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 ( $\text{N}_{\text {IL/OS}}$ ) increases, the memory window (MW) exhibits significant fluctuation with a larger $\sigma _{\text {MW}}$ , resulting in the degradation of $\mu _{\text {MW}}$ ; 2) MW is impacted by the density of FE/IL interface traps ( $\text{N}_{\text {FE/IL}}$ ) by modifying the electric field in FE and IL layers, consequently leading to a substantial $\mu _{\text {MW}}$ but no obvious change in $\sigma _{\text {MW}}$ ; 3) when considering the combined impact of both types of traps, the impact of FE/IL interface traps on increasing $\mu _{\text {MW}}$ is suppressed with an increased $\text{N}_{\text {IL/OS}}$ . However, it is crucial to note that although the larger $\text{N}_{\text {IL/OS}}$ dominates the overall MW fluctuation, the fluctuation caused by $\text{N}_{\text {FE/IL}}$ cannot be disregarded especially with smaller $\text{N}_{\text {IL/OS}}$ . These findings provide valuable insights into the understanding of interface trap effects on the device variation of OS-FeFET memories.