Structure and method for manufacturing trench capacitance

US7858485B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Huilong Zhu · Poughkeepsie, US
• Babar A. Khan · Ossining, US
• Xi Li · Somers, US
• Joyce C. Liu · Carmel, US
• Thomas A. Wallner · Pleasant Valley, US

Key dates

• Filing date: Aug 14, 2008
• Grant date: Dec 28, 2010
• Expiry date: Aug 14, 2028

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B12/038

Abstract

A deep trench (DT) capacitor comprises a trench in a silicon layer, a buried plate surrounding the trench, a dielectric layer lining the trench, and a node conductor in the trench. The top surface of the poly node is higher than the surface of the silicon layer, so that it is high enough to ensure that a nitride liner used as a CMP etch stop for STI oxide surrounding a top portion of the poly node will be higher than the STI oxide, so that the nitride liner can be removed prior to forming a silicide contact on top of the poly node.