Current saturation in In$_{2}$O$_{3}$-SrO ceramics: a role of oxidizing atmosphere

Abstract

Current-voltage dependence in In$_{2}$O$_{3}$-SrO ceramics contains a region where the current is increased weaker than the voltage. Such behavior is observed in oxygen atmosphere and is not registered in an inert one. Nonlinear current-voltage dependence is explained in terms of a relation between electronic processes at the grain boundaries and adsorption of oxygen in electric field. The role of adsorption processes is discussed on the basis of obtained data (current-voltage dependences, pore size distribution, secondary electron microscopy, and humidity sensitivity of conductance).