Ferroelectric based capacitor for use in memory systems and method for fabricating the same

US5679969A · kind A · utility

Assignee

• Radiant Technologies, Inc. · US

Inventors

• Joseph T. Evans, Jr. · Albuquerque, US
• Richard Womack · Albuquerque, US

Key dates

• Filing date: Jun 11, 1996
• Grant date: Oct 21, 1997
• Expiry date: Jun 11, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D1/696

Abstract

A ferroelectric based capacitor structure and method for making the same. The capacitor includes a bottom electrode having a layer of Pt in contact with a first layer of an ohmic material. The capacitor dielectric is constructed from a layer of lead zirconium titanate doped with an element having an oxidation state greater than +4. The top electrode of the capacitor is constructed from a second layer of ohmic material in contact with a layer of Pt. The preferred ohmic material is LSCO; although RuO.sub.2 may also be utilized. The capacitor is preferably constructed over the drain of an FET such that the bottom electrode of the capacitor is connected to the drain of the FET. The resulting capacitor structure has both low imprint and low fatigue.