Title :
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
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;
Conference_Titel :
Applications of Ferroelectrics, 1998. ISAF 98. Proceedings of the Eleventh IEEE International Symposium on
Conference_Location :
Montreux
Print_ISBN :
0-7803-4959-8
DOI :
10.1109/ISAF.1998.786651
