Composition for curable resin, cured product of said composition, production method for said composition and said cured product, and semiconductor device

A method of producing a curable resin composition, the method comprising the steps of:

• mixing
• (A) a multifunctional benzoxazine compound having at least two benzoxazine rings, the multifunctional benzoxazine compound being at least one multifunctional benzoxazine compound selected from
• (1) a multifunctional benzoxazine compound having a structural unit of formula (1)
• wherein R represents a linear alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, where the aryl group optionally has halogen or a linear alkyl group having 1 to 12 carbon atoms, as a substituent, and each Z represents hydrogen, a hydrocarbon group having 1 to 8 carbon atoms and/or a linking group and is optionally the same or different, wherein at least one Z represents a linking group, and benzoxazine rings are linked by the linking group;
• and
• (2) a multifunctional benzoxazine compound represented by a structure of formula (2)
• wherein L represents a divalent organic group having 1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms, and the organic group and the alkylene group optionally comprise oxygen and/or sulfur,
• (B) an epoxy compound having at least one norbornane structure and at least two epoxy groups, wherein the epoxy compound is at least one compound selected from
• (C) a trisphenolmethane type epoxy compound, and
• (D) a curing agent, to obtain a mixture;
• and
• processing the mixture into a powdery, pelletized, or granular curable resin composition,
• wherein the curable resin composition has a compounding ratio between component (A) and a total of component (B) and component (C) of 5 parts by mass or more and 150 parts by mass or less, where the compounding ratio is determined by the total of component (B) and component (C) based on 100 parts by mass of component (A), and
• wherein the curable resin composition has an epoxy equivalent ratio of 0.5 or more and 1.5 or less, where the epoxy equivalent ratio is determined by [total number of epoxy groups in components (B) and (C)]/[number of cyanato groups in component (A)+number of hydroxyl groups in component (D)].