Investigation of factors affecting electrical properties of PZT thin film capacitors

Author

Kanai, Hideyuki ; Yamashita, Yohachi ; Yamakawa, Koji

Author_Institution

Labs. of Mater. & Devices Res., Toshiba Corp., Kawasaki, Japan

fYear

1998

fDate

1998

Firstpage

121

Lastpage

124

Abstract

Effects of morphology of Pt, orientation of PZT, and stoichiometry of PZT on electrical properties of PZT thin film capacitors prepared using the sol-gel technique were investigated. Although the predominant orientation of PZT grown on as-deposited Ti/Pt was (100), both heat-treatment of Ti/Pt bottom electrode and application of the Ti-seed technique to Ti/Pt bottom electrode promoted (111) orientation of PZT. However, the surface of PZT on heat-treated Ti/Pt was very rough in contrast to the smooth surface for Ti-seeded PZT. Remnant polarization P _r increased from 14 [μC/cm²] for (100) orientation of PZT formed on as-deposited Ti/Pt to 31 [μC/cm²] for heat-treatment and 44 [μC/cm²] for Ti-seed. However, fatigue properties did not improve even though surface morphology of Ti/Pt bottom electrode and orientation of PZT were changed. Electrical properties of PZT showed strong stoichiometry (A/B) dependence of PZT. In particular, excess PbO by 30 mole % (A/B=1.30) revealed great fatigue performance

Keywords

dielectric polarisation; ferroelectric capacitors; ferroelectric thin films; heat treatment; lead compounds; sol-gel processing; stoichiometry; surface topography; thin film capacitors; PZT; PbZrO3TiO3; Pt; Ti; Ti/Pt bottom electrode; fatigue; heat-treatment; morphology; orientation; remnant polarization; sol-gel technique; stoichiometry; surface roughness; thin film capacitors; Capacitors; Dielectric thin films; Electrodes; Fatigue; Pulse measurements; Random access memory; Rough surfaces; Surface morphology; Surface roughness; Transistors;

fLanguage

English

Publisher

ieee

Conference_Titel

Applications of Ferroelectrics, 1998. ISAF 98. Proceedings of the Eleventh IEEE International Symposium on

Conference_Location

Montreux

ISSN

1099-4734

Print_ISBN

0-7803-4959-8

Type

conf

DOI

10.1109/ISAF.1998.786651

Filename

786651