The Thin Plate Heat Pipe Koch Fractal Wick Structures Investigation

With the fast development of 3D packaging in the power electronics area, the vapor-liquid cooling wick structures integrated into the packages was considered an efficacious heat dissipation solution. The Koch self-similar rule was applied to design different thin vapor-liquid cooling wick structures. As a combination of the T tree and equidistant pillar array, the non-equidistant pillar array design was modeled, fabricated, and investigated. The equidistant pillar array and the non-equidistant pillar array were micro-fabricated into the silicon-glass visualization platforms for the visualization study and the IR measurements. With the smooth corners and suitable pillar pitch arrangement, the non-equidistant hexagon pillar array displayed a better heat dissipation efficiency (approximately 2.6 ± 0.2 times higher). The integrated vapor-liquid wick structure could rapidly and uniformly dissipate the local heat from the transistors into the entire substrate to guarantee the lifetime of the transistors.