Scientific and engineering issues of the state-of-the-art and future multilayer capacitors

BaTiO₃-based multilayer capacitors are rich with the science of crystal chemistry, defect chemistry, phase transition theory, ferroelectricity, and processing. State-of-the-art multilayer capacitors are fabricated with base metals, submicron grains and have thickness of layers approaching one micron. There are, however, needs to keep improving the volumetric efficiency of capacitance, improve reliability in thin layers, and increase the number of active layers. This paper summarizes and reviews some of the studies our group is performing to scientifically aid progress in this fast moving field. Specifically, we will review size effect issues, the role of rare-earth doping in improving degradation resistance, and the potential of electrophoretic deposition to produce multilayer structures with nanopowders.