Multilayer Metal-Oxide Memristive Device with Stabilized Resistive Switching

Variability of resistive switching is a key problem for application of memristive devices in emerging information-computing systems. Achieving a stable switching between the nonlinear resistive states is an important task on the way to implementation of large memristive cross-bar arrays and solving the related sneak-path-current problem. A promising approach is the fabrication of memristive structures with appropriate interfaces by combining the materials of electrodes with certain oxygen affinity and different dielectric layers. In the present work, such approach allows the demonstration of stabilized resistive switching in a multilayer device structure based on ZrO2(Y) and Ta2O5 films. It is established for the large-area devices that the switching is stabilized after several hundreds of cycles. A possible scenario of the stabilization is proposed taking into account experimental data on the presence of grain boundaries in ZrO2(Y) as the preferred sites for nucleation of filaments, self-organization of Ta nanocrystals as the electric field concentrators in Ta2O5 film, as well as oxygen exchange between oxide layers and interface with bottom TiN electrode. The robust resistive switching between nonlinear states is implemented in microscale cross-point devices without numerous cycling before stabilization promising for the fabrication of programmable memristive weights in passively integrated cross-bar arrays.