Improved resistive switching properties in Ti/TiOx/La0.7Ca0.3MnO3/Pt stacked structures

A TiOx layer (∼20nm) was designed and introduced by a pulse laser deposition method to simulate the TiOx layer that developed naturally when the Ti top electrode was deposited on a La0.7Ca0.3MnO3 (LCMO) film. Comparing Ti/LCMO/Pt structures with those of Ti/TiOx/LCMO/Pt, we found that the inserted TiOx layer between the Ti top electrode and the LCMO film improves the resistive switching (RS) properties. The Ti/TiOx/LCMO/Pt structure shows a large junction resistance (∼32kΩ), large RHRS/RLRS ratio (∼10), and good endurance (>80 cycles). This improvement of RS properties may be mainly attributed to the modification of the n-p junction barrier width at the TiOx/LCMO interface due to the oxidation/reduction of an interfacial TiOx layer adjacent to the LCMO layer. In addition, the results of pulse measurements also show an improvement of RS properties in Ti/TiOx/LCMO/Pt structures.