HfZrO-Based Ferroelectric Devices for Lower Power AI and Memory Applications

Si-friendly HfO 2-based ferroelectric devices have been strongly recognized as a novel technology booster for future integrated memory and logic systems. In this paper, we address our recent activities on TiN/Hf 0.5Zr 0.5O 2(HZO)/TiN MFM capacitors, HZO/Si FeFETs for memory applications and a newly-proposed reservoir computing using HZO/Si FeFETs and MFM capacitors for AI applications. We have demonstrated that MFM capacitors with HZO less than 5 nm can realize low crystallization temperature, excellent ferroelectricity, low operating voltage and high read/write endurance by performing sufficient wake-up operations to the thin HZO films. For the FeFET memory, we have found the importance of interfacial layers (ILs) between HZO and Si on the memory window. It has been revealed that the IL thickness is sensitive to the process temperature and that electron trapping around HZO/ILs has significant impacts on the memory operation. Finally, we have proposed and experimentally demonstrated reservoir computing using FeFETs for neuromorphic applications.