Performance Improvement of Hf0.5Zr0.5O2-Based Ferroelectric-Field-Effect Transistors With ZrO2 Seed Layers

Hf 0.5 Zr 0.5 O 2 (HZO)-based ferroelectric-field-effect transistor (FeFET) with a ZrO 2 seed layer was demonstrated. It was found that the ZrO 2 seed layer could effectively improve the ferroelectric properties of the (hafnium zirconium oxide) HZO thin film. The remanent polarization and the coercive voltage of the metal-ferroelectric-insulator-semiconductor (MFIS) structure with the ZrO 2 seed layer were larger than those without the seed layer. Moreover, the FeFET with the ZrO 2 seed layer showed wider counterclockwise hysteresis loops in the transfer characteristics than that without the seed layer, achieving a large memory window of about 2.8 V. These results validate the advantages of the ZrO 2 seed layer in promotion of FeFET performance and thus warrant further study.