EMC材料参数对微电子封装器件热应力的影响  

Influence of EMC material parameters on thermal stress of QFN

作　　者：牛利刚[1] 杨道国[1] 李莉[1] 

机构地区：[1]桂林电子科技大学机电工程学院

出　　处：《功能材料与器件学报》2010年第4期384-388,共5页Journal of Functional Materials and Devices

基　　金：国家自然科学基金资助项目(No.60666002)

摘　　要：利用动态机械分析仪测定环氧模塑封（EMC）材料的粘弹性数据,并用广义麦克斯韦模型表征了EMC材料的粘弹松弛特性;利用热机械分析仪获得了EMC材料在不同温度时的尺寸变化量,并通过线性拟合得到了EMC材料的热膨胀系数。使用有限元软件MSC Marc分别模拟了基于EMC粘弹性、弹性两种不同性质时,QFN器件在-55~＋125℃温度条件下热应力分布,并分析了热膨胀系数对热应力的影响。结果表明：QFN器件的最大热应力出现在粘接剂、芯片和EMC材料的连接处,有限元分析中EMC的材料性质和热膨胀系数会对热应力产生较大影响。The dynamic mechanical analyzer is employed to determine the viscoelastic properties data of Epoxy Molding Compound（EMC）;And generalized Maxwell model is conducted to characterize the viscoelastic relaxation properties of EMC.The thermal mechanical analyzer is used to obtain the dimension change of EMC at different temperatures;And the thermal expansion coefficient of EMC is achieved by using linear fitting.Based on the EMC viscoelasticity and constant elasticity,finite element software MSC Marc is performed respectively to investigate the distribution of thermal stresses of QFN during temperature cycling（-55～＋125℃）.The results show that the maximum thermal stress is present to the connection of adhesive,chip and EMC.The material of EMC based on different properties and thermal expansion coefficients in finite element analysis will influence significantly on thermal stress.

关 键 词：动态机械分析 热机械分析 环氧模塑封 四方扁平无引脚封装 热应力 

分 类 号：TN304.07[电子电信—物理电子学]