Study of the effect of Si/Dia interface structure on heat dissipation

With the increasing power density and reduced size of the chip, the heat dissipation in the chip has become a critical issue in real applications. Diamond, with the highest thermal conductivity among all the natural materials, is interested in integrating with high-power chips to dissipate heat. However, reducing the thermal interface resistance (TIR) between diamond and chip is a big challenge. This work proposes the direct integration of Si and diamond using Ti/Cu/Ti/Au multilayer metals. The TIR of the bonding interfaces has been investigated by time-domain thermoreflectance(TDTR). The TIR of Si/Ti, Ti/Cu, and Ti/Au interfaces is 7.7E-7 K/Wm2, 2.1E-7 K/Wm2 and 2.0E-7 K/Wm2, respectively. In addition, the temperature distribution of Chip/Au-Ti-Cu-Ti-Au/Dia and Chip/Au-Ti-Au/Dia has been studied by Finite Element Analysis (FEA). The results show that both chip structures have a surface temperature of 76℃ at 2.1 W/mm. These results will provide theoretical support for the heat dissipation design of high-power density devices and good evidence for Ti/Cu/Ti/Au structures.