Trapping Dynamics and Endurance in HfO2-FeFETs: An Insight from Charge Pumping

We investigate endurance degradation in hafnium oxide (HfO₂)-based ferroelectric field effect transistors (FeFETs) by analyzing interface (N_it) and near-interface oxide traps (N_ox) using a two-level charge pumping (CP) technique. After 10⁴ program (PG) / erase (ER) cycles at ±5 V, 100 ns, N_it increases by ~2×, and the memory window (MW) reduces from 1.2 V to 0.45 V. Temperature-dependent measurements reveal accelerated trap generation above 50 °C, with decreasing charge-pumping current (I_CP^max) due to deeper oxide trap occupation. Pulse parameter tuning shows that longer rise/fall times, and shorter hold durations mitigate N_it accumulation and delay memory window collapse. The extracted average interface trap density (D_it) reaches ~4×10¹² cm⁻²eV⁻¹ after cycling. These results emphasize the role of trap engineering in improving FeFET endurance for scaled non-volatile memory applications.