Bipolar resistive switching in transition metal oxides based memory cells

Mechanism for bipolar resistive switching in transition metal oxides based memory cells

María José Sánchez
Centro Atómico Bariloche and Instituto Balseiro, CNEA, (8400) San Carlos de Bariloche, Argentina

DEI - Aula Beta, Ed. 24
6 luglio 2012
Ore 14.30

Abstract:

Motivated in its potential technological application in post-silicon electronic memory devices, the resistance switching effect in transition metal oxides is attracting a great deal of attention. This effect is a reversible and nonvolatile change in the resistance after the application of electrical (voltage or current) pulses. It has been observed in a plethora of systems, ranging from simple and complex oxides to organic compounds, though each one showing specific characteristics. Here, we focus on complex transition metal oxides (TMO) and introduce a model that qualitatively describes the migration of ionic defects (oxygen vacancies) at the nano-scale TMO-electrode interfaces. Our model shows that in those regions, that are highly resistive and often form Schottky barriers, strong electric fields develop, leading to a spatially inhomogeneous oxygen vacancies distribution and a concomitant resistive switching effect. Our numerical simulations under typical voltage protocols qualitatively reproduce key non-trivial resistance hysteresis experiments that we also report, thus providing valuable support to our model.

Contatti:
Daniele Ielmini

Area di ricerca:
Microelettronica e tecnologie emergenti