Patent · US Expired

Method for forming a multilayer electrode for a ferroelectric capacitor

US6746916B2 · kind B2 · utility

29Cited by
11References
51Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 4, 2002
Grant dateJun 8, 2004
Priority date
Expiry dateSep 4, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B12/033
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A ferroelectric or high dielectric constant capacitor having a multilayer lower electrode comprising at least two layers—a platinum layer and a platinum-rhodium layer—for use in a random access memory (RAM) cell is disclosed. The platinum layer of the lower electrode is formed such that it adjoins the capacitor dielectric, which is a ferroelectric or high dielectric constant dielectric such as BST, PZT, SBT or tantalum pentoxide. The platinum-rhodium layer serves as an oxidation barrier and may also act as an adhesion layer for preventing separation of the lower electrode from the substrate, thereby improving capacitor performance. The multilayer electrode may have titanium and/or titanium nitride layers under the platinum-rhodium layer for certain applications. The capacitor has an upper electrode which may be a conventional electrode or which may have a multilayer structure similar to that of the lower electrode.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.