Computational investigations into the operating window for memristive devices based on homogeneous ionic motion

A model that describes the homogeneous migration of oxygen vacancies as a function of electric field, temperature, and activation energy of diffusion was used to investigate the resistance switching and retention characteristics of memristive SrTiO 3 Schottky devices. Numerical simulations suggest that, though ionic motion results in switching, it is not possible to meet the criteria of fast switching and long retention simultaneously; conditions that lead to sufficiently fast switching also lead to unacceptably fast decays of programmed states. However, an operational window is found when a term accounting for local enhancement of electric field in the dielectric is included. A discussion of the appropriateness of this inclusion is provided.