Impact of Random Interface Traps Fluctuation on Device Variation of Oxide-Semiconductor Ferroelectric Field-Effect Transistor Memories

In this letter, we systematically investigate the impact of randomly distributed ferroelectric/interlayer (FE/IL) and interlayer/oxide-semiconductor (IL/OS) interface traps, both individually and in combination, on the variability of oxide-semiconductor ferroelectric field-effect transistor (OS-FeFET) memory devices. Our study demonstrates that: 1) as the density of IL/OS interface traps (N-IL/OS) increases, the memory window (MW) exhibits significant fluctuation with a larger sigma(MW), resulting in the degradation of mu MW; 2) MW is impacted by the density of FE/IL interface traps (N-FE/IL) by modifying the electric field in FE and IL layers, consequently leading to a substantial mu MW but no obvious change in sigma(MW); 3) when considering the combined impact of both types of traps, the impact of FE/IL interface traps on increasing mu MW is suppressed with an increased N-IL/OS. However, it is crucial to note that although the larger N-IL/OS dominates the overall MW fluctuation, the fluctuation caused by NFE/IL cannot be disregarded especially with smaller N-IL/OS. These findings provide valuable insights into the understanding of interface trap effects on the device variation of OS-FeFET memories.