Patent ID: 7122424
Filing Date: 2006-10-17
Classification: H01L

Abstract:
1. A method for making improved bottom electrodes for crown-shaped capacitors on a substrate comprising the steps of: providing said substrate having device areas; providing an insulating layer with openings formed therein, wherein the openings are formed in a central region and a edge region of the device areas; depositing a conformal first conducting layer on said insulating layer and in said openings; forming a blanket sacrificial layer sufficiently thick to fill said openings; partially removing said sacrificial layer to form a planar surface across said substrate and to expose said first conducting layer on top surface of said insulating layer while leaving portions of said sacrificial layer in said openings, wherein the sacrificial layer left in said openings at the central region and the edge region of the device areas have a substantially same height; recessing said first conducting layer in said openings to form said bottom electrodes; removing said sacrificial layer in said openings; forming a conformal capacitor dielectric film over said bottom electrodes and on said substrate; and forming a second conducting layer in said openings to form self-aligned top electrodes.