Recent advances in hexagonal boron nitride based thermal interface materials: a minor review

The escalating power density and miniaturization of modern electronics have intensified the demand for efficient thermal management, positioning thermal interface materials (TIMs) as critical components in mitigating thermal contact resistance (TCR). Among various fillers, hexagonal boron nitride (h-BN) stands out due to its unique combination of high in-plane thermal conductivity and excellent electrical insulation. However, its highly anisotropic nature poses significant challenges for effective through-plane heat dissipation. This review comprehensively summarizes recent advances in h-BN-based TIMs, tracing the evolution from simple randomly blended composites to sophisticated structurally engineered systems. Special emphasis is placed on strategies such as surface modification, 3D network construction, and advanced alignment techniques—including magnetic induction, ice-templating, and the 90° flipping method—that enable vertical alignment of h-BN to harness its in-plane thermal conductivity for through-plane heat transfer. The review also highlights emerging insights into interfacial phonon bridging and surface engineering to minimize TCR. Finally, the review outlines current challenges and future research directions, emphasizing the need to co-optimize bulk thermal conductivity, mechanical compliance, and interfacial properties to meet the thermal management demands of next-generation electronics.