Ferroelectric diode-like resistive switching behavior in Bi0.95Er0.05FeO3/CuFe2O4 heterostructures for non-volatile memories

Non-volatile bipolar resistive random-access memory (RRAM) devices with the distinct heterostructures Bi0.95Er0.05FeO3/CuFe2O4 (BEFO/CFO) and Bi0.95Er0.05FeO3/CuFe2O4/Bi0.95Er0.05FeO3 (BEFO/CFO/BEFO) are fabricated by the sol-gel technique. The excellent resistive switching (RS) behavior is observed in both configurations. The ratio between the high resistance state (HRS) and low resistance state (LRS) of the BEFO/CFO heterostructure (102) exceeds that of the BEFO/CFO/BEFO heterostructure (10). The influences of the heterojunction interface on the RS characteristics underlying the RS mechanism are studied in detail. The conduction mechanism of the BEFO/CFO heterostructure predominantly arises from the space-charge-limited-conduction (SCLC) model, while the BEFO/CFO/BEFO heterostructure can be segmented into the SCLC model at the HRS and the Fowler-Nordheim (F-N) tunneling mechanism at the LRS. These results demonstrate that the RS characteristics can be tailored by manipulating the construction of heterojunction interfaces. Moreover, the I-V cycles, endurances and retention performance are also investigated.