Experimental Research On Packaging Adhesive Forming Based On Electrohydrodynamic Jet Printing

In recent years,with the development of microelectronic packaging technology,packaging adhesive molding technology has also developed rapidly and gradually become one of the key technologies in the field of microelectronic packaging.At present,the existing packaging adhesive molding technology is facing many challenges,such as low dispensing resolution,high process cost,high viscosity packaging adhesive is easy to block the needle and easy to produce wire drawing,etc.Aiming at how to achieve fluid dispensing with high precision and efficiency,scholars are urged to conduct more and more in-depth research in this field.Electrohydrodynamic jet printing technology is a high-resolution micro structure forming technology for additive manufacturing.The packaging adhesive forming technology based on electrohydrodynamic jet printing technology provides a new method with high resolution,high consistency,low cost and wide applicability of fluid materials for microelectronic packaging,which shows great potential application value in the field of microelectronic packaging.Based on the electrohydrodynamic jet printing technology,aiming at printing high-resolution and high consistency linear structure,this paper has carried out experimental research on thermal curing / UV curing / conductive packaging adhesive materials with different viscosities.The specific research contents are as follows:Firstly,a electrohydrodynamic jet printing platform with multi-functional modules is designed and built,which provides a high-precision experimental device for the molding research of electronic packaging adhesive;A set of software control system for electrojet printing process is developed,which provides an electrohydrodynamic jet printing control scheme integrating positioning,observation and parameter control,and meets the control requirements of packaging adhesive microstructure manufacturing with arbitrary patterns.Then,based on the electrohydrodynamic jet printing technology,an experimental study was carried out on the formation of thermal curing / UV curing / conductive packaging adhesives with different viscosities.The influence rules of key process parameters such as voltage,printing height,printing speed and supply pressure on the printing formation of different types of packaging adhesives were explored,and the high stability and high consistency of various types of packaging adhesives with different line widths are realized.Based on the above research,the thermal curing / UV curing packaging adhesive zigzag structure was printed on the surface of micro camera step bracket channel,closed-loop motor lens channel and CMOS sensor multi-layer heterostructure,and the array structure and patterned microstructure of the packaging adhesive were printed.Finally,based on the orthogonal design and range variance analysis,the printing parameters were optimized.The orthogonal tests of different factor level combinations were carried out by using the orthogonal test,and the printing results were obtained.The effects of voltage,printing height,printing speed and supply pressure on the structural dimensions of packaging adhesive were analyzed by using range analysis and variance analysis.The process parameters that have a significant impact on the test results and the optimal combination of process parameters for high-resolution microstructure printing are obtained.The combination of process parameters is verified by experiments.Within the selected range of process parameters,the minimum linewidth is about 70 μm.