| In modern microelectronic industries, on the one hand, the developing trend of the microelectronic packaging technology is to make it not only be lignter, thiner, smaller and shorter in size but also be higher density, higher performance and lower cost; on the other hand, the microelectronic products have been widely applied in automobile industries, aeronautics and astronantics, telecommunication industries, etc. Their working circumstance is in badness, higher temperature and pooer heat dissipation. Thus, the reliability of the microelectronic packaging is getting more and more important, so we believe that the reliability research of the microelectronic packaging will play an important role in the future. In my paper, three main aspects were simulated and analyzed with the ANSYS software and FEA simulation. (1) The thermo-fluid coupling simulation analysis in microelectronic packaging, using MCM as research model. (2) The finite element analysis of microelectronic packaging structures under thermal cycling load, base on the theory of heat exchange, thermal elasticity mechanics and structural optimization, this paper presents the numerical simulation of the typical packaging stuctures, with emphasis on the package warpage, thermal stress and the reliability of the solder joint. (3) Base on the former analysis, thermal and thermo-mechanical characterization was developed to optimize the geometric parameters and material properties of microelectronic package.The thermo-fluid coupling simulation of a certain multichip module with liquid indirect cooling(water cold plate cooling) had been carried out using computational fluid mechanics module: ANSYS/FLOTRAN. The temperature distribution of the MCM and the flow visualization in the water cold plate were simulated and analyzed. Using APDL, I got the relationship between velocity of air and chip top temperature, and the relationship between velocity of inlet and chip top temperature. Compared with the traditional MCM using natural cooling, or heat sink cooling, it well increased the heat dissipation capability of package modules.In the microelectronic packaging, the reliability of the solder joint has been being a forward position and a hot topic. Due to the structural complications and miniaturization of the solder joint as well as device to available measuring instrumentation and experimental methods of acceptable accuracy, therefore, the direct measurement of the stress and strain of the solder joint in thermal cycle loading is not a straightforward task. Thus, the use of appropriate modeling methods and analytical tool is recommended to provide the solutions for the thermal stress and strain problems of the solder joint, which is an important way to assess the reliability of the solder joint. In this paper, based on the unified viscoplastic Anand model with the single internal variable—the deformation resistance, the viscoplastic deformation behavior of SnPb solder joint was described by use of ANSYS software and FEA simulation, the distribution of the stress and strain in compound SnPb solder joint during thermal cycling loading was derived. Through the simulation and analysis, the creep, stress relaxation of the compound SnPb solder joint, and the phenomena of temperature click pulley were observed.The optimization of the geometric parameters and material properties of multichip modules was carried out based on the former analysis by using the APDL commercial software ANSYS programming technique. Design variable was analyzed to the effect of thermo-mechanical characterizations. The results showed that the lesser elasticity module and coefficient of thermal expansion could availably reduce thermal stress, and the main factors affecting the package warpage and the solder joint reliability were the substrate thickness and the die thickness.So FEM numerical simulation technique is feasible and effectual in the electronic package design. The results are expected to act as database for improving reliability of package and optimized design. |
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