Heat Dissipation Enhancement of 2.5D Package with 3D Graphene and 3D Boron Nitride Networks as Thermal Interface Material (TIM)

Abstract

One of the major bottlenecks for the advancement in electronics is their heat dissipation. The exponential increase in packing density and computational power have resulted in a significant increase in power consumption and heat generation, such that thermal management in the new generation of microprocessor (i.e. 2.5D and 3D electronics) is starting to pose challenges in future development. These unwanted heat spots from the devices are typically extracted to the heat sink, via some thermal interface materials (TIMs). These TIMs build the important link between the heat source from the active region and the heat sink mounted on top. However, conventional TIMs are fast reaching their limits and innovative means are necessary to overcome thermal related challenges for the future generation. In this work, we present the nanostructured foam-like TIMs that are based on three-dimensional carbon (3D-C) and hexagonal boron nitride (3D-BN), with relatively high intrinsic thermal conductivities (~80 W/mK) and offer solution for both electrical conducting and insulating needs. Besides, these TIMs have ultra-high surface conformity, low weight, without the need of reflow or curing and are able to retain their high performance even at harsh environments of up to 700°C. Results on a 2.5D test chip show that these 3D foam-like TIMs have a reduction of temperature increase by 20% and of thermal resistance by 25%, significantly better than any conventional TIMs.