Research On Topology Optimization And Integrated Colsed-Loop Control Of Micro-Displacement Positioning Stage

With the increasing development of technology, micro-electronics industry has become one of the most creative Sector of the national economy. The technology of microelectronic packages is the leader in the development of microelectronic technology and the fluid dispensing technology is the key techniques in the industrialization accomplishment of microelectronic packages. The wide application of adhesive with high performance poses new demands and challenges for the dispensing technology.On one side, with the viscosity increasing, it is easy for the adhesive to glue on the nozzle, which makes jetting difficult. On the other, the increasing packing density during the micro-electronic packaging processes has proposed a smaller diameter size requirements to the dot.Considering these problems, according to the national 863project"The Practical Research on multifunctional modularized equipment used for MEMS packaging"(granted No. 2007AA04Z343) in this paper, based on the analysis of jetting method, a non-contact jetting device aimed at dispensing adhesive with high viscosity is successfully developed to realize the steady and efficiency of high viscosity fluid's dispensing.Firstly, according to the analysis of the firing pin principle and the adhesive's flow characteristics,the key conditions is determined by building the model of the jetting process. The Fluent analysis of the fluid in nozzle is done to explore the other conditions for jetting, which provide theoretical basis for the design of the device. Based on the needs of displacement amplification, different types of amplification mechanism for micro-displacements are compared and analyzed to select the proposal in this paper.Finite element analysis (FEA) is used to analyze the structure, the dynamic performance and the harmonic responses of the amplification mechanism designed. The size parameters of the spring is then designed and validated. the founded dynamic equation including piezostack, needle and amplification mechanism is solved by MATLAB to get the displacement and velocity diagram of the needle.According to the driving demands of the device, the driving system is designed. The performance of the piezoelectric and the amplification mechanism are tested and the result is basically compatible with that of the simulation, which indicates that the driving system can satisfy the needs of the device.Finally, experimental system is built and the performance test of the jetting device is carried out based on the above analysis results.The effect of working coefficient including the voltage amplitude, frequency, viscosity diameter of the nozzle and supplying pressure on the output flow is studied by experiment. The accuracy and repeatability of the dispensing for Micro droplets is also tested. The experimental results indicate that the jetting device can dispense the adhesive required steadily, achieving the desired effect.