Spatial distribution of polarization and space charge in barium strontium titanate ceramics

Ferroelectric films of BaSrTiO3 (BST) are identified as a potential alternative to silicon dioxide in the silicon-based microelectronics industry owing to their very high dielectric constant. In this paper the distribution of space charge and polarization in BST ceramics is studied at room temperature with the laser induced pressure pulse method. Under voltage, dipoles orient rapidly but are subjected to the material nonuniformities. At longer time the ceramic becomes uniformly poled, indicating a transformation of the material. The remnant polarization remains uniform and stable for at least two days once the sample shorted. Long stress cycles and annealing have shown similar effects on the electrical behavior owing to similar microregion rearrangements.