| Since Gordon Moore proposed the Moore`s law in 1965,the integrated circuit density became double every 18-24 months.Chip`s packing technology is also developing rapidly.Such as the 3D packing technology is promoting the chip`s becoming smaller and more powerful.However the related heat dissipation problem is becoming the bottleneck of the technology progressing.Many solutions were proposed to solve the problems.Conventional solution such as the cooling-fin:through the heat conduction to solve the heat accumulation problem;forced air convection:fan driven air circulation to take away the heat flux;heat pipe:use the medium phase change to absorb the heat flux;thermoelectric cooling technology:use the Parr effect.Part of the cooling methods are limited,other principles are too complicated to fabricate.Since Tuckerman and Pease first proposed the micro channel heat sink,micro channel heat sink has received extensive attention and research because of its simple structure and high efficiency.In this study,a kind of micro channel heat sink was design and optimized by CFD software,fabricated by MEMS and UV-LIGA technology,and finally tested by infrared imager system.Structure part was built by GambitTM software and optimized by FluentTM.Pin height,pin fins`width and channel`s width,inlet and outlet position,pin fins`shape were all optimized by CFD software.Pin height may affect the inlet and outlet pressure drop and heat removal capacity.Under the certain coolant flow rate,when pin fin height increase the inlet and outlet pressure drop may decrease,and the heat exchange may be inadequate.While the pin fin height decrease,inlet and outlet pressure drop may increase,and heat removal efficiency may be influenced.In the study pin height range 100-1000?m were built and simulated,and 500?m was finally chosen as the best pin fins`height.Pin fins`width and channel`s width may affect the heat exchange area and cavity size.36 different designs were built and simulated in our researches,and pin fins`width 300?m,channel`s width 200?m was the best design in our simulations.63 different inlet and outlet positions were studied in the researches in order to find the best designs,and NO.22 design was finally chosen as the best.About the pin fins`shape,pin fins with cross section:triangle,square,pentagon,hexagon,circle were built and simulated,and the simulation results reveal that pin fins with hexagon cross section have the best performance.Finally some typical design were fabricated by MEMS and UG-LIGA technology and tested by infrared imager system,simulation results and experiment results showed the very similar trend.When ambient temperature is 20?,heat sink`s heat removal capacity can reach 446.39W/cm2.In this way we found the best design,and heat removal capacity was significantly improved. |
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