Fig. 5 (a) Area dependence of the read current. (b) Fitted I-V curves with SCLC conduction mechanisms.
Then, the underlying mechanism of the self-rectifying Pt/HZO/TiN device is investigated. Fig. 5a shows the area dependence of read currents in LRS and HRS, respectively. The read current for each device area were obtained from 20 switching cycles. As the device area increase from 9 µm2 to 2500 µm2, the read currents of both LRS and HRS increase approximately linearly, indicating an interface-type rather than localization-type resistive switching behavior. Fig. 5b shows the fitted I-V curves with SCLC conduction mechanism. A typical I-V characteristic plotted in a log-log curve for SCLC is bounded by the three limited curves, ohm’s law (I∝V ), traps filled limit current (I∝V2 ) and Child’s law. The result in Fig. 5b is consistent with the features of SCLC conduction mechanism.
Finally, a benchmark especially on rectify ratio, memory window, read power and endurance is provided in Table 1. Compared with previous self-rectifying devices, the proposed Pt/HZO/TiN devices in our work show competitive advantages, such as the largest memory window, lowest read power in HRS state.
Table 1. Performance benchmarking between our self-rectifying device and previous results.