Characterizing Ferroelectric Properties of Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub> From Deep-Cryogenic Temperature (4 K) to 400 K
Jae Hur, Yuan-Chun Luo, Zheng Wang, Sarah Lombardo, Asif Islam Khan, Shimeng Yu
Abstract
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 has obtained considerable attention for emerging non-volatile memory (eNVM) and synaptic device applications. To our best knowledge, the polarization switching of HZO has not been comprehensively investigated in wide-ranging temperatures from deep-cryogenic 4 K to elevated temperature 400 K within the same set of test structures. In this work, we experimentally characterize the reliability effects such as endurance (wake-up, fatigue, and breakdown), retention (including imprint), and small-signal response of the HZO capacitor from the lowest temperature reported (4 K) to the elevated temperature (400 K). We demonstrate one of the highest endurance cycles <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$ > 3.5\times 10^{10}$ </tex-math></inline-formula> among reported TiN/HZO/TiN capacitors with negligible wake-up/fatigue effects or retention degradation, all obtained at 4 K. Based on the experimental results, we further simulated ferroelectric random access memory (FeRAM) and ferroelectric field-effect transistor (FeFET) to evaluate their potentials as cryogenic memories.