Bipolar resistive switching in BiFe0.95Mn0.05O3 films

BiFe0.95Mn0.05O3 films were prepared on LaNiO3 buffered surface oxidized Si substrates by pulsed laser deposition. With silver glue dots prepared on the BiFe0.95Mn0.05O3 films, forming-free bipolar resistive switching (BRS) behavior has been observed in LaNiO3/BiFe0.95Mn0.05O3/Ag devices with the resistance ratio of the high resistance state (HRS) to the low resistance state (LRS) of about 3. With voltage of above 6.5 V applied on the top Ag electrode, a forming process with drastic increase of RHRS has been observed. The BRS behavior persists, and the RHRS/RLRS ratio is strongly enhanced to about 102. The conduction mechanisms of the LRS and HRS have been verified to be Ohmic and trap controlled space charge limited current (SCLC), respectively. The model based on the formation/rupture of the conducting filaments formed by O vacancies has been applied to explain the BRS behavior.