粘接剂对直接粘贴芯片表面残余应力的影响

Effect of different adhesives on the evolution of residual stress at chip surface during and after curing for COB packages

封装所导致的残余应力是电子器件封装和组装重点关注的问题。利用硅压阻传感器,原位实时地记录了不同粘接剂在FR4有机层压板衬底上固化过程中芯片表面的应力变化和残余应力的分布状况。研究表明,使用热膨胀系数较小的有机粘接剂粘贴芯片时,可获得较低的残余应力和相对优越的应力分布。该方法可作为芯片直接粘接时选择有机粘接剂的参照。

The residual stress induced by pack aging has been an important problem i n the electronic packaging and assembly.Silicon pie zoresistive sensor is applied here t o in -situ record the curing stress evolution for different adhesives and the distributions of the re sidual stress.Results indicate that lower residual stress will be ob tained when an organic adhesive with lower thermal expansion co -efficient is employed to bond the chi p.This method can be used as a referen ce to select an ideal ad -hesive for COB(Chip on Board)packages.