About this Abstract |
Meeting |
Materials Science & Technology 2020
|
Symposium
|
Functional Defects in Electroceramic Materials
|
Presentation Title |
Co-doping Strategies for Controlling Electrical Conductivity of BaTiO3 Ceramics |
Author(s) |
Elizabeth Dickey, Gyung Hyun Ryu, Preston Bowes, Jonathon Baker, Douglas Irving |
On-Site Speaker (Planned) |
Elizabeth Dickey |
Abstract Scope |
The degradation kinetics of important dielectric materials, such as BaTiO3, are highly influenced by the time-dependent electromigration of intrinsic lattice defects. The spatial redistribution of point defects also deteriorates ferroelectric properties by forming an internal bias field, leading to asymmetric polarization and strain hysteresis loops. Therefore, controlling point defect concentrations and mobilities is necessary to improve not only the initial material conductivity, but also the device lifetime and breakdown strength. This presentation will discuss co-doping design strategies to control defect concentrations and hence conductivity in BaTiO3. Experimental conductivity measurements are interpreted in the context of density functional theory (DFT)-based grand canonical point defect simulations. These studies provide fundamental insight into the ability of certain co-dopants to pin the Fermi level over broad oxygen activity ranges and improve the semi-insulating properties and degradation properties of BaTiO3. This research is sponsored by AFOSR under grant no. FA9550-19-1-0222. |