Low Temperature (400°c) Ferroelectric Hf0.5Zr0.5O2 Capacitors for Next-Generation FRAM Applications

Abstract

In this study, ferroelectric properties of atomic layer deposited 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 films have been investigated for the development of future ferroelectric random access memory capacitors. A 10 nm thick HZO sample annealed at 400°C for 60 s in an N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> atmosphere after TiN top electrode deposition showed large switching polarization (~45 μC/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and low ferroelectric saturation voltage (~1.5 V) from pulse write/read measurement. Furthermore, fatigue measurements were performed and no significant degradation was observed until 108 switching cycles at 2 V.