Filament-Type Resistive Switching in Homogeneous Bi-Layer Pr[sub 0.7]Ca[sub 0.3]MnO[sub 3] Thin Film Memory Devices

Abstract

It is known that Pt/ Pr0.7 Ca0.3 Mn O3 (PCMO)/Pt structures show no hysteresis loops in current-voltage curves due to the symmetric top and bottom interfaces. Here, we prepared an asymmetric memory device using bi-layer PCMO thin films with different oxygen content. The repeatable and stable resistive switching is observed. The excellent resistive switching characteristics such as a large RHRS / RLRS (where HRS is the high resistance state and LRS is the low resistance state) ratio (∼1000), sweeping endurance (>100), and long retention time (> 105 s) can be obtained using a bipolar operation mode. It is suggested that the switching process can be elucidated to the formation and rupture of localized conductive filament along with the migration of oxygen ions.