功率器件管壳的热应力分析

Thermal Stress Analysis in Package of Power Transistor\+*

当微电子器件封装中的热应力足够大时 ,常常会导致封装开裂甚至失效 .热应力主要是在制造过程中由于环境温度变化和封装材料热失配而产生的 .因此 ,对封装设计进行热应力估算和可靠性研究是必不可少的 .采用 ABAQUS有限元计算软件 ,对某型混合集成电路的铜基金属功率外壳 ,建立了功率器件封装的三维计算模型 ,进行了应力和变形分析计算 .

Packaging failure and cracking often occur when the thermomechanical stresses in the layered electronic packaging are large enough.The stresses are formed in the manufacturing process because of the change of temperatures and the thermal mismatch between different materials.Therefore,a method to estimate the thermal stress is needed in the package design.Usually,numerical analysis is convenient and efficient to estimate the stress.A 3D model is provided by this paper to analyze the thermal stress and deformation in the package of power transistor with an ABAQUS finite element program.The calculating results provide a theoretic basis for the improvement of the reliability and the optimization of the package structure.