Magnetic Field-Directed Alignment of MOF-Derived Superparamagnetic Fillers for Thermal Management in Epoxy Molding Compounds

This study presents a magnetic field-directed strategy for constructing thermal network in epoxy molding compounds (EMCs) using metal–organic framework (MOF)-derived superparamagnetic fillers (MSFs). ZIF-67, composed of cobalt ions and organic ligands, is carbonized to produce cobalt-containing carbonaceous MSFs, in which the superparamagnetic behavior is confirmed by VSM analysis. A one-dimensional (1D) alignment of MSFs in the EMC matrix is induced by an external magnetic field during the B-stage pre-curing process. Subsequently, the magnetic field is removed to fix the aligned network in the C-stage curing process. The aligned structure is retained after curing owing to the negligible remanent magnetization of the superparamagnetic fillers. Cross-sectional SEM analysis confirms the formation of continuous and directional heat-conduction pathways within the EMC. Infrared thermography analysis demonstrates enhanced heat dissipation performance of the MSF-added EMC compared to that of pristine EMC. The magnetically aligned EMC exhibits faster heat spreading and lower local temperature accumulation due the continuous 1D MSF network providing an efficient pathway for directional thermal transport. Consequently, this study proposes a novel filler alignment strategy for high-performance thermal management in next-generation EMC materials. By combining MOF-derived superparamagnetic fillers with magnetic field-assisted assembly, continuous thermal pathways can be effectively constructed within EMC system, providing a promising strategy for advanced electronic devices and semiconductor packaging applications.
- This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. RS-2025-02303250), and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. RS-2025-25396489).