Semiconductor integrated circuit device with trench capacitor and method of manufacturing the same

摘要

A semiconductor integrated circuit device includes a p-silicon substrate, an n-buried layer formed in the substrate to divide the substrate into an upper region and a lower region, a trench formed from the surface of the substrate to the lower region of the substrate through the buried layer, and an electrode formed in the trench. The electrode forms an n-inversion layer using the buried layer as a carrier source, in the lower region of the semiconductor substrate by a field effect. The n-inversion layer constitutes a capacitor together with the electrode.