Variability Analysis for Ferroelectric Field-Effect Transistors
Gihun Choe, Shimeng Yu
Abstract
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 <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> Zr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> 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.