Resistance Switching and Carrier Transport Mechanisms of HfO2-Based Ferroelectric Diode

We have experimentally studied resistance switching and carrier transport mechanisms of HfO2-based ferroelectric diode (FD) by systematic measurement as well as current fitting with possible carrier transport models. FD with TiN/HZO/Al2O3/IGZO structure is fabricated with a low thermal budget of 400 °C and exhibits robust memory and self-rectifying characteristics. Fitting results show that current in high-resistance state (HRS) follows thermionic emission (TE), while low-resistance state (LRS) is dominated by Poole–Frenkel (PF) emission. The switching between HRS and LRS is attributed to ferroelectric polarization switching combined with sufficient electron trapping. This work provides fundamental understanding of device physics of HfO2-based FD for high-density and low-power memory applications.