Patent ID: 7332393
Filing Date: 2008-02-19
Classification: H01L

Abstract:
1. A method for fabricating a cylindrical capacitor, comprising the steps of: providing a substrate having a plug formed therein; sequentially forming a first dielectric layer, a structure layer, a second dielectric layer and an etching stop layer over the substrate; forming a hole passing through the first dielectric layer, the structure layer, the second dielectric layer and the etching stop layer such that the hole exposes the plug; forming a conductive layer over the substrate to cover the etching stop layer and an inner surface of the hole; removing a portion of the conductive layer at the top of the hole to expose a portion of the second dielectric layer such that a remaining portion of the conductive layer serves as a bottom electrode; performing an isotropic etching process to remove a portion of the exposed second dielectric layer to form an opening at the top of the hole; removing the etching stop layer; filling the opening and the hole with a material layer; removing the second dielectric layer; performing an anisotropic etching process on the structure layer using the material layer as a etching mask to expose a portion of the first dielectric layer; removing the first dielectric layer so that the bottom electrode is completely exposed; forming a capacitor dielectric layer on the surface of the bottom electrode; and forming a top electrode on the surface of the capacitor dielectric layer.