MateriAlZ Seminar: Elizabeth Dickey
Friday, January 28, 2022 - 11 a.m. MST
Elizabeth Dickey
Distinguished Professor and Department Head of Materials Science & Engineering
Carnegie Mellon University
"Point Defect Engineering in Metal Oxides"
Zoom link | Passcode: 789234
MateriAlZ Seminar website | YouTube | Twitter
Abstract
Lattice defects play an important role in the dielectric and conductivity properties of electroceramic materials, and thus great effort is expended on controlling point defect concentrations via doping, oxygen activity and temperature control during processing. In device applications, because lattice defects are typically charged, applied electric fields provide a strong driving force for defect migration, and their spatiotemporal redistribution depends on numerous experimental variables including the interfacial boundary conditions. Ultimately the defect redistribution process leads to spatially varying conductivity profiles and often a concomitant macroscopic increase in leakage current in many dielectric materials. While this leakage current enhancement is detrimental in devices such as capacitors, the phenomenon can be utilized to form novel functional behaviors such as resistive switching in metal-oxides. This talk will review our current understanding and implications of point defect electromigration in important electroceramic materials. Recent efforts to effectively co-dope dielectric materials to improve their degradation resistance will be discussed.
Bio
Elizabeth Dickey is the Teddy & Wilton Hawkins Distinguished Professor and Department Head of Materials Science & Engineering at Carnegie Mellon University. Her research aims to develop processing-structure-property relationships for materials in which the macroscopic physical properties are governed by point defects, grain boundaries or internal interfaces. She received the Presidential Early Career Award for Scientists and Engineers (PECASE) for her work on metal-ceramic interfaces and was awarded the Fulrath Award by the American Ceramic Society in recognition of her research on the characterization of functional ceramics and composites. Professor Dickey is a fellow of the American Ceramic Society, the Microscopy Society of America and AAAS. She is currently an Editor of the Journal of the American Ceramic Society, Editor-In-Chief of Cambridge University Press’ Elements in Microscopy and Microanalysis and is currently the President of the American Ceramic Society.