Electrical Conduction in Ferromagnetic Metal Oxide Junctions

The electrical conduction from 4.2°K to room temperature in thin film Ni–NiOx-metal junctions was studied. Tunneling is the dominant conduction mechanism at low temperature; at high temperature, Schottky thermionic emission dominates. The effective barrier thickness determines at what temperature the conductivity changes from tunneling to Schottky emission. Atomic penetration into the oxide is important, and there appear to be broad transition regions at the metal-oxide interfaces. Using the conventional models, the barrier heights are approximately 0.2 eV.