Direct measurement of triaxial strain fields around ferroelectric domains using X-ray microdiffraction

Ferroelectric materials, such as BaTiO3, have piezo electric properties that make them attractive for microelectronic and sensing applications. It is well known that the application of mechanical stress or electric field can alter the domain structure inferroelectrics. Indeed, the constitutive behavior of a ferroelectric is largely governed by the formation, movement and interact ion of its domains. Therefore, it is crucial that the micro mechanics of domains and their effect on internal stresses in ferroelectrics be understood. Here we show that the emerging technique of scanning X-ray micro diffraction can be used to measure directly, for the first time, the local triaxial strain fields around 90 degrees domains in single-crystal BaTiO3. Specifically, residuals train maps in a region surrounding an isolated, approximately 40 (micro)m wide, 90 degrees domain were obtained with 3 (micro)m resolution, revealing significant residual strains. This information is critical for accurate micromechanical modeling of domain behavior in ferroelectrics