Evolution of complementary resistive switching characteristics using IrO_x/GdO_x/Al_2O_3/TiN structure

摘要

The complementary resistive switching (CRS) characteristics using an IrO_x/GdO_x/Al_2O_3/TiN single cell are observed whereas the bipolar resistive switching (BRS) characteristics are observed for the IrO_x/GdO_x/TiN structure. Transmission electron microscope and energy dispersive X-ray spectroscopy depth profile show crystalline GdO_x film and the presence of higher amount of oxygen at both IrO_x/GdO_x interface and Al_2O_3 layer. Inserting thin Al_2O_3 layer, the BRS is changed to CRS. This CRS has hopping distance of 0.58 nm and Poole-Frenkel current conductions for the "0" and "1" states, respectively. A schematic model using oxygen vacancy filament formation/rupture at the TE/GdO_x interface and Al_2O_3 layer has been illustrated. This CRS device has good endurance of 1000 cycles with a pulse width of 1 μs, which is very useful for future crossbar architecture.