Grain Engineering Of High Energy Density Batio3 Thick Films Integrated On Si

Ferroelectric (FE) ceramics with a large relative dielectric permittivity and a high dielectric strength have the potential to store or supply electricity of very high energy and power densities, which is desirable in many modern electronic and electrical systems. For a given FE material, such as the commonly-used BaTiO3, a close interplay between defect chemistry, misfit strain, and grain characteristics must be carefully manipulated for engineering its film capacitors. In this work, the effects of grain orientation and morphology on the energy storage properties of BaTiO3 thick films were systematically investigated. These films were all deposited on Si at 500 °C in an oxygen-rich atmosphere, and their thicknesses varied between ~500 nm and ~2.6 μm. While a columnar nanograined BaTiO3 film with a (001) texture showed a higher recyclable energy density Wrec (81.0 J/cm3vs. 57.1 J/[email protected] MV/cm, ~40% increase) than that of a randomly-oriented BaTiO3 film of about the same thickness (~500 nm), the latter showed an improved energy density at a reduced electric field with an increasing film thickness. Specifically, for the 1.3 μm and 2.6 μm thick polycrystalline films, their energy storage densities Wrec reached 46.6 J/cm3 and 48.8 J/cm3 at an applied electric field of 2.31 MV/cm (300 V on 1.3 μm film) and 1.77 MV/cm (460 V on 2.6 μm film), respectively. This ramp-up in energy density can be attributed to increased polarizability with a growing grain size in thicker polycrystalline films and is desirable in high pulse power applications.

Nanostructures in Ferroelectric Films for Energy Applications: Grains, Domains, Interfaces and Engineering Methods presents methods of engineering nanostructures in ferroelectric films to improve their performance in energy harvesting and conversion and storage. Ferroelectric films, which have broad applications, including the emerging energy technology, usually consist of nanoscale inhomogeneities. For polycrystalline films, the size and distribution of nano-grains determines the macroscopic properties, especially the field-induced polarization response. For epitaxial films, the energy of internal long-range electric and elastic fields during their growth are minimized by formation of self-assembled nano-domains. This book is an accessible reference for both instructors in academia and R&D professionals. Provides the necessary components for the systematic study of the structure-property relationship in ferroelectric thin film materials using case studies in energy applications Written by leading experts in the research areas of piezoelectrics, electrocalorics, ferroelectric dielectrics (especially in capacitive energy storage), ferroelectric domains, and ferroelectric-Si technology Includes a well balanced mix of theoretical design and simulation, materials processing and integration, and dedicated characterization methods of the involved nanostructures

Ferroelectric materials have been and still are widely used in many applications, that have moved from sonar towards breakthrough technologies such as memories or optical devices. This book is a part of a four volume collection (covering material aspects, physical effects, characterization and modeling, and applications) and focuses on ways to obtain high-quality materials exhibiting large ferroelectric activity. The book covers the aspect of material synthesis and growth, doping and composites, lead-free devices, and thin film synthesis. The aim of this book is to provide an up-to-date review of recent scientific findings and recent advances in the field of ferroelectric materials, allowing a deep understanding of the material aspects of ferroelectricity.