Dresden 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DS: Dünne Schichten

DS 19: Thin film deposition and process characterization I

DS 19.2: Vortrag

Donnerstag, 30. März 2006, 11:45–12:00, GER 38

Ba substituted Pb(Zr_xTi_1−x)O₃ Thin Films grown by MOCVD — •Jochen Puchalla, Susanne Hoffmann-Eifert, and Rainer Waser — IFF/IEM and CNI, FZ Jülich, Jülich, Germany

The most prominent ferroelectric material for integrated non-volatile memories is Pb(Zr,Ti)O₃. In this study we report on the modification of PZT thin films by substitution of Pb against Ba in order to study the effects accompanied with incorporation of a bigger A-site cation in the PZT system. The polycrystalline (Pb,Ba)(Ti,Zr)O₃ films are grown on Ir(111)/TiO₂/SiO₂/Si as well as on Pt(111)/TiO₂/SiO₂/Si substrates at temperatures between 580^oC and 650^oC applying a liquid-delivery MOCVD technique. A PZT (30/70) film of 150 nm thickness shows good ferroelectric properties with P_r = 35 µC/cm² and E_c = 90 kV/cm. In first randomly oriented films the Ba substitution was unfortunately not effective in lowering the coercive field. The (Pb,Ba)(Ti,Zr)O₃ films show improved phase stability and a more homogeneous morphology compared to the pure PZT films. In addition the dielectric losses in the PBZT films are as small as 0.025. The presentation will in addition deal with the Ba substitution effect in films with a preferred orientation of the grains, namely (111). Further studies address the formation of IrO₂ or PbPt_x interfacial layers, and the analysis of the ferroelectric and dielectric properties and the leakage currents in the Ba-doped PZT thin films.