Patent ID: 7335933

Claim:
A trench capacitor, comprising: a substrate having a trench; a conducting layer filling said trench; a first capacitor dielectric layer between a surface of said trench and said conducting layer, wherein the first capacitor dielectric layer continuously extends from inside of the trench to an upper surface of the substrate and is formed with an oxide/nitride stacked layer; a protruding electrode on said substrate around said trench and covering a junction of said trench and said substrate, said protruding electrode having an upper surface and a sidewall; a second capacitor dielectric layer between said protruding electrode and said substrate, said substrate around said first and second capacitor dielectric layers being a bottom electrode; and a conducting structure electrically connecting said protruding electrode and said conducting layer, wherein said conducting layer, said protruding electrode, and said conducting structure serve as an upper electrode, and wherein said conducting structure electrically connects said protruding electrode by contacting solely the upper surface of said protruding electrode.