Interface-type resistive switching in perovskite materials

Abstract

Resistive switching (RS) is currently one of the hot topics in the frontier between materials science and microelectronics, crosslinking both research communities. Among the different types of RS phenomena that have been reported, this review focuses particularly on interface-type RS, for which the change in resistance is related to a modification in the materials properties occurring at the interface over the entire electrode area. In particular we have summarized the most interesting reports on perovskite oxides, a versatile oxide crystal structure which presents a plethora of functional properties depending on its exact composition and structural symmetry. We present the most relevant mechanisms inducing RS, such as valence change, due to a combination of oxygen vacancy drift and redox reactions; electronic correlations; and ferroelectricity. For each case we explain the physico-chemical processes triggered by the application of an external voltage (or current), which ultimately lead to a change in resistance at the interface between the metal electrode and the oxide. Special attention is paid to the material aspects of interface-type switching, and in particular to how the RS characteristics can be improved or triggered by cation doping and oxygen off-stoichiometry, by the introduction of additional layers and by changing the nature of the electrodes. Recent progress in memristive devices based on perovskites is also reported and the figures of merit reached are compared to those obtained for state-of-the-art filamentary type RS binary oxides.