Synthesis of Spherical Hexagonal Boron Nitride via Precursor Morphology Control

The growing demand for high‐performance semiconductors, driven by the advancement of emerging industries such as artificial intelligence (AI), necessitates the development of novel materials for thermal management. In this respect, hexagonal boron nitride (h‐BN) has emerged as a promising candidate due to its unique properties. However, challenges arise from its two‐dimensional layered structure, resulting in thermal transfer anisotropy and poor fluidity when mixed with polymers for thermal management. To address these challenges, researchers have attempted to fabricate h‐BN into spherical shapes. In this study, a two‐step synthesis method of spherical h‐BN (s‐BN) particles via control of the precursor morphology and a subsequent thermal reaction is proposed. Therefore, as‐fabricated s‐BN exhibits solid spherical shapes with a uniform size distribution, with a median particle size of 0.955 μm. These s‐BN particles, when integrated into epoxy resin, disperse homogeneously, forming efficient heat transfer networks that achieve a 138% improvement in thermal conductivity compared to h‐BN particles with similar diameters, even at lower viscosities. This can overcome the limitations found in the conventional particle shapes while preserving the advantages of h‐BN. Furthermore, it is anticipated that the s‐BN will be applied in thermal management systems, thereby accelerating advancements in electronic technology.