Method of fabricating cup-shape cylindrical capacitor of high density DRAMS

A method of fabricating at least one cup-shape capacitor of a DRAM cell, said method comprising the steps of:

• (a) forming isolation regions and MOSFET structures on a silicon substrate, wherein said MOSFET comprises of gate oxide, gate electrode and drain/source regions;
• (b) continuously forming a first dielectric and a second dielectric layers overlaying the surface of said silicon substrate;
• (c) partially etching said first dielectric and said second dielectric layers to open cell contact windows for said source regions of said MOSFET;
• (d) forming a first polysilicon layer overlaying said second dielectric layer and filling into said cell contact windows;
• (e) forming a third dielectric layer overlaying said first polysilicon layer, and defining third dielectric crowns;
• (f) depositing a second polysilicon layer overlaying said first polysilicon layer and said third dielectric crowns;
• (g) anisotropically etching said second polysilicon layer to construct the storage node of said capacitor which consists of the remaining said first polysilicon and said second polysilicon;
• (h) removing said third dielectric crowns.
• (i) forming a capacitor dielectric layer overlaying said storage node of said capacitor;
• and
• (j) forming a third polysilicon layer overlaying said capacitor dielectric layer as top electrode of said capacitor.