Method of making a trench capacitor

摘要

A method of making a trench capacitor including the following steps: forming a first trench of predetermined depth into a semiconductor substrate; forming an electrode plate on the side-wall of a bottom of the first trench; forming a dielectric layer on the electrode plate; forming a first conductive portion on the dielectric layer, wherein the first conductive portion fills the bottom of the first trench to form a second trench; forming an insulation layer to fill the bottom portion of the second trench to make a third trench in the second trench; forming a conductive spacer along the side-wall of the third trench; etching the insulation layer using the conductive spacer as a mask to form a forth trench; and then filling the forth trench with a conductive material.