Grain size and grain boundary characteristics on the out-plane thermal conductivity of <111>-oriented CVD 3C-SiC

In the integrated circuit industry, heat is transferred through the contact between wafers and the chemical vapor deposited (CVD) 3C-SiC wafer susceptor. Understanding the out-plane thermal conductivity of CVD 3C-SiC is crucial in this context. The influence of grain size and grain boundary characteristics on out-plane thermal conductivity for <111>-oriented CVD 3C-SiC was discussed in this study. The out-plane thermal conductivity sharply decreases from 146.4 W/m⸱K to 122.3 W/m⸱K when the grain size approaches 11.04 μm. This paper suggests that the significant accumulation of dislocations at high-angle grain boundaries is the primary cause of this phenomenon. The substantial lattice strain impedes phonon transfer between grain boundaries, reducing overall phonon mobility. These findings suggest that manipulating the grain boundary angle is an effective means to fine-tune heat transfer in <111>-oriented CVD 3C-SiC.