Oxygen transport in thin oxide films at high field strength

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Ionic transport in nanostructures under high electric field strengths has garnered attention due to its potential in advanced computer memory technologies. Moderate applied voltages create extreme electric fields in the MV/cm range over distances of a few nanometers, significantly affecting the activation energy for ionic jump processes. This results in an exponential increase in transport speed with voltage, contrasting with conventional high-temperature ionic conduction, which relies solely on thermal activation. In this research, the transport of small amounts of oxygen through a thin dielectric layer between conducting oxide electrodes was measured semiquantitatively by assessing conductance changes after applying a current. The relative conductance change, G/G, as a function of current I and duration t, follows an empirical law of the form G/G = CIAtB, with parameters C, A, and B ranging from 0 to 1. This law correlates with the predicted exponential increase in transport speed at high field strengths. The time-domain behavior is explained by a spectrum of relaxation processes akin to dielectric relaxation. Temperature significantly influences transport but is lower than anticipated, contradicting established high-field ionic transport laws. Epitaxial oxide layers, 5 to 70 nm thick, were created, and initial large-scale test samples were developed using shadow masks. A lithographic manufacturing process was also establish