A novel phase change film with high thermal conductivity and excellent electromagnetic shielding properties by combining Field's metal with tungsten

The rapid advancement of high-frequency and integrated electronic devices necessitates the development of thermal interface materials (TIMs) that possess electromagnetic interference (EMI) shielding properties to ensure system reliability. Polymer packaging of low-melting metals, which possess excellent thermal and electrical properties, limits their thermal conductivity (TC) and EMI shielding effectiveness (SE). Herein, a novel high-performance phase change TIM based on Field's metal (FM) is developed by incorporating tungsten (W) particles to enhance its various properties for the first time. Based on the excellent wetting properties of FM and its metal oxides on the W surface, they can form stable composite materials. In addition, the incorporation of W significantly influences the rheological properties of the molten composites, leading to increased yield strength and viscosity, which enhances the anti-leakage effects. The melting point of the prepared phase change film is approximately 60 °C. After the phase change, the film transitions into a molten state, which leads to a reduction in interface thermal resistance. The composite film, fabricated from the optimal composite material, exhibits a TC value of 30.74 W m −1 K −1 , while the EMI SE reached an impressive 111.2 dB at a thickness of just 200 μm. The film developed in this work achieves an ideal balance between heat dissipation and EMI shielding, and its overall performance significantly exceeds that of TIMs reported in previous literature. This work sheds light on developing TIMs with excellent heat dissipation performance and EMI shielding properties.