Exploring Effective Thermal Conductivity and Thermal Resistance of Conductive Film Adhesive Bondline for High Power Density Applications

Silver filled epoxy film adhesives are widely used in electronic device assembly due to its dual functions in bonding different parts and facilitating heat transfer in electronic devices. The thermal properties of a film adhesive product are often provided in a form of intrinsic bulk thermal conductivity. However, when assessing the thermal performance of a conductive adhesive within a bonded assembly, the observed value might not be equivalent to the bulk property of a free-standing cured sample. In this paper, we use “sandwich” method enabled by laser flash to investigate the effective thermal resistance of a newly developed conductive film adhesive in an assembly that simulates the electronic device packaging. The assembly was prepared under different processing conditions such as bondline thicknesses and bonding pressures. The effects of bonding conditions and adherends on the thermal performance of this material will be discussed. This provides people with valuable insights on device packaging, material selection and design validation.