A carbon fiber solder matrix composite for thermal management of microelectronic devices

Abstract

A carbon fiber based tin–silver–copper alloy matrix composite (CF-TIM) was developed via electrospinning of a mesophase pitch with polyimide and carbonization at 1000 °C, followed by sputter coating with titanium and gold, and alloy infiltration. The carbonized fibers, in film form, showed a thermal conductivity of ∼4 W m⁻¹ K⁻¹ and the CF-TIM showed an anisotropic thermal conductivity of 41 ± 2 W m⁻¹ K⁻¹ in-plane and 20 ± 3 W m⁻¹ K⁻¹ through-plane. The thermal contact resistance of the CF-TIM was estimated to be below 1 K mm² W⁻¹. The CF-TIM showed no reduction in effective through-plane thermal conductivity after 1000 temperature cycles, which indicates the potential use of CF-TIM in thermal management applications.