A Mechanically Enhanced Storage Node For Virtually Unlimited Height (Mesh) Capacitor Aiming At Sub 70nm Drams

Fully reliable lean-free stacked capacitor, with the meshes of the supporter made Of Si3N4, has been successfully developed on 80nm COB DRAM application. This novel process terminates persistent problems caused by mechanical instability of storage node with high aspect ratio. With Mechanically Enhanced Storage node for virtually unlimited Height (MESH), the cell capacitance over 30fF/cell has been obtained by using conventional MIS dielectric with an equivalent 2.3nm oxide thickness. This inherently lean-free capacitor makes it possible extending the existing MIS dielectric technology to sub-70nm OCS (one cylindrical storage node) DRAMs.