講演情報
[11a-B21-3]Atomic Layer Engineering of Epitaxial Metal, Ferroelectric, and Antiferroelectric Materials for Advanced Devices
〇Miin-Jang Chen1, Yu-Sen Jiang1 (1.National Taiwan University)
キーワード：
Atomic layer deposition、Ferroelectric/Antiferroelectric Materials and Devices、Epitaxial Growth
Precise control over surface chemistry, crystallographic phase, and lattice orientation is critical for next-generation ferroelectric memory and antiferroelectric energy-storage devices. This presentation highlights our recent progress in atomic-layer-based thin-film engineering, including atomic layer epitaxy (ALE), hydrogen-manipulated ALE (HM-ALE), and atomic layer annealing (ALA), for the low-temperature fabrication of high-performance TiN, Hf0.5Zr0.5O2 (HZO), and ZrO2 heterostructures. HM-ALE enables epitaxial growth of TiN at a low deposition temperature of only 300°C, producing low-resistivity epitaxial electrodes that serve as effective templates for the epitaxial growth of overlying functional oxide layers. Upon TiN(111), ALE realizes the growth of polar-axis-oriented HZO films with strong ferroelectric polarization up to 79 μC/cm2 and distinct two-step 90° ferroelastic domain switching. ALA provides an alternative strategy to enhance HZO ferroelectricity, achieving wake-up-free behavior and a high remanent polarization of ~69 μC/cm2. For energy-storage applications, epitaxial ZrO2/TiN antiferroelectric heterostructures align the ZrO2 polar axis in the out-of-plane direction, enabling a high energy-storage density of approximately 118.6 J/cm3 and distinct time-resolved negative-capacitance behavior. In summary, atomic-layer engineering, including ALD, ALA, ALE, and HM-ALE, provides a powerful route for controlling low-temperature epitaxial growth, phase stabilization, polar-axis orientation, and polarization dynamics in functional oxides.