MULTILAYER PRINTED WIRING BOARD

摘要

A multilayer printed wiring board is equipped with a core board 20, a build-up layer 30 formed on the core board 20 so as to have a conductor pattern 32 on the upper surface thereof, a low-elasticity layer 40 formed on the build-up layer 30, lands 52 that are provided on the upper surface of the low-elasticity layer 40 and connected to an IC chip 70 via solder bumps 66, and conductor posts 50 that penetrate through the low-elasticity layer 40 and electrically connect the lands 52 to the conductor pattern 32. The low-elasticity layer 40 is formed of resin composition containing epoxy resin, phenol resin, cross-linked rubber particles and a hardening catalyst.