Electrode dependence and film resistivity effect in the electric-field-induced resistance-switching phenomena in epitaxial NiO films

We have investigated the electric-field-induced resistance-switching phenomena using Al and Ni electrodes on epitaxial NiO films with various resistivities. For excluding effects due to grain boundaries and roughness of NiO–electrode interfaces, epitaxial NiO films having atomically flat surfaces and high crystalline quality were fabricated by pulsed laser deposition. It is suggested that the resistance switching occurs around Al–NiO interfaces since only the electrode pairs including Al exhibit the resistance switching. Furthermore, this resistance switching strongly depends on NiO film resistivities, indicating that carrier density is also an important factor for resistance switching.