|About this Abstract
||Materials Science & Technology 2012
||Advances in Dielectric Materials and Electronic Devices
||Enhanced Capacitive Energy Density Via Reduced Field Tuning
||Harlan J. Brown-Shaklee, David I. Shahin, Kelsey E. Meyer, Ryan P. Wilkerson, Michael J. Campion, Geoff L. Brennecka
|On-Site Speaker (Planned)
||Geoff L. Brennecka
Use of high-permittivity ceramics for capacitive energy storage is plagued by the reduction in permittivity with increased applied electric field, a phenomenon known as voltage tuning. We present here our recent work on efforts to design in minimal tuning in the family of Bi-modified BaTiO<SUB>3</SUB>-based weakly-coupled relaxor dielectrics through careful control of cation distribution and microstructure development while reducing sintering temperatures for compatibility with economical cofired electrodes. With appropriate processing, dense ceramics have been formed which maintain permittivity values >1500 at fields in excess of 100kV/cm and voltages exceeding 10kV; integrated solution-derived thin films of these materials also maintain permittivity values >1000 under fields >1MV/cm. Both bulk ceramics and thin films maintain high permittivity and nearly-linear voltage response across broad temperature ranges. MLCCs of these materials provide energy densities approaching those of tantalum electrolytic capacitors but with dramatically lower ESR and significantly greater temperature stability.