Trench capacitor with pillar

摘要

A trench capacitor having a conductive pillar in a central region of a trench. A first plate of the capacitor includes the substrate in the lower portion of the trench and the conductive pillar. The capacitor dielectric is disposed over the conductive pillar and the sidewalls of the trench lower portion. A second plate of the capacitor is a conductive material disposed over the dielectric material. The conductive pillar increases the surface area of the capacitor plates, increasing the capacitance of the capacitor. A top portion of the conductive pillar may be hollow, further increasing the surface area of the capacitor plates.