Co doping Perovskite Dielectrics for Higher Reliability under Extreme Voltage and Temperature Conditions
Abstract
The program builds upon a recent AFOSR supported program that studied the electric field driven spatio temporal redistribution of lattice defects in oxide perovskites and the consequences for the local and global conductivities and consequent instigation of thermal breakdown. The proposed strategy to improve dielectric reliability is to co dope the perovskite materials with transition metal and rare earth cations to overcome the background trace impurities that are a consequence of the purification limits of metal oxide materials used in capacitor manufacturing. We also aim to identify codopants that tend to form complexes with oxygen vacancies, thus lowering their mobility in the lattice, which would slow the degradation process. The program involve synthesizing doped SrTiO3 and BaTiO3 ceramics and measuring the high temperature and low temperature conductivities as a function of oxygen partial pressure, which provides indirect information about the defect chemistry of the materials. In addition, we will probe the structural modifications to the perovskite lattice using x ray scattering and absorption techniques in collaborations with NIST collaborators. These experimentally measured properties will be compared to those predicted from first principles calculations (from another AFOSR funded program). The feedback loop between computationally derived defect chemistry and experimental measurements of defect chemistry will further the development of predictive design tools for controlling the conductivity and degradation behavior of dielectric materials.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- FA95501910222
Entities
People
- Douglas L Irving
Organizations
- Air Force Office of Scientific Research
- North Carolina State University
- United States Air Force