Thickness Effects on Physical and Ferroelectric Properties of Bi3.35La0.85Ti3O12 (BLT) Films with $c$-axis-Preferred and Random Orientations

概要

論文の詳細を見る
Thickness effects on dependences of physical and ferroelectric properties were investigated for two kinds of Bi3.35La0.85Ti3O12 (BLT) film with $c$-axis-preferred and random orientations. BLT films were prepared on Pt/TiOx/SiO2/Si substrates by the metalorganic decomposition (MOD) method, and their crystalline orientation was controlled by baking and rapid thermal annealing (RTA) conditions. When scaling down thickness from 210 to 70 nm, the $c$-axis-oriented film showed a big reduction in switching polarization (P*-P∧) from 13 to 6 μC/cm2 due to the predominant negative effect of the increased degree in $c$-axis-preferred orientation rather than the positive effect of increased grain size. However, the randomly oriented film showed no physical change such that it maintained a large polarization of 15–16 μC/cm2 in spite of the thickness reduction. Coercive field (2$E_{\text{c}}$) and fatigue-free property showed no significant thickness dependence for both BLT films.
INSTITUTE OF PURE AND APPLIED PHYSICSの論文
2003-02-15