Recent experimental advances in the ability to grow epitaxial ferroelectrics on semiconductors have provided an opportunity to study the intrinsic properties of these interfaces. It has been reported that a heterostructure of BaTiO3 grown on germanium has a commensurate crystalline oxide interface with a nonzero interface density of states. Including these states in a model of a ferroelectric oxide on a semiconductor substrate with a top metal electrode, we find that the oxide critical thickness necessary for stability of the ferroelectric state with polarization along the interface normal is substantially lowered by the contribution to the screening by the interface states. Materials parameters for BaTiO3 and Ge give a drop in estimated critical thickness from 39 nm to 7 nm.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics