Patent ID: 7456065
Filing Date: 2008-11-25
Classification: H01L

Abstract:
1. A method for manufacturing a dynamic random access memory (DRAM) cylindrical capacitor, comprising: providing a substrate having a polysilicon plug formed therein; forming a dielectric layer having an opening formed therein, wherein the opening exposes the polysilicon plug; forming an amorphous silicon layer over the substrate to cover the surface of the dielectric layer and fill the opening; anisotropically etching the amorphous silicon layer to remove portions of the amorphous silicon layer disposed outside the opening and a bottom of the opening in order to form an amorphous silicon spacer on the sidewall of the opening and expose a portion of the polysilicon plug; partially removing a top portion of the exposed polysilicon plug; using a seeding method to grow a hemispherical silicon grain (HSG) layer on a surface of the amorphous silicon spacer; forming a capacitor dielectric layer on a surface of the HSG layer; and forming a conductive layer on the capacitor dielectric layer.