Patent ID: 6358837
Filing Date: 2002-03-19
Classification: H01L

Abstract:
A method of forming and electrically connecting an elongated vertically oriented trench capacitor having metal upper and lower capacitor plates extending in an opening through an inter-layer dielectric positioned between a lower generally-planar interconnect layer of conductors and an upper generally-planar interconnect layer of conductors in an IC having a substrate, the lower interconnect layer separated from the substrate by a layer of dielectric material, comprising the steps of:connecting a lower end of the lower capacitor plate to a conductor of the lower interconnect layer at a lower end of the opening; extending an upper end of the lower capacitor plate beyond an upper surface of the inter-layer dielectric; chemical mechanical polishing the extending upper end down flush with the upper surface of the inter-layer dielectric; covering the flush upper end with dielectric material; forming the upper capacitor plate on top of the dielectric material covering the flush upper end; chemical mechanical polishing an upper surface of the upper capacitor plate to a planar surface; and forming at least one electrical conductor of the upper interconnect layer in contact with the planar upper surface of the upper capacitor plate.