Integration of Ferroelectric Al0.8Sc0.2N on Si (001) Substrate
Wenxin Sun, Jiuren Zhou, Ning Liu, Siying Zheng, Xiaoxi Li, Bochang Li, Yan Liu, Yue Hao, Genquan Han
Abstract
We evidently present the integration of ferroelectric Al <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{0}.{8}}$ </tex-math></inline-formula> Sc <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{0}.{2}}\text{N}$ </tex-math></inline-formula> onto a (001)-oriented silicon (Si) substrate. Our AlScN film, having a thickness of 116 nm, shows a remnant polarization ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${P}_{\text {r}}{)}$ </tex-math></inline-formula> exceeding <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$124.5~\mu \text{C}$ </tex-math></inline-formula> /cm2 and a coercive voltage of 71.9 V. Our ferroelectric Al <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{0}.{8}}$ </tex-math></inline-formula> Sc <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{{0}.{2}}\text{N}$ </tex-math></inline-formula> on Si demonstrates an endurance performance, surpassing <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1\times 10^{{4}}$ </tex-math></inline-formula> cycles under a stress of 75 V @ 100 kHz. The extrapolation of retention properties reveals that a substantial <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2{P}_{\text {r}}$ </tex-math></inline-formula> over <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$200~\mu \text{C}$ </tex-math></inline-formula> /cm2 can be guaranteed for a duration over <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{{8}}$ </tex-math></inline-formula> seconds at 300 K. Furthermore, the evaluation of the ratio of breakdown voltage to coercive voltage yields approximately 112% @ 300 K and 131% @ 500 K. These findings mark a critical advancement in the practical implementation of wurtzite ferroelectric field-effect transistor-structural memories and their high-density integration.