3D via capacitor with a floating conductive plate for improved reliability

摘要

The present invention provides a 3D via capacitor and a method for forming the same. The capacitor includes an insulating layer on a substrate. The insulating layer has a via having sidewalls and a bottom. A first electrode overlies the sidewalls and at least a portion of the bottom of the via. A first high-k dielectric material layer overlies the first electrode. A first conductive plate is over the first high-k dielectric material layer. A second high-k dielectric material layer overlies the first conductive plate and leaves a remaining portion of the via unfilled. A second electrode is formed in the remaining portion of the via. The first conductive plate is substantially parallel to the first electrode and is not in contact with the first and second electrodes. An array of such 3D via capacitors is also provided.