Resistance switching in oxide thin films

Resistance switching in transition metal oxide thin films has been observed in a variety of complex and binary oxides, and is the basis for development of non-volatile resistance random access memory (RRAM). We review here the electric-pulse induced resistance (EPIR) change effect, which is responsible for this switching and encompasses the reversible change of resistance of a thin oxide film under the application of short- and low-voltage pulses. Although the phenomenon has been observed in a number of oxide systems, there is still limited understanding of the origin of the resistance change. A recent model that has found fair acceptability incorporates oxygen ion/vacancy diffusion and pile-up near the interface region of the oxide at the impervious metal interface. Further efforts are still required to fine tune the model and apply it to the optimization of RRAM device development.