Atomic-scale manipulation of potential barriers at SrTiO 3 grain boundaries

Abstract

In oxide grain boundaries (GBs), oxygen ions and their vacancies serve as a common denominator in controlling properties such as GB barrier height and capacitance. Therefore, it is critical to analyze, control and manipulate oxygen and vacancies at oxide interfaces as most of the practical devices are almost always influenced by the presence of electrostatic potential barriers at interfaces. Here, we report adjustment of a single GB potential barrier via manipulation of oxygen vacancy concentration using simple oxidation and reduction treatments. We validate our analysis with aberration-corrected HAADF imaging and column-by-column EELS coupled with macroscopic transport measurements of isolated GBs to gain important insight into the physical attributes of GB potential barriers. © 2005 American Institute of Physics.