CIRCUIT BOARD STRUCTURES AND METHODS OF FABRICATING THE SAME

A method of fabricating a circuit board structure is provided. The method includes providing a core substrate; forming an insulation layer on the core substrate; forming a patterned metal layer on the insulation layer, wherein the patterned metal layer includes a wiring layer and a pad; forming a first metal pillar on the pad, wherein the first metal pillar has a top surface; and forming a first solder resist layer on the patterned metal layer and the first metal pillar, wherein the first solder resist layer has a first opening exposing the first metal pillar, and the first opening has a bottom surface, wherein the top surface of the metal pillar is higher than or equal to the bottom surface of the first opening.