Effects of RTA Rising Time on Ferroelectric Characteristics of HfZrO₂

Abstract

The ferroelectric (FE) properties of HfZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> were studied by modulating the rapid thermal annealing (RTA) rising time ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{r}$ </tex-math></inline-formula> ). As <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{r}$ </tex-math></inline-formula> becomes shorter, the polarization is clearly observed to increase prior to becoming saturated. On the contrary, the leakage current that is flowing through the FE film increases continuously. Our analysis of the FE properties of the material indicated that smaller grains are formed in the FE films after RTA with a shorter <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{r}$ </tex-math></inline-formula> , and that the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{r}$ </tex-math></inline-formula> -induced grain size determines the polarization switching and leakage current. Accordingly, our findings confirmed that both the polarization and leakage current can be simultaneously co-optimized using grain size engineering by modulating <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${T}_{r}$ </tex-math></inline-formula> .