US Patent 7884459 Semiconductor device suitable for a stacked structure

A semiconductor device is provided that forms a three-dimensional semiconductor device having semiconductor devices stacked on one another. In this semiconductor device, a hole is formed in a silicon semiconductor substrate that has an integrated circuit unit and an electrode pad formed on a principal surface on the outer side. The hole is formed by etching, with the electrode pad serving as an etching stopper layer. An embedded electrode is formed in the hole. This embedded electrode serves to electrically lead the electrode pad to the principal surface on the bottom side of the silicon semiconductor substrate.