A SiC Based Integrated Micropillar Array Wick Thin Plate Heat Pipe Investigation

Compared with other heat dissipation systems, flat plate heat pipe (FPHP) can be manufactured in a thin plate shape, which is useful for microelectronics cooling system. Considering the SiC substrate has the same high thermal conductivity and the matched thermal expansion as the SiC-based devices, a SiC micropillar wick thin flat plate heat pipe (FPHP) architecture is proposed here for heat dissipation of SiC power devices. To compensate the requirements of bonding strength and etching uniformity, the hexagon micropillar wick architecture was fabricated inside the FPHPs. Meanwhile, the identical Si-Glass FPHPs were fabricated for comparison. The accurate and comprehensive analysis and comparison of SiC-Glass FPHP and Si-Glass FPHP were conducted utilizing the infrared (IR), Raman and high-speed camera equipment. During experiments, the maximum boiling zone of liquid inside SiC-Glass FPHP was much larger than that of Si one due to the specific heat capacity difference. The SiC-Glass FPHP CHF was close to 120 W/cm2, with a maximum 11 mm diameter boiling range. The Si-Glass one was only 55 W/cm2, with a maximum 6 mm diameter nucleate boiling range. Apparently, the SiC-Glass FPHP had a higher thermal dissipation efficiency than Si one.