Multi-mode resistive switching behaviors induced by modifying Ti interlayer thickness and operation scheme

To overcome the practical issues existed in RRAMs application, complementary resistive switching (CRS) and self-compliance effect are investigated to alleviate sneak current issue and avoid external compliance current (I-comp), respectively. It is remarkable that the two resistive switching (RS) behaviors are attempted to achieve in the same system of Pt/HfO2(7.5-x)/Ti(2x)/HfO2(7.5-x)/Pt (x = 0, 2.5, 3.5 nm) device fabricated by magnetron sputtering, i.e., multi-mode resistive switching behaviors are modulated by varying Ti interlayer thickness and operation scheme, such as initial I-comp and applied voltage during reset switching. As indicated by the results, typical bipolar resistive switching (BRS) and CRS behaviors exhibit in Pt/HfO2(similar to 4 nm)/Ti(similar to 7 nm)/HfO2(similar to 4 nm)/Pt devices, and self-compliance effect appears in Pt/HfO2(similar to 5 nm)/Ti(similar to 5 nm)/HfO2(similar to 5 nm)/Pt devices. After investigated the conductive mechanisms, it is proposed adopting conceivable switching mechanism associated with the formation of oxygen vacancy (V-o) and metallic conduction filament (CF) to understand CRS and self-compliance effect. The exploration of multi-mode RS behaviors paves the way to improve the flexibility and convenience of RRAMs in actual application. (c) 2016 Elsevier B.V. All rights reserved.