Enhancing the thermal conductivity of epoxy molding compounds by adding SiO2-embedded carbon nanofibers for semiconductor packaging applications
摘要
This study presents the synthesis of silica-embedded carbon nanofibers (SiO2/eCNFs) as additives to enhance the heat dissipation properties of epoxy molding compounds (EMCs) for semiconductor packaging. Three different sized SiO2 nanoparticles were prepared and added to the precursor solution for polyacrylonitrile (PAN) nanofibers. Through electrospinning and carbonization, SiO2 nanoparticles-embedded PAN nanofibers were successfully converted to SiO2/eCNFs. As-fabricated SiO2/eCNFs were mixed with EMC in different concentrations from 0.1 to 1.0 wt% to investigate the effect of SiO2/eCNFs on EMC in perspective of thermal and mechanical properties. Under our experimental conditions, the addition of 500SiO2/eCNFs with 0.4 wt% EMC achieved a 67% enhancement in thermal conductivity and a 43% higher impact strength compared to pristine EMC. The improved thermal and mechanical properties by adding SiO2/eCNFs additives can be attributed to two factors: one-dimensional carbon and embedded SiO2 nanoparticles. The presence of one-dimensional carbon successfully enhanced the thermal conductivity owing to its natural graphitic characteristics and dimensional advantages. In addition, the optimal size of the SiO2 nanoparticles provided more heat dissipation routes while maintaining the packing factor compatibility with the SiO2 fillers in the EMC. In practical EMC applications for semiconductor chips, infrared (IR) camera observations confirmed a faster increase in the surface temperature with the use of SiO2/eCNFs-EMC, demonstrating the potential of these new EMC additives as next-generation high-performance semiconductors.
Graphical abstractThe improvement in the thermal conductivity of the chip molded in epoxy molding compound (EMC) through the addition of SiO2-embedded carbon nanofibers (SiO2/eCNFs) is demonstrated. The SiO2/eCNFs-EMC molded chips exhibited enhanced thermal conductivity, attributed to the formation of heat pathways through the combination of SiO2 and CNFs.