Fabrication method for high-capacitance storage node structures

US5776660A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Mark C. Hakey · Saint Albans, US
• Steven J. Holmes · Colchester, US
• David V. Horak · South Burlington, US
• William H. Ma · Wappingers Falls, US

Key dates

• Filing date: Feb 3, 1997
• Grant date: Jul 7, 1998
• Expiry date: Feb 3, 2017

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/24628
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A high capacitance storage node structure is created in a substrate by patterning a hybrid resist (12) to produce both negative tone (16) and positive tone (18) areas in the exposed region (14). After removal of the positive tone areas (18), the substrate (12) is etched using the unexposed hybrid resist (12) and negative tone area (16) as a mask. This produces a trench (22) in the substrate (12) with a centrally located, upwardly projecting protrusion (24). The capacitor (26) is then created by coating the sidewalls of the trench (22) and protrusion (24) with dielectric (28) and filling the trench with conductive material (30) such as polysilicon.