HfO₂-ZrO₂Superlattice Ferroelectric Field-Effect Transistor With Improved Endurance and Fatigue Recovery Performance

In this brief, we report that HfO2-ZrO2 superlattice (SL) ferroelectric field-effect transistors (FeFETs) demonstrate improved endurance, fatigue recovery, and retention performance compared to the HfZrOx (HZO) control devices. During the program/erase (P/E) cycling and data retention, the density of interface traps is observed to increase less in the SL FeFETs than in the HZO transistors. This is due to the larger effective equivalent oxide thickness (EOT) of the SL, which reduces the electric field dropped at the SiO2 interfacial layer (IL) in the SL transistor during P/E operations, thereby weakening the generation of interface traps and mitigating memory window (MW) degradation in SL devices. After undergoing 1010 P/E cycles, the SL FeFET still achieved an MW above 500 mV with fatigue recovery.