CIRCUIT SUBSTRATE WITH BUILT-IN CAPACITOR, METHOD OF MANUFACTURING THE CIRCUIT SUBSTRATE, AND SEMICONDUCTOR DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device which can reduce the switching noise, without having to lower mounting density by building a decoupling capacitor for enhancing the capacitance density to a circuit substrate, which is suitable for an interposer on the occasion of mounting a semiconductor chip to the wiring substrate. SOLUTION: A capacitor, having a conductive via within a substrate via an insulation layer and using the base substrate consisting of a conductive member as a part of electrode, is formed on a support substrate having an internal conductive via and connecting terminals are provided at the base substrate and one surface of the support substrate. Moreover, after the capacitor is formed on the base substrate, the base substrate is attached to the supporting substrate and the conductive via is formed within the base substrate.