Development Of Silicon-based Flat Heat Pipe With Filling Ratio And Heat Transfer Characteristics

In the development of integration on integrated circuit,high frequency,high speed and high integration make the heating power and the working temperature of the whole electronics increase rapidly,affecting the normal operation and service life of the electronic chips,which has become the important constraints of integrated circuit development.Silicon-based micro heat pipe which can match the silicon integrated circuit technology favorably and process the desired micro channels easily,has become a research hotspot in the heat pipe with high heat dissipation efficiency.In this paper,the conclusion that the heat dissipation efficiency of micro heat pipe with non-constant width micro-channels is better than the one with constant width micro-channels has been proved through the analysis of thermal and fluid simulation by ANSYS software,based on the principles of micro heat pipe heat and mass transfer.The inflection of micro-channel width and cover plate material on the MHP transfer characteristics has also been analyzed.A series of constant and non-constant micro-channels have been designed and processed on silicon wafers with the MEMS processing technology,according to the simulation results.And then the micro heat pipes can be manufactured through stickup and encapsulation.In order to research the heat transfer characteristics of the micro heat pipe by the micro-channels structure,heat source and filling ratio,the heat transfer characteristics of the micro heat pipes has been tested under the conditions of different micro-channels width,different heating power and different filling ratio,with the temperature measurement and quantitative filling fluid.The experimental results show that the heat dissipation efficiency of micro heat pipe with non-constant width micro-channels is better than the one with constant width micro-channels.The relation between cover plate material and the heat pipe transfer characteristics is quite close;silicon has been selected as the cover plate because of its higher equivalent thermal conductivity.The filling ratio impacts the heat pipe transfer characteristics obviously,the best filling ratio is 8%～12% in this paper.