Stress-controlled scaling behavior of BaTiO3-based ferroelectrics

Abstract

The development of integration technology necessitates the miniaturization of ferroelectric devices and scaling down of materials thickness. Great value of scaling effect has presented in ferroelectric films, however, experimentally manipulated scaling effect remains ambiguous in bulk form. Here, we aim to demonstrate that the scaling effect in ferroelectric ceramics is highly sensitive to the specimen preparation, and show how it works via grinding process and site-dependent doping strategy. By taking barium titanate ceramics as an example, we find that the electro-strain of B-site substitution largely increases after halving the thickness and better strain stability with 50% increment is obtained, while A-site substitution hardly changes. The enhanced strain performance is identified as the stress-related increment of non-180° domains. This work gives insight for understanding and manipulating the scaling effect of bulk ferroelectric materials. More meaningful for normalized strain evaluation, our work demonstrates that clear indication of sample preparation should be given.