The Role of Interfaces in Performance, Degradation, and Breakdown of Non-Linear Dielectrics Under Extreme Conditions
Abstract
The proposed research program focused on providing a fundamental, mechanistic understanding of interface-mediated polarization, conduction, degradation, and breakdown processes in non-linear dielectric materials. The research focused on model systems representing prototypical high permittivity dielectrics, for which there are well-established understandings of basic material properties, and which are amenable to both atomistic-scale and mesoscale modeling. Three main types of interfaces that impact the pre-breakdown and breakdown processes were studied, including electrode-dielectric interfaces, dielectric grain boundaries, and domain wall interfaces. We investigated a coupling between different time-scale transport phenomena, which collectively limit electrical performance in extreme environments. New techniques were developed, new insights into the coupling of bulk and interfacial phenomena addressed transient changes in the degradation prior to breakdown. The research team developed unique experimental methods to interrogate electronic, thermal, and ionic transport processes over a range of relevant spatial and temporal scales. These data were utilized to develop phenomenological models of interface-mediated degradation and breakdown processes, which, in turn, were used to guide and validate theoretical models developed by collaborative research teams. From this knowledge, we understand that the background impurity doping had to be overridden with strategic co-doping to balance out mobilities of both ionic vacancy migration and also pin the Fermi level of the dielectric.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 10, 2019
- Accession Number
- AD1085975
Entities
People
- Clive A. Randall
Organizations
- Pennsylvania State University