Impact of Thickness Control of Hf_0.5Zr_0.5O₂ Films for the Metal–Ferroelectric–Insulator–Semiconductor Capacitors

Abstract

Effects of controlling the film thickness of ferroelectric 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> (HZO) thin film were investigated to figure out the important design strategies for the metal- ferroelectric-insulator-semiconductor (MFIS) capacitors. Even though the maximum remnant polarization (2Pr) was obtained to be 23.4 μC/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> for the HZO capacitors with an HZO thickness of 20 nm, the ferroelectric memory window increased from 0.44 to 0.82 V with increasing the HZO thickness from 20 to 40 nm. The crystalline phases of the HZO thin films showed thickness-dependent variations with the relative dielectric permittivity.