Bipolar resistive switching behaviour in Mn$_{0.03}$Zn$_{0.97}$O/amorphous La$_{0.7}$Zn$_{0.3}$MnO$_3$ heterostructure films

摘要

Mn$_{0.03}$Zn$_{0.97}$O (MZO)/amorphous La$_{0.7}Zn$_{0.3}$MnO$_3$ (LZMO) heterostructures were deposited on p$^+$-Si substratesthrough sol–gel spin coating. Ag/MZO/LZMO/p$^+$-Si and Ag/LZMO/MZO/p$^+$-Si devices exhibit a bipolar, reversibleand remarkable resistive switching behaviour at room temperature. The ratio of the resistance at high-resistance state (HRS)to that at low-resistance state (LRS) ($R_{m HRS}/R_{m LRS}$) in the Ag/LZMO/MZO/p$^+$-Si device is approximately five orders of magnitude, and is maintained after over 10$^3$ successive switching cycles or over a period of $2imes 10^6$ s, indicating good endurance property and retention characteristics. Conversely, the ratio in the Ag/MZO/LZMO/p$^+$-Si device began to decrease after 100 successive switching cycles. The LZMO/MZO interface could play an important role in the resistive switching behaviour of the devices. The dominant conduction mechanism of the two devices is charge-trap emission.