Study On Preparation And Properties Of Electronic Packaging Materials In High Aluminum-Silicon Alloy

With the development of social economy,great progress has been made in modern VLSI.While the advanced integrated circuit technology is developing rapidly,the development of modern electronic packaging technology is lagging behind to a certain extent.For the technical requirements of modern electronic packaging materials,electronic packaging materials,as a matrix material,play the role of bearing electronic components and mutual connection,environmental protection,mechanical support,heat loss of electronic components and other functions,and at the same time,it is required to have a good insulation ability.As an important part of integrated circuits,electronic packaging materials need to meet the basic requirements of matching thermal expansion property,high thermal conductivity,as well as material density and strength requirements.This paper mainly explores the Al-60 wt.%Si system as the research object,using powder metallurgy liquid phase sintering method to prepare low expansion,low density,high thermal conductivity Al-Si electronic packaging specific process path.The effect of ball milling time on powder size and the change of microstructure and properties of high silicon aluminum alloy electronic packaging materials with ball milling time were studied.Determine the best ball milling time in the process of ball milling.The results showed that the particle size of the composite powder before and after ball milling decreased obviously when the ball milling time was 6h.The uniformity of the composite powder was the best,and the particle size of the composite powder was also guaranteed.The average particle size of the composite powder was 5.232?m.The Al matrix is distributed in a continuous network,while the silicon phase is in a skeleton structure with few internal pores,so the dense and uniform microstructure can be obtained.The density is2.457g/cm³,the maximum thermal conductivity is 120.4W/m·K,the average thermal expansion coefficient is 10.46×10^-6K^-1 at room temperature to 100 ?,and the hardness value is 136 HBW.It can meet the requirements of electronic packaging materials.The effect of powder preheating temperature on the properties of high silicon aluminum alloy electronic packaging materials was studied.Results show that in the process of pressing sintering,powder preheating temperature is 400?,mould preheating temperature is 350 ?,the vacuum sintering temperature at 850 ?,the sintering time when 2h,materials organized pore,at least reach maximum thermal conductivity is124.88W/m K,under the condition of room temperature to 100?,the average thermal expansion coefficient of 11.95×10^-6K^-1,optimum thermal physical properties,the material has the highest density can reach 2.469g/cm³,relative density of 99.96%,and the hardness value of 118 HBW.The effect of carbon nanotube content on the microstructure and properties of high silicon aluminum alloy electronic packaging materials was studied.The results show that for high silicon aluminum alloy electronic packaging materials,adding a certain amount of CNTs can effectively reduce the thermal expansion coefficient of the material.When the content of CNTs is 1.2%,the powder uniformity is the best,and the compact and uniform microstructure can be obtained.The density of the material is 2.441g/cm³,the maximum thermal conductivity is 113.41W/m·K,the low thermal expansion coefficient is 9.79×10^-6K^-1,and the hardness value is 200.5HBW,which is 34.01% higher than that of the material without addition.