Fabrication and Performance Analysis of Metallic Micro Heat Spreader for CPU

摘要

An experimental study was conducted to analyze the performance of the radial grooved metallic micro heat spreaders with 5X5X0.2 cm~3 size and a two-layer wick structure. Three types of spreader were fabricated, on the copper plate namely, etching, CNC, and sintering. The CNC- and etch-type of spreaders have a radial layout of capillary wick with the same width 2-3 mm and depth 700 μ m and 200 μ m, respectively. The sintered spreader has its capillary wick made of particle size 200-400 μ m and 0.7mm in thickness. In addition, two plates made with pure copper and composite material were also compared with these heat spreaders. Evaluation of the performance of different wick structure and various methanol filling rates were made based on the thermal resistance and conductivity at the power range of 20-80 W. The sintered heat spreader showed the best performance among all these heat spreaders, which has an effective conductivity about 800W/mK and thermal resistance of 0.23 °C/W.