The Process And Cooling Performance Test Analysis For TSV Interposer Integrated With Microchannel

With the advent of the information age,the 2.5D/3D integration has made great progress in variety of emerging applications.Good cooling performance is critical under increasing demands for high performance,high integration and miniaturization.The microchannel is an active cooling technology which has low thermal resistance,large heat transfer coefficient and good heat dissipation.On the one hand,the previous research works have proved the feasibility and advancement of the microchannel cooling technology for high power devices,and some technologies have gradually entered the research stage of engineering application.On the other hand,it can be found that the 3D package integrated with the microchannel cooling technology are slowly development,it still faces enormous challenges such as compatible manufacturing and multi-physics coupling effects,and it is still a long way from engineering application.Meanwhiles,The cooling issues become more challenging when the heterogeneous integration is rapidly developmented,such as GaN RF chips.This paper proposes a TSV interposer embedded microchannel for 2.5D/3D GaN RF devices,which mainly carries out a series of research work focusing on the structural design,manufacture process,performance testing,integrated package and limit exploration for TSV interposer integrated with microchannel.In this paper,four kinds of microchannel structures and coaxial TSV vertical interconnect structure are designed respectively,which meet the requirements of microchannel heat dissipation and TSV electrical transmission,and provide an effective design scheme for 2.5D/3D integrated applications.The fabrication process compatibled with the TSV manufacture process is developed.The TSV interposer embedded microchannel was successfully fabricated by flexible adjustment of Si-Si direct bonding,thinning process,double-sided conformal plating and other manufacturing technologies,which verified the feasibility of the process manufacturing and formed an optimized process scheme.The microchannel thermal characteristics are studied by integrating Pt resistors and 2.5D integrated analog power chips on microchannel interposer sample.The test system of microchannel cooling performance is established.We carried out the test analysis of the heat dissipation characteristics for different TSV interposer integrated microchannels.According to the above process research and thermal characteristics test for TSV interposer with microchannel,this paper proposes a heterogeneous integrated packaging technology based on the TSV interposer embedded with microchannel.The 2.5D integration design,package and test of 2-6GHz GaN RF power amplifier module intergrated TSV interposer with microchannel is carried out.The test shows that the high-power GaN RF power amplifier module can work normally under the action of microchannel cooling,the flow rate of coolant is 80mL/min and the equivalent heat flux is about 425W/cm2,which verifies the feasibility of the technology scheme.The heat dissipation characteristic analysis models of the TSV interposer embedded microchannel are established.Compared with the above experimental datas,the deviation of the simulation model is analyzed.The limit of heat dissipation capability for different microchannel structure is predicted and analyzed,which provides guidance and suggestions for the subsequent application design and development.