Preparation And Thermodynamic Properties Of High Silicon Aluminum Alloy And Its Packaging Structure

Due to its excellent properties such as adjustable thermal expansion coefficient,easy precision machining,and plated coating,high-silicon aluminum alloys are widely used as packaging materials for semiconductor devices such as T/R(Transmitter and Receiver)components and high-power chips.However,the current preparation process of high-silicon aluminum alloys is often expensive and cumbersome,and the density of the prepared parts is insufficient.Therefore,it has become a research hotspot to explore methods for efficient preparation of high-silicon aluminum alloys.In addition,the conventional single high-silicon aluminum alloy material has low thermal conductivity,which often cannot well meet the requirements of packaging structure welding performance and thermal expansion matching,and is prone to excessive stress due to unreasonable structure.It is precisely based on the above-mentioned industry status and the development of packaging structure,this paper carries out research on a new preparation process of high silicon aluminum alloy packaging structure-pressure infiltration method,through aluminum melt refining,powder selection,mold design,process parameters setting,a high-silicon aluminum alloy was prepared.In addition,the thermal,mechanical,and mechanical properties of the prepared parts with different formulations were tested,and the design idea of fused gradient silicon and "Al/SiAl/Diamond-Al/Si" sandwich composite packaging structure was proposed.The main research contents and research results are as follows:1.Design the refining process to refine the aluminum melt,effectively control the quality and hydrogen content of the aluminum melt,and determine reasonable infiltration process parameters.Explore the filling process and powder preform forming process,provide theoretical guidance for powder preparation and filling through the measurement of the bulk volume fraction of silicon powder,and provide support for the silicon powder preform forming test through the study of binder properties.Design reasonable infiltration molding device,mold and process parameters,and finally use pressure infiltration method to prepare high-silicon aluminum alloys with various formulations.2.The thermal conductivity,thermal expansion coefficient,tensile strength,and elastic modulus of the high-silicon aluminum alloys prepared above were tested and measured,and the changing laws of thermal properties and mechanical properties with silicon particle size and volume fraction were summarized;the high-silicon aluminum alloy was tested.Alloy milling performance,summed up the changing law of milling performance with silicon particle size and volume fraction,and optimized milling parameters.3.The "Al/Si-Al/Diamond-Al/Si" sandwich composite structure was prepared by pressure infiltration method and its thermal conductivity was measured.Further design the gradient packaging structure,discuss various powder molding forms and optimize the best solution.A gradient high silicon aluminum alloy encapsulation structure embedded with Al/Diamond was manufactured,and thermal warpage deformation analysis was carried out,and the optimal shell material preparation scheme was optimized.In this paper,a new preparation process of high-silicon aluminum alloy—pressure infiltration method is studied.The thermodynamic and mechanical properties of the highsilicon aluminum alloy prepared by this process are tested,and the packaging structure selection and simulation optimization are completed,and the performance is stable.The new gradient silicon shell manufacturing parts provided practical guidance for further manufacturing.