Concurrent ionic migration and electronic effects at the memristive TiO x /La 1/3 Ca 2/3 MnO 3−x interface

W. ROMAN ACEVEDO; MARIA JOSE SANCHEZ; C. FERREYRA; C ACHA; R GAY; P. STOLIAR, F.Z-MARLASCA, D. RUBI ANDP. LEVY

JOURNAL OF PHYSICS - D (APPLIED PHYSICS)

IOP PUBLISHING LTD

Año: 2018 vol. 51

0022-3727

The development of reliable redox-based resistive random-access memory devices requiresunderstanding and disentangling concurrent effects present at memristive interfaces. We reporton the fabrication and electrical characterization of TiO x /La 1/3 Ca 2/3 MnO 3−x microstructuredinterfaces and on the modeling of their memristive behavior. We show that a careful tuningof the applied external electrical stimuli allows controlling the redox process between bothlayers, obtaining multilevel non-volatile resistance states. We simulate the oxygen vacanciesdynamics at the interface between both oxides, and successfully reproduce the experimentalelectrical behavior after the inclusion of an electronic effect, related to the presence of ann-p diode at the interface. The formation of the diode is due to the n- and p-character of TiO xand La 1/3 Ca 2/3 MnO 3−x , respectively. Our analysis indicates that oxygen vacancies migrationbetween both layers is triggered after the diode is polarized either in forward mode or inreverse mode above breakdown. Electrical measurements at different temperatures suggestthat the diode can be characterized as Zener-type. The advantages of our junctions for theirimplementation in RRAM devices are finally discussed.