Crystallization Kinetics and Perpendicular Anisotropy of YIG Thin Films Grown on SiO ₂ /Si Substrates using Localized Laser Annealing

ABSTRACT Yttrium iron garnet (YIG) films have been widely studied for application in magnonic and integrated photonic devices. The growth of YIG thin films on SiO 2 /Si substrate, particularly films with perpendicular magnetic anisotropy (PMA), is important for compact magnonic and nonreciprocal photonic device applications. However, the crystallization kinetics of YIG films, especially their nucleation and growth kinetics, have rarely been explored. PMA is usually ensured by rare‐earth ion doping, which inevitably causes large Gilbert damping. In this paper, we report the crystallization kinetics and control of the magnetic anisotropy of YIG thin films grown on SiO 2 substrates via localized CO 2 laser annealing. The distinct nucleation and growth activation energies of YIG films (10.54 and 3.06 eV, respectively) enabled the separate control of these two steps, enabling the fabrication of YIG films with various grain sizes and distinct magnetic anisotropies. Clear PMA was observed in YIG films with a small grain size, which are dominated by the nucleation process. This study provides a theoretical basis for understanding the nucleation and growth kinetics of YIG films and offers a technical approach for controlling their magnetic anisotropy, contributing significantly toward YIG film research and paving the way for the development of high‐performance devices for magnonic and photonic applications.