the glass transition temperature of at least 170° C.

Abstract: The invention provides a connecting structure for a flip-chip semiconductor package in which cracking and delamination are inhibited or reduced to improve reliability, and in which the potential range of designs is expanded for the inner circuitry of circuit boards and the inductance is reduced. The invention is a connecting structure for a flip-chip semiconductor package, including: a circuit board having a core layer and at least one build-up layer; a semiconductor element connected via metal bumps to the circuit board; and a sealing resin composition with which gaps between the semiconductor element and circuit board are filled, wherein a cured product of the sealing resin composition has a glass transition temperature between 60° C. and 150° C. and a coefficient of linear expansion from room temperature to the glass transition temperature being between 15 ppm/° C. and 35 ppm/° C., a cured product of the build-up layer has a the glass transition temperature of at least 170° C.

Abstract: A polybenzoxazole precursor having recurring units represented by the following general formula (1) and a polybenzoxazole resin having a structure obtained by cyclizing the polybenzoxazole precursor: wherein n denotes an integer of 1-1000, and (i) when X is selected from bivalent aromatic groups represented by the general formulas (2)-(4) defined in the specification each having two OR groups (Rs each denotes H or a monovalent organic group and may be the same or different), and the amide group in the formula (1) and the OR group respectively bond to the adjacent carbon atoms of the aromatic group, Y denotes a bivalent organic group containing fluorine; and (ii) when Y is selected from bivalent aromatic groups represented by the general formulas (5)-(7) defined in the specification, X denotes a bivalent aromatic group containing fluorine and having two OR groups (Rs each denotes H or a monovalent organic group and may be the same or different), and the amide group in the formula (1) and the

Abstract: Polybenzoxazole precursors are used to prepare resins with good electrical characteristics and thermal characteristics as well as low water absorption.