Variability Analysis for Ferroelectric Field-Effect Transistors

The random variation sources have a significant influence on the performance of ferroelectric field-effect transistors (FeFETs). We conducted a comparative analysis in TCAD on the process variation induced variability of the 28nm Hf
_0.5
Zr
_0.5
O
₂
based FeFETs. The ferroelectric/dielectric phase variation in the HZO gate stack, the metal work function variation and the gate line-edge roughness effects are incorporated to quantify their impacts on the threshold voltage and memory window variation. The phase variation, modeled in a Voronoi diagram, agrees with the measured distribution in HZO thin film, which is found to be one of the critical factors in FeFETs memory window variation.