Hideaki Tanimura, Tomoya Mifune, Yuma Ueno, Hironori Fujisawa, Seiji Nakashima, Ai I. Osaka, Shinichi Kato, Takumi Mikawa
Japanese Journal of Applied Physics, 64(1) 01SP05-01SP05, Jan 1, 2025 Peer-reviewed
Abstract
Superior ferroelectric properties of Al-doped HfO2 (HAO) thin films are demonstrated using flash lamp annealing (FLA). This annealing approach is a low-thermal-budget treatment that features short annealing times at the millisecond timescale. We first clarified the annealing conditions with respect to optimum ferroelectricity. The results show that 5-millisecond annealing at 1000 °C is sufficient for adequate crystallization, achieving a high 2Pr value of 17.3 μC cm−2. By adjusting the cooling rate on the millisecond timescale during crystallization annealing, a high cooling rate of 182 °C ms−1 exhibited a superior 2Pr value of 16.6 μC cm−2, in contrast to a slow cooling rate of 12 °C ms−1, which yielded a 2Pr value of 10.2 μC cm−2. The results indicate that the control of the cooling rate is crucial for achieving an optimum 2Pr value, illustrating the potential of FLA for forming high-quality ferroelectric thin films.