塑封成型过程芯片热流固耦合变形机理数值模拟研究

基于Castro-Macosko 固化动力学模型，建立了描述塑封填充过程及其芯片热-流-固多场耦合翘曲变形形成过程的理论模型，并揭示了其变形机理。结果表明，芯片热流固耦合翘曲变形先随熔体充填流动时间的增加而快速增加，达到最大值之后逐渐减小，并趋于恒定；芯片热-流-固耦合综合翘曲变形主要由热-流-固耦合压力场诱发的翘曲变形和不均匀温度场诱发的热变形组成，芯片热流固耦合压力场诱发的变形为向外的翘曲变形，且正比于芯片上下表面熔体充填不平衡流动的流长差和充填流动速度差，并沿轴向呈先增后减的对称抛物线分布，热-流-固耦合压力场诱发的翘曲变形远大于不均匀温度场诱发的热变形，芯片热-流-固耦合综合翘曲变形主要由热-流-固耦合压力场诱发的变形控制。

Numerical Simulation on Thermal fluid structure Coupling Deformation of Chip Plastic Encapsulation Process

In order to predict accurately chip thermal-fluid-structure coupling warpage deformation, based on the Castro-Macosko cure kinetic model, theoretical model describing plastic encapsulation filling process and thermal-fluid-structure coupling warpage deformation formatting process was established, and the formation mechanism of thermal-fluid- structure coupling warpage deformation was revealed. Research results showed that the thermal-fluid-structure coupling warpage of chip increased rapidly at first with increasing melt filling time, after reaching the maximum value decreased gradually and leveled off. The comprehensive thermal-fluid-structure coupling warpage of chips was mainly composed of the thermal-fluid-structure coupling pressure field induced warpage deformation and nonuniform temperature field induced thermal deformation, the thermal-fluid-structure coupling pressure field induced deformation was warping outward, which was proportional to the melt filling unbalance flow length difference and velocity difference of chip up and down surface, explicit first increased and then decreased symmetric parabolic distribution along the axial direction, and was far greater than the nonuniform temperature field induced thermal deformation. The comprehensive thermal-fluid-structure coupling warpage of the chips was mainly controlled by the thermal- fluid-structure coupling pressure field induced deformation.