In situ electric field-assisted curing enables low dielectric constant and loss through polarization suppression

Low-dielectric materials are crucial for reducing RC delay in high-density integrated circuits. Here, we report an electric field-assisted in situ curing strategy for dicyclopentadiene-based epoxy films to achieve reduced dielectric constant (εr) and loss tangent (tan δ). The applied electric field modulates local chain conformations and promotes crystalline microdomain formation, effectively suppressing dipolar polarization. Under an electric field of 6 kV mm−1, εr and tan δ are reduced by up to 8.5% and 78.9% at 102 Hz, and by 7.8% and 7.1% at 5 GHz, respectively. This work provides a unique route for tuning dielectric properties via electric field-induced structural control, offering potential for advanced electronic packaging applications.