Patent · US Expired

Thin film capacitor

US5978207A · kind A · utility

78Cited by
9References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1997
Grant dateNov 2, 1999
Priority date
Expiry dateOct 30, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D1/682
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Ferroelectric PbZr.sub.x T.sub.1-x O.sub.3 (PZT) thin films are deposited on Pt coated Si substrates by using RF magnetron sputtering. A method for obtaining desirable stoichiometric PZT, the desired ferroelectric perovskite phase, and better dielectric properties using a PZT target with Pb/(Zr+Ti) ratio of 1.2 and depositing at 350.degree. C., followed by thermal treatment at 620.degree. C. for 30 min is disclosed. The structural and electrical properties of the PZT layer were further improved by a method of fabricating a novel multi-layer structure which combined the PZT thin film with nanolayers of BaTiO.sub.3. The method and device of the present invention provided reduced leakage current density while maintaining high relative effective dielectric constants.

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